Citizen Scientists Reveal a Bubbly Milky Way
The findings make scientists suspect that the Milky Way is a much more active star-forming galaxy than previously thought.
March 9, 2012
team of volunteers from the general public has pored over observations
from NASA's Spitzer Space Telescope and discovered more than 5,000
"bubbles" in the disk of our Milky Way Galaxy. Credit: NASA/JPL-Caltech/Oxford University
team of volunteers has pored over observations from NASA’s Spitzer
Space Telescope and discovered more than 5,000 “bubbles” in the disk of
our Milky Way Galaxy. Hot, young stars blow these bubbles into
surrounding gas and dust, indicating areas of new star formation.
of 35,000 “citizen scientists” sifted through the Spitzer infrared data
as part of the online Milky Way Project to find these telltale bubbles.
The volunteers have turned up 10 times as many bubbles as previous
surveys so far.
“These findings make us suspect that the Milky
Way is a much more active star-forming galaxy than previously thought,”
said Eli Bressert from the European Southern Observatory, Germany, and
the University of Exeter, England. “The Milky Way’s disk is like
champagne with bubbles all over the place,” he said.
programs struggle at identifying the cosmic bubbles, but human eyes and
minds do an excellent job of noticing the wispy arcs of partially broken
rings and the circles-within-circles of overlapping bubbles. The Milky
Way Project taps into the “wisdom of crowds” by requiring that at least
five users flag a potential bubble before its inclusion in the new
catalog. Volunteers mark any candidate bubbles in the infrared Spitzer
images with a sophisticated drawing tool before proceeding to scour
“The Milky Way Project is an attempt to take the
vast and beautiful data from Spitzer and make extracting the information
a fun, online, public endeavor,” said Robert Simpson from Oxford
The data come from the Spitzer Galactic
Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) and Multiband
Imaging Photometer for Spitzer Galactic (MIPSGAL) surveys. These
datasets cover a narrow, wide strip of the sky measuring 130° wide and
just 2° tall. From a stargazer’s perspective, a 2° strip is about the
width of your index finger held at arm’s length, and your arms opened to
the sky span about 130°. The surveys peer through the Milky Way’s disk
and right into our galaxy’s heart.
The bubbles tagged by the
volunteers vary in size and shape, both with distance and due to local
gas cloud variations. The results will help astronomers better identify
star formation across the galaxy. One topic under investigation is
triggered star formation in which the bubble-blowing birth of massive
stars compresses nearby gas that then collapses to create further fresh
“The Milky Way Project has shown that nearly a third of
the bubbles are part of hierarchies where smaller bubbles are found on
or near the rims of larger bubbles,” said Matthew Povich from Penn
State, University Park. “This suggests new generations of star formation
are being spawned by the expanding bubbles.”
Variations in the
distribution pattern of the bubbles intriguingly hint at structure in
the Milky Way. For example, a rise in the number of bubbles around a gap
at one end of the survey could correlate with a spiral arm. Perhaps the
biggest surprise is a drop-off in the bubble census on either side of
the galactic center. “We would expect star formation to be peaking in
the galactic center because that’s where most of the dense gas is,” said
Bressert. “This project is bringing us way more questions than
In addition, the Milky Way Project users have
pinpointed many other phenomena, such as star clusters and dark nebulae,
as well as gaseous “green knots” and “fuzzy red objects.” Meanwhile,
the work with the bubbles continues, with each drawing helping to refine
and improve the catalog.
For those interested in counting bubbles and contributing to the Milky Way Project, visit its website
To learn of other citizen science-based efforts, check out the Zooniverse
NASA’s Chandra Finds Largest Galaxy Cluster in Early Universe
exceptional galaxy cluster, the largest seen in the distant universe,
has been found using NASA’s Chandra X-ray Observatory and the National
Science Foundation-funded Atacama Cosmology Telescope (ACT) in Chile.
known as ACT-CL J0102-4915, the galaxy cluster has been nicknamed “El
Gordo” (“the big one” or “the fat one” in Spanish) by the researchers
who discovered it. The name, in a nod to the Chilean connection,
describes just one of the remarkable qualities of the cluster, which is
located more than 7 billion light years from Earth. This large distance
means it is being observed at a young age.
“This cluster is the
most massive, the hottest, and gives off the most X-rays of any known
cluster at this distance or beyond,” said Felipe Menanteau of Rutgers
University in New Brunswick, N.J., who led the study.
clusters, the largest objects in the universe that are held together by
gravity, form through the merger of smaller groups or sub-clusters of
galaxies. Because the formation process depends on the amount of dark
matter and dark energy in the universe, clusters can be used to study
these mysterious phenomena.
Dark matter is material that can be
inferred to exist through its gravitational effects, but does not emit
and absorb detectable amounts of light. Dark energy is a hypothetical
form of energy that permeates all space and exerts a negative pressure
that causes the universe to expand at an ever-increasing rate.
galaxy clusters like this are just what we were aiming to find,” said
team member Jack Hughes, also of Rutgers. “We want to see if we can
understand how these extreme objects form using the best models of
cosmology that are currently available.”
Although a cluster of El
Gordo’s size and distance is extremely rare, it is likely that its
formation can be understood in terms of the standard Big Bang model of
cosmology. In this model, the universe is composed predominantly of dark
matter and dark energy, and began with a Big Bang about 13.7 billion
The team of scientists found El Gordo using ACT thanks
to the Sunyaev-Zeldovich effect. In this phenomenon, photons in the
cosmic microwave background interact with electrons in the hot gas that
pervades these enormous galaxy clusters. The photons acquire energy from
this interaction, which distorts the signal from the microwave
background in the direction of the clusters. The magnitude of this
distortion depends on the density and temperature of the hot electrons
and the physical size of the cluster.
X-ray data from Chandra and
the European Southern Observatory’s Very Large Telescope, an 8-meter
optical observatory in Chile, show El Gordo is, in fact, the site of two
galaxy clusters colliding at several million miles per hour. This and
other characteristics make El Gordo akin to the well-known object called
the Bullet Cluster, which is located almost 4 billion light years
closer to Earth.
As with the Bullet Cluster, there is evidence
that normal matter, mainly composed of hot, X-ray bright gas, has been
wrenched apart from the dark matter in El Gordo. The hot gas in each
cluster was slowed down by the collision, but the dark matter was not.
is the first time we’ve found a system like the Bullet Cluster at such a
large distance,” said Cristobal Sifon of Pontificia Universidad de
Catolica de Chile (PUC) in Santiago. “It’s like the expression says: if
you want to understand where you’re going, you have to know where you’ve
These results on El Gordo are being announced at the 219th
meeting of the American Astronomical Society in Austin, Texas. A paper
describing these results has been accepted for publication in The
NASA’s Marshall Space Flight Center in
Huntsville, Ala., manages the Chandra program for NASA’s Science Mission
Directorate in Washington. The Smithsonian Astrophysical Observatory
controls Chandra’s science and flight operations from Cambridge, Mass.
New Evidence for Liquid Water on Europa
Nov. 16, 2011: In a potentially significant
finding in the search for life beyond Earth, scientists studying data
from NASA's Galileo probe have discovered what appears to be a body of
liquid water the volume of the North American Great Lakes locked inside
the icy shell of Jupiter’s moon Europa.
The water could represent a potential habitat for life, and many
more such lakes might exist throughout the shallow regions of Europa’s
shell, say researchers writing in the journal Nature.
"The data opens up some compelling possibilities," said Mary
Voytek, director of NASA's Astrobiology Program at agency headquarters
in Washington. "However, scientists worldwide will want to take a close
look at this analysis and review the data before we can fully appreciate
the implication of these results."
A new study of data from the Galileo probe suggest
Grate-Lake-sized bodies of water exist in the icy shell of Europa.
Credit: Britney Schmidt/Dead Pixel FX/Univ. of Texas at Austin [video
The Galileo spacecraft, launched by the space shuttle Atlantis in
1989, provided scientists decades of data to analyze before the probe
plunged into Jupiter's atmosphere in 2003. One of the most significant
discoveries was the inference of a global salt water ocean below the
surface of Europa. This ocean is deep enough to cover the whole surface
of Europa and contains more liquid water than all of Earth's oceans
combined. However, being far from the sun, the ocean surface is
completely frozen. Most scientists think this ice crust is tens of miles
"One opinion in the scientific community has been if the ice shell
is thick, that's bad for biology. That might mean the surface isn't
communicating with the underlying ocean," said Britney Schmidt, lead
author of the Nature paper and postdoctoral fellow at the
Institute for Geophysics, University of Texas at Austin. "Now, we see
evidence that it's a thick ice shell that can mix vigorously and new
evidence for giant shallow lakes. That could make Europa and its ocean
Thera Macula (false color) is a region of likely active chaos
production above a large liquid water lake in the icy shell of Europa. [larger image
Schmidt and her team focused on Galileo images of two roughly
circular, bumpy features on Europa's surface called chaos terrains.
Based on similar processes seen on Earth -- on ice shelves and under
glaciers overlaying volcanoes -- they developed a four-step model to
explain how the features form. The model resolves several conflicting
observations. Some seemed to suggest the ice shell is thick. Others
suggest it is thin.
The recent analysis suggests chaos features on Europa's surface
are formed by mechanisms that involve significant exchange between the
icy shell and the underlying lake. This kind of "chaos" may provide a
pathway for transferring nutrients and energy between the surface and
the vast global ocean already thought to exist below the thick ice
shell. Researchers believe this would increase the potential for life
"This new understanding of processes on Europa would not have been
possible without the foundation of the last 20 years of observations
over Earth's ice sheets and floating ice shelves,” said Don Blankenship,
a co-author and senior research scientist at the Institute for
Geophysics, where he leads airborne radar studies of Earth’s ice sheets.
The authors have good reason to believe their model is correct.
Still, because the inferred lakes are several miles below the surface,
the only true confirmation of their presence would come from a future
spacecraft mission designed to probe the ice shell. Such a mission was
rated as the second highest priority flagship mission by the National
Research Council's recent Planetary Science Decadal Survey and is being
studied by NASA.
For more images and a video animation of the findings, visit the University of Texas at Austin. .
Production Editor: Dr. Tony Phillips | Credit: Science@NASA
Galileo was the first spacecraft to directly measure
Jupiter's atmosphere with a probe and conduct long-term observations of
the Jovian system. The probe was the first to fly by an asteroid and
discover the moon of an asteroid. NASA extended the mission three times
to take advantage of Galileo's unique science capabilities, and it was
put on a collision course into Jupiter's atmosphere in September 2003 to
eliminate any chance of impacting Europa.
The Galileo mission was managed by NASA's Jet Propulsion
Laboratory in Pasadena, Calif., for the agency's Science Mission
Another Antimatter Supernova Discovered
by Nicholos Wethington on January 7, 2010
Here’s another extremely explosive supernova that can be chalked up to the production of antimatter in the core of the star:
Y-155. These types of supernova explosions – which can be ten times
brighter than the already spectacular explosion of a Type Ia supernova –
have been theorized to exist for over forty years. About a month ago,
we reported on the first observations of one of
these types of supernovae, and at the American Astronomical Society
super-meeting yesterday, Peter Garnavich of the University of Notre Dame
presented on the observation of a second.
The star Y-155 was a whopping large star, with a mass of over 200 times that of our Sun. In these types of stars, energetic gamma
rays can be created by the intense heat in the core of the star. These
gamma rays in turn make pairs of electrons and positrons, or antimatter
pairs. Since so much energy goes to the creation of these pairs, the
pressure pushing outwards on the star weakens, and gravity swoops in to
collapse the star, generating a supernova of enormous proportions.
These types of supernovae have been dubbed “pair-instability”
supernovae, and once they explode, there is nothing left: in other types
of supernovae, a neutron star or black hole can form out of the
remnants of the star, but pair-instability supernovae explode with such
force that there is nothing left where the core of the star once
In addition to Supernova 2007bi, which we reported on in Dec of 2009, the Supernova 2006gy is another candidate for this supernova type.
Y-155, which lies in the constellation Cetus, was discovered as part
of the Equation of State: SupErNovae trace Cosmic Expansion,”ESSENCE”,
search for stellar explosions. During the 6-year search, a team of
international astronomers led Christopher Stubbs of Harvard University
collaborated to find Type Ia supernovae as a means to measure the
expansion of the Universe. These types of supernovae explode with a
characteristic luminosity, making them excellent candidates to measure
distances in the Universe. The team utilized the National Optical
Astronomy Observatory’s (NOAO) 4-m Blanco telescope in Chile.
Y-155 was discovered in November of 2007, during the last weeks of
the project, using the Blanco telescope. Once the initial discovery was
made, followup observations using the Keck 10-m telescope in Hawaii, the
Magellan telescope in Chile, and the MMT telescope in Arizona revealed
the redshifting of the light due to the expansion of the Universe to be
about 80%, meaning that the star is very far away, and thus very old.
Y-155 is estimated to have undergone a supernova approximately 7 billion
According to Garnavich, the team calculated the star to be generating 100 billion times the energy of the Sun
at its peak. To accomplish this, it must have synthesized between 6 and
8 solar masses of nickel 56, which is what gives Type Ia supernovae
their brightness. For comparison, the typical Type Ia supernova burns
0.4-0.9 solar masses of nickel 56.
Y-155 has been shown by deep imaging with the Large Binocular
Telescope in Arizona to reside in a galaxy that is rather small. Smaller
galaxies are usually low in heavier atoms. The gas out of which this
and other types of ultra-massive stars form is relatively pristine,
composed largely of hydrogen and helium. Supernova 2007bi, the
first-observed pair-instability supernova, grew up in a galaxy
remarkably like that of Y155.
This means that when astronomers look for other types of
pair-instability supernovae, they should find more of them in smaller
galaxies that existed near the beginning of the Universe, before other
supernovae synthesized heavier elements and spread them around.
Another Asteroid To Give Earth a Close Shave June 27, 2011
by Nancy Atkinson on June 23, 2011 from UniverseToday.com
2011 MD's orbital parameters. Credit: JPL Small-Body Database Browser
A newly discovered house-sized asteroid will miss the Earth by less than
17,700 km (11,000 miles) on Monday June 27, 2011. That’s about 23
times closer than the Moon. The size and location of the asteroid,
named 2011 MD, should allow observers in certain locations to take a
look at the space rock, even with small telescopes.
approach will be at 13:26 UTC (9:26 AM EDT) on June 27.
According to Skymania,
2011 MD was found just yesterday, June 22, by LINEAR, a pair of robotic
telescopes in New Mexico that scan the skies for Near Earth Asteroids.
As of now, asteroid 2011 MD is estimated to be between 9 to 45 meters (10 to 50 yards) wide. Dr. Emily Baldwin, of Astronomy Now magazine,
said there is no danger of the asteroid hitting Earth, and even if it
did enter the atmosphere, an asteroid this size would “mostly burn up in
a brilliant fireball, possibly scattering a few meteorites.”
To find out updated information on 2011 MD’s ephemeris, physical
parameters and more, including an orbit diagram and close-approach data,
see this page on JPL’s Solar System Dynamics website.
NASA UPDATE FROM SPACE.COM
A small asteroid the size of a tour bus will make an extremely close
pass by the Earth at about that time, but it poses no threat to the
The asteroid will make its closest approach at 9:26 a.m. EDT (1326 GMT)
on June 27 and will pass just over 7,500 miles (12,000 kilometers)
above the Earth's surface, NASA officials say. At that particular
moment, the asteroid — which scientists have named 2011 MD — will be
sailing high off the coast of Antarctica, almost 2,000 miles (3,218 km)
south-southwest of South Africa.
NOTE THAT THE 11,000 MILE FIGURE GIVEN ABOVE IS THE DISTANCE TO THE EARTH'S CENTER.
THE 7500 MILES FIGURE ABOVE IS AN ALTITUDE DISTANCE ABOVE THE CLOSEST POINT ON THE EARTH'S SURFACE.
Asteroid 2011 MD was discovered Wednesday (June 22) by LINEAR, a pair of robotic telescopes in New Mexico that scan the skies for near-Earth asteroids. The best estimates suggest that this asteroid is between 29 to 98 feet (9 to 30 meters) wide.
THE ASTRONOMY PICTURE OF THE DAY FOR 2011 June 14
The Universe Nearby
T. H. Jarrett, J. Carpenter, & R. Hurt
What does the universe nearby look like?
This plot shows nearly 50,000 galaxies in the nearby universe detected by the
Two Micron All Sky Survey infrared
The resulting image is anincredible tapestry of galaxies that
provides limits on how the universe formed and evolved.
The dark band across
the image center is blocked by dust in the
plane of our own
Milky Way Galaxy.
Away from the Galactic plane, however, each dot represents a
coded to indicate distance.
Bluer dots represent the nearer galaxies in the
while redder dots indicating the more
distant survey galaxies that lie at a
redshift near 0.1 .
Named structures are annotated around the edges.
Many galaxies are
gravitationally bound together to form
which themselves are loosely bound into
which in turn are sometimes seen to
align over even larger scale structures.
THE ASTRONOMY PICTURE OF THE DAY FOR 2011 June 5
Another Nearby Supernova in the Whirlpool Galaxy Discovered 2011 May 31st
Credit & Copyright:
Stephane Lamotte Bailey,
Marc Deldem, &
One of the brightest supernovas in recent years has just been recorded in the nearby Whirlpool galaxy (M51).
Surprisingly, a seemingly
similar supernova was recorded in M51 during 2005, following yet another one that occurred in 1994.
Three supernovas in 17 years is a lot for single galaxy, and reasons for the
supernova surge in M51 are being debated.
Pictured above are two images of
M51 taken with a small telescope: one taken on May 30 that does not show the supernova, and one taken on June 2 which does.
The June 2 image is one of the first images reported to contain the supernova.
The images are blinked to show the location of the
Although most supernovas follow
classic brightness patterns, the precise brightening and dimming pattern of this or any supernova is hard to predict in advance and can tell astronomers much about what is happening.
M51 supernova, designated
SN 2011dh, is still bright enough to follow with a small telescope.
Therefore, sky enthusiasts are encouraged to image the
as often as possible to fill in time gaps left by intermittent observations made by the world's most powerful telescopes.
Views of the developing supernova are being
THE ASTRONOMY PICTURE OF THE DAY FOR 2011 June 11
Supernovae in the Whirlpool
Image Credit &
R Jay Gabany
Where do spiral galaxies keep their supernovae?
Near their massive star forming regions,
and those regions tend to lie along sweeping blue spiral arms.
Because massive stars
are very short-lived, they don't
have a chance to wander far from their birth place.
Remarkably, in the last 6 years two
the death explosions of massive stars, have been detected in
nearby spiral M51.
Along with a third supernova seen in 1994,
that amounts to a supernova bonanza
for a single galaxy.
As demonstrated in these
comparison images, SN2005cs, the supernova discovered in 2005,
and more recently SN2011dh,
the exceptionally bright supernova first recorded just last month,
both lie along M51's grand spiral arms.
Perhaps the original spiral nebula, M51
is also known as the Whirlpool Galaxy.
THE ASTRONOMY PICTURE OF THE DAY FOR 2011 MAY 23
An Unexpected Flare from the Crab Nebula
LAT, R. Buehler
Why does the Crab Nebula flare?
No one is sure.
The unusual behavior,
over the past few years, seems only to
very high energy light --
As recently as one month ago, gamma-ray observations of the
Crab Nebula by the
Fermi Gamma Ray Space Telescope showed an
unexpected increase in gamma-ray brightness, becoming about five times the nebula's usual gamma-ray brightness, and
fading again in only a few days.
Now usually the faster the variability, the smaller the region involved.
This might indicate that the powerful pulsar at the
center of the Crab,
a compact neutron star rotating 30 times a second, is somehow involved.
speculation is centered on the changing
that surely surrounds the powerful
Rapid changes in this field might lead to waves of rapidly accelerated electrons which emit
ways similar to our
The above image shows how the Crab Nebula normally
appears in gamma rays, as compared to the
Geminga pulsar, and how it then appeared during the recent brightening.
MISSING SUNSPOTS IN 2008-9 EXPLAINED IN THE 2011 MARCH ISSUE OF NATURE
THE VIDEO BELOW SUMMARIZES THE ARTICLE
Discovery Triples Number of Stars in Universe
Published: December 1, 2010
Astronomers detected the
faint signature of small, dim red dwarf stars in nearby galaxies
(right), and found they are much more numerous than in our own Milky Way
(left). (Illustration: Patrick Lynch/Yale University)
New Haven, Conn. — Astronomers have discovered that
small, dim stars known as red dwarfs are much more prolific than
previously thought—so much so that the total number of stars in the
universe is likely three times bigger than realized.
Because red dwarfs are relatively small and dim compared to stars
like our Sun, astronomers hadn’t been able to detect them in galaxies
other than our own Milky Way and its nearest neighbors before now. As
such, they did not know how much of the total stellar population of the
universe is made up of red dwarfs.
Now astronomers have used powerful instruments on the Keck Observatory in Hawaii to
detect the faint signature of red dwarfs in eight massive, relatively
nearby galaxies called elliptical galaxies, which are located between
about 50 million and 300 million light years away. They discovered that
the red dwarfs, which are only between 10 and 20 percent as massive as
the Sun, were much more bountiful than expected.
“No one knew how many of these stars there were,” said Pieter van
Dokkum, a Yale University astronomer who led the research, which is
described in Nature’s Dec.1 Advanced Online Publication. “Different
theoretical models predicted a wide range of possibilities, so this
answers a longstanding question about just how abundant these stars
The team discovered that there are about 20 times more red dwarfs in
elliptical galaxies than in the Milky Way, said Charlie Conroy
of the Harvard-Smithsonian Center
for Astrophysics, who was also involved in the research.
“We usually assume other galaxies look like our own. But this
suggests other conditions are possible in other galaxies,” Conroy said.
“So this discovery could have a major impact on our understanding of
galaxy formation and evolution.”
For instance, Conroy said, galaxies might contain less dark matter—a
mysterious substance that has mass but cannot be directly observed—than
previous measurements of their masses might have indicated. Instead, the
abundant red dwarfs could contribute more mass than realized.
In addition to boosting the total number of stars in the universe,
the discovery also increases the number of planets orbiting those stars,
which in turn elevates the number of planets that might harbor life,
van Dokkum said. In fact, a recently discovered exoplanet that
astronomers believe could potentially support life orbits a red dwarf
star, called Gliese
“There are possibly trillions of Earths orbiting these stars,” van
Dokkum said, adding that the red dwarfs they discovered, which are
typically more than 10 billion years old, have been around long enough
for complex life to evolve. “It’s one reason why people are interested
in this type of star.”
Citation: DOI: 10.1038/nature09578
PRESS CONTACT: Suzanne
Taylor Muzzin 203-432-8555
Discovery of "Arsenic-bug" Expands Definition of Life
Dec. 2, 2010:
NASA-supported researchers have discovered the first known
microorganism on Earth able to thrive and reproduce using the toxic
chemical arsenic. The microorganism, which lives in California's Mono
Lake, substitutes arsenic for phosphorus in the backbone of its DNA and
other cellular components.
A microscopic image of GFAJ-1 grown on arsenic. [larger
"The definition of life has just expanded," said Ed Weiler, NASA's
associate administrator for the Science Mission Directorate at the
agency's Headquarters in Washington. "As we pursue our efforts to seek
signs of life in the solar system, we have to think more broadly, more
diversely and consider life as we do not know it."
This finding of an alternative biochemistry makeup will alter
biology textbooks and expand the scope of the search for life beyond
Earth. The research is published in this week's edition of Science
Carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur are the
six basic building blocks of all known forms of life on Earth.
Phosphorus is part of the chemical backbone of DNA and RNA, the
structures that carry genetic instructions for life, and is considered
an essential element for all living cells.
Phosphorus is a central component of the energy-carrying molecule
in all cells (adenosine triphosphate) and also the phospholipids that
form all cell membranes. Arsenic, which is chemically similar to
phosphorus, is poisonous for most life on Earth. Arsenic disrupts
metabolic pathways because chemically it behaves similarly to phosphate.
"We know that some microbes can breathe arsenic, but what we've
found is a microbe doing something new -- building parts of itself out
of arsenic," said Felisa Wolfe-Simon, a NASA Astrobiology Research
Fellow in residence at the U.S. Geological Survey in Menlo Park, Calif.,
and the research team's lead scientist. "If something here on Earth can
do something so unexpected, what else can life do that we haven't seen
The newly discovered microbe, strain GFAJ-1, is a member of a
common group of bacteria, the Gammaproteobacteria. In the laboratory,
the researchers successfully grew microbes from the lake on a diet that
was very lean on phosphorus, but included generous helpings of arsenic.
When researchers removed the phosphorus and replaced it with arsenic the
microbes continued to grow. Subsequent analyses indicated that the
arsenic was being used to produce the building blocks of new GFAJ-1
The key issue the researchers investigated was when the microbe
was grown on arsenic did the arsenic actually became incorporated into
the organisms' vital biochemical machinery, such as DNA, proteins and
the cell membranes. A variety of sophisticated laboratory techniques was
used to determine where the arsenic was incorporated.
The team chose to explore Mono Lake because of its unusual
chemistry, especially its high salinity, high alkalinity, and high
levels of arsenic. This chemistry is in part a result of Mono Lake's
isolation from its sources of fresh water for 50 years.
Geomicrobiologist Felisa Wolfe-Simon, collecting lake-bottom
sediments in the shallow waters of Mono Lake in California. Credit:
©2010 Henry Bortman [more
The results of this study will inform ongoing research in many
areas, including the study of Earth's evolution, organic chemistry,
biogeochemical cycles, disease mitigation and Earth system research.
These findings also will open up new frontiers in microbiology and other
areas of research.
"The idea of alternative biochemistries for life is common in
science fiction," said Carl Pilcher, director of the NASA Astrobiology
Institute at the agency's Ames Research Center in Moffett Field, Calif.
"Until now a life form using arsenic as a building block was only
theoretical, but now we know such life exists in Mono Lake."
The research team included scientists from the U.S. Geological
Survey, Arizona State University in Tempe, Ariz., Lawrence Livermore
National Laboratory in Livermore, Calif., Duquesne University in
Pittsburgh, Penn., and the Stanford Synchroton Radiation Lightsource in
Menlo Park, Calif.
NASA's Astrobiology Program in Washington contributed funding for
the research through its Exobiology and Evolutionary Biology program and
the NASA Astrobiology Institute. NASA's Astrobiology Program supports
research into the origin, evolution, distribution, and future of life on
Tony Phillips | Credit: Science@NASA
Published online 20 October 2010 |
Most Distant Galaxy Ever Found Sheds Light on Infant Cosmos
Object allows astronomers a glimpse of
Universe's era of 'reionization'.
Light from a
distant galaxy has provided a snapshot of the early universe.ESO/L. Calçada
the most distant object yet discovered go a long way in supporting
astronomers' models of the early Universe. But the far-flung galaxy,
details of which are published in Nature 2010 Oct 201,
also raises questions about the source of the first light in the
Light from the galaxy, named UDFy-38135539, left the object just 600
million years after the Big Bang, giving a snapshot of the cosmos in
its infancy. This value smashes the previous record held by a galaxy by
150 million years2.
The image shows the galaxy as it was when it was around 100 million
years old and is just 1-10% of the mass of the Milky Way.
The galaxy is particularly fascinating because, 600 million years
after the Big Bang, the Universe was thought to be going through a phase
called reionization. However, there has been little direct
observational evidence for this, says astronomer Matt Lehnert at the
Paris Observatory in France, who led the team involved in the study.
According to astronomers' best models, the early Universe burst out of
the Big Bang around 13 billion years ago as an ionized fireball. This
ball of gas gradually cooled, becoming neutral as protons and neutrons
combined to form hydrogen. "Then stars and galaxies began to form,
lighting up the Universe, heating up the gas and reionizing it," says
Lehnert. "This galaxy allows us to peek at the reionization era."
At the Limit
The first hint of the
galaxy's existence came when astronomers scrutinized a near-infrared
image taken by the Hubble Space Telescope's Wide Field Camera and saw "a
faint blob", says Lehnert3.
To confirm its distance, Lehnert and his colleagues searched for a
characteristic signature, called the Lyman-α line, that is seen in the
spectrum of light emitted by galaxies. The Lyman-α line is produced as
electrons move between two energy levels in a hydrogen atom. The
wavelength of the light is shifted towards the red end of the spectrum
by an amount that is related to the motion and distance of the source
from which it is emitted. As this 'redshift' is greater the older the
object being observed, it allows astronomers to calculate an object's
age. Using the ground-based Very Large Telescope in Paranal, Chile, the
team detected the line, and calculated that it had a redshift of 8.55,
indicating that the light had travelled around 600 million years to
“They are really
pushing the instrumentation to its limit.”
James Dunlop, an astronomer at the
University of Edinburgh, UK, who was part of the team that found the
galaxy candidate in the Hubble data, says the result is "exciting, if
proved correct". But he adds that it is also "slightly controversial"
because it is based on the discovery of just one spectral line, making
it tough to establish that this is not just an artefact of the measuring
process. "They are really pushing the instrumentation to its limit,"
Lehnert emphasizes that the team took pains to rule out the
possibility that the line was caused by background contamination from
molecules in Earth's atmosphere. "It took months for us to convince
ourselves that this is real," he says.
The galaxy seems to confirm astronomers' models
of the early Universe, which predict that young galaxies were
responsible for reionization around 600 million years after the Big Bang4,
says Martin Haehnelt, a cosmologist at the University of Cambridge, UK.
But he notes that typical galaxies do not produce Lyman-α lines that
are as strong as the one seen by Lehnert's group, making the finding
Lehnert's team argues that the line may be unusually strong because
there are additional, as yet undetected, galaxies surrounding the newly
discovered one, giving it a helping hand in reionization. "This could
help explain it, but even then, the strength is still surprisingly
large," says Haehnelt. "This is a very nice result, but it is important
to be cautious about it."
It will be difficult to investigate the galaxy further using
ground-based telescopes, as the data will be contaminated by 'noise'
from Earth's atmosphere. However, the James Webb Space Telescope, due to
launch in 2015, will train its spectrographic instruments on this
region, in an effort to delve even further back into the Universe's
infancy. It will also help astronomers to unpick the puzzle of the
strength of the Lyman-α line, by revealing exactly what kind of galaxies
are responsible for reionization, says Dunlop. "This is the sort of
galactic archaeology that the next generation of telescopes will be able
to do," he adds.
- Lehnert M. D. et al.
Nature 467, 940-942 (2010).
- Iye, M. et al.
Nature 443, 186-188 (2006).
- McLure, R. J. et al.
Mon. Not. R. Astron. Soc. 403, 960-983 (2010).
- Choudhury, T. R. , Haehnelt, M. G. & Regan, J. Mon. Not. R. Astron. Soc. 394, 960-977 (2009).
Oldest Material in Solar System Found
Discovery suggests exploding star kick-started
An artist's conception of a young star
system, before its dusty disk has coalesced into rocky bodies.
Image courtesy NASA
for National Geographic News
Published August 23, 2010
Pea-size minerals inside a meteorite are the oldest known
material in the solar
system, a new study says.
4,568.2 million years old, the minerals push back the birth of the
solar system by as much as two million years—and suggests that an
exploding star injected key materials into our system as it was being
born, researchers say.
Rings as Old as Solar System, Study Says.")
3-pound (1.5-kilogram) parent meteorite, dubbed NWA 2364, was found in
2004 in Morocco
and is believed to have originated from the asteroid belt between Mars
the tests reveal that telltale mineral lumps inside—called
calcium-aluminum inclusions—are from a time before that asteroid belt
existed. The minerals may have formed just after part of an interstellar
gas and dust cloud, or nebula, had collapsed and formed our sun,
as one sun-formation theory goes.
"Soon after the collapse of the
solar nebula, matter started to condense as the temperature went down,
and these inclusions started forming," said lead study author Audrey Bouvier, a
research associate at Arizona State University's Center for Meteorite
Bouvier and co-author Meenakshi Wadhwa, also of Arizona
State, measured ratios of lead isotopes—lighter-or-heavier-than-usual
versions of an element—in a single "pristine" inclusion to uncover its
birth date, she said.
"This revised age is between 0.3 and 1.9
million years older than previous estimates," she said, "making it the
oldest on record."
(Also see "Oldest
Rocks on Earth Discovered?")
Blasted Solar System Into Existence?
Two million years
is a drop in the bucket in cosmic time, but it could have major
ramifications for how scientists think the solar system was born.
it comes down to isotopes—in this case, iron-60, which forms when
massive stars go supernova, exploding at the ends of their lives.
studies by other scientists of iron-60 isotopes in mineral inclusions
in meteorites found that the inclusions had formed roughly two million
years after what was thought to have been the birth of the solar system.
But because the solar system is now apparently up to
two million years older than previously thought, the abundance of
iron-60 estimated from the inclusions must be extrapolated back another
two million years. Since iron-60 degrades by half every two million
years, the revised initial quantity of iron-60 in the solar system is
almost double previous estimates.
The only thing that could have
put so much iron-60 into the nascent solar system, she added, is a
true, the finding supports a theory that a supernova seeded the ancient
solar nebula with heavy metals and possibly triggered its collapse
nearly 4.57 billion years ago.
Beginning Blast Seen in 3-D—A First.")
"I think it is
important that people understand that this matter now present in our
solar system has been brought in by other stars," Bouvier said.
stars may have exploded nearby but not close enough to destroy it—but
instead brought in these key elements for planet formation and life."
an insider's take on space news, check National Geographic's Breaking
Orbit blog >>The findings on the ancient solar
system material were published August 22 in the journal Nature Geoscience
From UniverseToday.com for 2010 June 10
Written by Nancy Atkinson
Hale-Bopp. Credit: E. Kolmhofer, H. Raab; Johannes-Kepler-Observatory,
Most comets are thought to
have originated great distances away, traveling to the inner solar system
from the Oort Cloud. But new
computer simulations show that many comets – including some famous ones –
came from even farther: they may have been born in other solar systems. Many of
the most well known comets, including Hale-Bopp (above), Halley, and,
most recently, McNaught, may have formed around other stars and then were
gravitationally captured by our Sun when it was
still in its birth cluster. This new finding solves the mystery of how
the Oort cloud formed and why it is so heavily populated with comets.
Comets are believed to be leftovers
from the formation of the solar system. They are
observed to come to the solar system from
all directions, so astronomers have thought the comet's origin was from
the Oort Cloud, a giant sphere surrounding the solar system. Some
comets travel over 100,000 AU, in a huge orbit around the sun.
comets may have formed around other stars in the cluster where the sun was born and been
captured gravitationally by our sun.
Dr. Hal Levison from the
Southwest Research Insitutue, along with Dr. Martin Duncan from Queen's
University, Kingston, Canada, Dr. Ramon Brasser, Observatoire de la Côte
d'Azur, France and Dr. David Kaufmann (SwRI) used computer simulations
to show that the Sun may have captured small icy bodies from its sibling
stars while still in its star-forming nursery
The researchers investigated what fraction of comets
might be able to travel from the outer reaches of one star to the outer
reaches of another. The simulations imply that a substantial number of
comets can be captured through this mechanism, and that a large number
of Oort cloud comets come from other stars. The results may explain why
the number of comets in the Oort cloud is larger than models predict.
the Sun currently has no companion stars, it is believed to have formed
in a cluster containing hundreds of closely packed stars that were
embedded in a dense cloud of gas. During this time, each star formed a
large number of small icy bodies (comets) in a disk from which planets formed. Most
of these comets were gravitationally slung out of these prenatal
planetary systems by the newly forming giant planets,
becoming tiny, free-floating members of the cluster.
cluster came to a violent end, however, when its gas was blown out by
the hottest young stars. These new
models show that the Sun then gravitationally captured a large cloud of
comets as the cluster dispersed.
"When it was young, the Sun
shared a lot of spit with its siblings, and we can see that stuff
today," said Levison.
"The process of capture is surprisingly
efficient and leads to the exciting possibility that the cloud contains a
potpourri that samples material from a large number of stellar siblings
of the Sun," said co-author Duncan.
Evidence for the team's
scenario comes from the roughly spherical cloud of comets, known as the
Oort cloud, that surrounds the Sun, extending halfway to the nearest star. It
has been commonly assumed this cloud formed from the Sun's
proto-planetary disk. However, because detailed models show that comets
from the solar system produce a much more anemic cloud than observed,
another source is required.
"If we assume that the Sun's observed
proto-planetary disk can be used to estimate the indigenous population
of the Oort cloud, we can conclude that more than 90 percent of the
observed Oort cloud comets have an extra-solar origin," Levison said.
formation of the Oort cloud has been a mystery for over 60 years and
our work likely solves this long-standing problem," said Brasser.
of the Sun's Oort Cloud from Stars in its Birth Cluster," was published
in the June 10 issue of Science Express.
THE ASTRONOMY PICTURE OF THE DAY FOR 2009 April 28
GRB 090423: The Farthest Explosion Yet Measured
Gemini Observatory /
D. Fox &
(Penn State U.), and
An explosion so powerful it was seen clear across the visible universe
was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory.
Farther than any known
quasar, or optical
gamma-ray burst recorded last week was clocked at
redshift 8.2, making it the farthest explosion of any type
Occurring only 630 million years after the
GRB 090423 detonated so early that astronomers had no direct evidence that anything explodable even existed back then.
The faint infrared afterglow of
GRB 090423 was recovered by large ground telescopes within minutes of being discovered.
The afterglow is circled in the above picture taken by the large
Gemini North Telescope in
An exciting possibility is that this
gamma-ray burst occurred in one of the very
first generation of stars and
announced the birth of an early
provides unique data from a relatively
unexplored epoch in our universe and a distant beacon from which the intervening universe can be studied.
FROM NASA ----------> THIS PLANET SMELLS FUNNY
Sept. 13, 2010: Giant planet GJ 436b in the Constellation Leo is missing something.
Would you Believe Swamp Gas?
To the surprise of astronomers who have been studying the
Neptune-sized planet using NASA's Spitzer Space Telescope, GJ 436b has
very little methane (CH4).
"Methane should be abundant on a planet of this temperature and
size, but we found 7000 times less methane than what the models
predict," says Kevin Stevenson of the University of Central Florida
(UCF). Stevenson was lead author of a paper reporting the result in the
April 22, 2010, issue of Nature.
An artist's concept of GJ 436b peeking out from behind its
parent star, an M-dwarf much cooler than the sun. [larger
The methane deficit is surprising because in our own solar system
all gas giants are methane-rich. Hydrogen and carbon are abundant in the
atmospheres of Jupiter, Saturn, Uranus and Neptune. These atoms
naturally get together to form the simplest hydrocarbon, CH4.
The example of our local gas giants shaped expectations when
Stevenson and colleagues pointed Spitzer in the direction of GJ 436b,
only 33 light-years away. Finding methane was a foregone conclusion. But
when the researchers analyzed the planet's spectrum, they found little
of it. Instead, the atmosphere was rich in carbon monoxide.
"Actually, it blew our minds," says principal investigator and
co-author Joseph Harrington, also of UCF.
Where did all the methane go? One possibility: it's being broken
apart. "UV radiation from the planet's star could be converting the
methane into polymers like ethylene," says Harrington. "If you put
plastic wrap out in the sun, the UV radiation breaks down the carbon
bonds in the plastic, causing it to deteriorate as the long carbon
chains break. We propose a similar process on GJ 436b, but there
hydrogen atoms split off from methane and let the remnants stick
together to make ethylene (C2H4)."
A stick-figure diagram of methane. [more]
Also, they speculate, strong vertical winds in the planet's
atmosphere might be sweeping up material from deep hot layers where
carbon monoxide is abundant. CO thus replaces CH4.
Or it could be something else entirely.
"This planet's atmosphere could have some sort of alien chemistry
going on," says Harrington. "We just don't know yet."
Giant planets aren't the only worlds with methane. CH4
is fairly common on Earth, too. Methane forms in the stomachs of cows
and goats. It also bubbles up from the bottom of swamps, a byproduct of
organic matter decaying in deep mud. On gas giants, methane is just
common chemistry, but on our planet, it is a sign of life.
For this reason, researchers have long planned to look for methane
in the atmospheres of distant Earth-sized planets. NASA's Kepler
mission is expected to discover many Earth-sized planets over the next
few years, so the scientists will have plenty of promising targets to
pursue. Methane floating alongside oxygen could be compelling evidence
of biological activity.
But what if planetary atmospheres don't always follow the rules of
our own Solar System? GJ 436b certainty doesn't. Investigators might
have to go back to the drawing board and re-figure their chemistry.
"GJ 436b is telling us something important," says Harrington:
"We’re not in Kansas anymore."
Tony Phillips, Dauna
Coulter | Credit: Science@NASA
Other authors of the Nature paper reporting this result
include: Sarah Nymeyer, William C. Bowman, Ryan A. Hardy and Nate B.
Lust from the University of Central Florida; Nikku Madhusudhan and Sara
Seager of the Massachusetts Institute of Technology, Cambridge; Drake
Deming of NASA's Goddard Space Flight Center, Greenbelt, Md.; and Emily
Rauscher of Columbia University, New York.
JPL manages the Spitzer Space Telescope
mission for NASA's Science Mission Directorate, Washington. Science
operations are conducted at the Spitzer Science Center at Caltech.
Caltech manages JPL for NASA.
LIGHTEST EXOPLANET DISCOVERED --
Gliese 581 e (pronounced /ˈɡliːzə/) is the fourth extrasolar planet found around Gliese 581, an M3V red dwarf star approximately 20 light-years away from Earth in the constellation of Libra. At a minimum of 1.9 Earth masses,
it is the smallest extrasolar planet discovered around a normal star,
and the closest in mass to Earth, though at an orbital distance of just
0.03 AU from its parent star it is well out of the habitable zone, and is unlikely to possess an atmosphere due to its high temperature, small size, and strong radiation from the star.
The planet was discovered by the team of Michel Mayor of the Observatory of Geneva in Switzerland using the HARPS instrument on the European Southern Observatory 3.6 meter telescope in La Silla, Chile. The discovery was announced on 21 April 2009. Mayor's team employed the radial velocity technique, in which the orbit size and mass of a planet are determined based on the small perturbations it induces in its parent star's orbit via gravity.
EUROPEAN SOUTHERN OBSERVATORY (ESO) 15/09 - Science Release
21 April 2009
For Immediate Release
Lightest exoplanet yet Discovered
Well-known exoplanet researcher Michel Mayor today
announced the discovery of the lightest exoplanet found so far. The
planet, “e”, in the famous system Gliese 581, is only about twice the
mass of our Earth. The team also refined the orbit of the planet Gliese
581 d, first discovered in 2007, placing it well within the habitable
zone, where liquid water oceans could exist. These amazing discoveries
are the outcome of more than four years of observations using the most
successful low-mass-exoplanet hunter in the world, the HARPS
spectrograph attached to the 3.6-metre ESO telescope at La Silla,
“The holy grail of current exoplanet research is the detection
of a rocky, Earth-like planet in the ‘habitable zone’ — a region around
the host star with the right conditions for water to be liquid on a
planet’s surface”, says Michel Mayor from the Geneva Observatory, who led the European team to this stunning breakthrough.
Planet Gliese 581 e orbits its host star – located only 20.5
light-years away in the constellation Libra (“the Scales”) — in just
3.15 days. “With only 1.9 Earth-masses, it is the least massive exoplanet ever detected and is, very likely, a rocky planet”, says co-author Xavier Bonfils from Grenoble Observatory.
Being so close to its host star, the planet is not in the habitable
zone. But another planet in this system appears to be. From previous
observations — also obtained with the HARPS spectrograph at ESO’s La
Silla Observatory and announced two years ago — this star was known to
harbour a system with a Neptune-sized planet (ESO 30/05) and two super-Earths (ESO 22/07).
With the discovery of Gliese 581 e, the planetary system now has four
known planets, with masses of about 1.9 (planet e), 16 (planet b), 5
(planet c), and 7 Earth-masses (planet d). The planet furthest out,
Gliese 581 d, orbits its host star in 66.8 days. “Gliese 581 d is
probably too massive to be made only of rocky material, but we can
speculate that it is an icy planet that has migrated closer to the star,”
says team member Stephane Udry. The new observations have revealed that
this planet is in the habitable zone, where liquid water could exist. “‘d’ could even be covered by a large and deep ocean — it is the first serious 'water world' candidate,” continued Udry.
The gentle pull of an exoplanet as it orbits the host star
introduces a tiny wobble in the star’s motion — only about 7 km/hour,
corresponding to brisk walking speed — that can just be detected on
Earth with today’s most sophisticated technology. Low-mass red dwarf
stars such as Gliese 581 are potentially fruitful hunting grounds for
low-mass exoplanets in the habitable zone. Such cool stars are
relatively faint and their habitable zones lie close in, where the
gravitational tug of any orbiting planet found there would be stronger,
making the telltale wobble more pronounced. Even so, detecting these
tiny signals is still a challenge, and the discovery of Gliese 581 e
and the refinement of Gliese 581 d’s orbit were only possible due to
HARPS’s unique precision and stability.
“It is amazing to see how far we have come since we discovered
the first exoplanet around a normal star in 1995 — the one around 51
Pegasi,” says Mayor. “The mass of Gliese 581 e is 80 times less than that of 51 Pegasi b. This is tremendous progress in just 14 years.”
The astronomers are confident that they can still do better. “With
similar observing conditions an Earth-like planet located in the middle
of the habitable zone of a red dwarf star could be detectable,” says Bonfils. “The hunt continues.”
This discovery was announced today at the JENAM conference during
the European Week of Astronomy & Space Science, which is taking
place at the University of Hertfordshire, UK. The results have also
been submitted for publication in the research journal Astronomy &
Astrophysics (“The HARPS search for southern extra-solar planets:
XVIII. An Earth-mass planet in the GJ 581 planetary system”, by Mayor
et al., 2009).
The team is composed of M. Mayor, S. Udry, C. Lovis, F. Pepe and D.
Queloz (Geneva Observatory, Switzerland), X. Bonfils, T. Forveille , X.
Delfosse, H. Beust and C. Perrier (LAOG, France), N. C. Santos (Centro
de Astrofisica,Universidade de Porto), F. Bouchy (IAP, Paris, France)
and J.-L. Bertaux (Service d’Aéronomie du CNRS, Verrières-le-Buisson,
ESO, the European Southern Observatory, is the foremost
intergovernmental astronomy organisation in Europe. It is supported by
14 countries: Austria, Belgium, the Czech Republic, Denmark, France,
Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden,
Switzerland and the United Kingdom. ESO carries out an ambitious
program focused on the design, construction and operation of powerful
ground-based observing facilities enabling astronomers to make
important scientific discoveries. ESO also plays a leading role in
promoting and organising cooperation in astronomical research. ESO
operates three unique world-class observing sites in the Atacama Desert
region of Chile: La Silla, Paranal and Chajnantor.
Geneva University, Switzerland
E-mail: michel.mayor (at) unige.ch
Prof. Mayor will attend the JENAM conference from 20 to 21 April and can be reached by phone through the JENAM press center.
Xavier Bonfils, Thierry Forveille
Grenoble Observatory, France
Phone: +33 476 63 55 27, +33 4 76 51 42 06
E-mail: xavier.bonfils (at) obs.ujf-grenoble.fr, thierry.forveille(at)obs.ujf-grenoble.fr
Geneva University, Switzerland
Phone: +41 22 379 2467
E-mail: stephane.udry (at) unige.ch
ESO La Silla - Paranal - ELT Press Officer: Dr. Henri Boffin - +49 89 3200 6222 - firstname.lastname@example.org
ESO Press Officer in Chile: Valentina Rodriguez - +56 2 463 3123 - email@example.com
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Dr. Paola Rebusco
From Wikipedia, the free encyclopedia
COROT-Exo-7b is an exoplanet orbiting around the star CoRoT-Exo-7. It was detected by the French-led COROT mission in 2009. It is the smallest exoplanet to have its diameter measured, at 1.7 times that of the Earth. Its mass is estimated to be 5–10 earth masses. It orbits very close to its star with an orbital period of 20 hours. The star, in the constellation Monoceros, is 390 light-years (120 pc) away and is slightly smaller than the Sun.
The planet has a high surface temperature, between 1000 to 1500 °C. Due to the high temperature, it may be covered in lava or water vapor. The composition and density of the planet are still being examined, with one possibility being that it is rocky
like Earth. It may also belong to a class of planets that are thought
to be made up of water vapor and rock in almost equal amounts.
The scientists are unsure whether it is an ocean planet, a kind of planet whose existence has yet to be proven so far. In theory, such planets would initially be covered partially in ice and they would later drift towards their star, with the ice melting to cover it in liquid.
With an orbital period of just 20 hours, the planet has the shortest orbit yet seen in an extrasolar planet.
According to Suzanne Aigrain, a researcher at the University of Exeter
who is part of the CoRoT team, the planet is much more earthlike than
previously found exoplanets and probably has a solid surface somewhere.
COROT-Exo-7b was found by the observation of a brightness change of
its mother star, originating in a transit of the planet in front of the
star (as seen from Earth). The exact knowledge of the brightness
difference, together with a size estimate for the star, allows one to
calculate the planet's size.
The discovery of CoRoT-Exo-7b was announced on 2009 February 3, during the CoRoT Symposium 2009 in Paris. It will be published in a forthcoming special issue of the journal Astronomy and Astrophysics dedicated to results from CoRoT.
The planet's current name is derived from the COROT mission, which stands for "COnvection ROtation and planetary Transits". It is led by the French Space Agency CNES with involvement by the European Space Agency, Austria, Belgium, Germany, Spain, and Brazil.
COMET LULIN -- C/2007 N3
From Wikipedia, the free encyclopedia
NOTE THAT AU MEANS ASTRONOMICAL UNIT WHICH EQUALS 92,955,807 MILES - THE EARTH-SUN AVERAGE DISTANCE. THE ECCENTRICITY LISTED BELOW BEING MORE THAN 1 REFERS TO A HYPERBOLIC ORBIT WHICH INDICATES A GREAT MAXIMUM DISTANCE WHICH REACHES INTO THE OORT COMET CLOUD
THE COMET IS NOW WITHIN THE REACH OF ORDINARY BINOCULARS AND HAS JUST BEEN REPORTED SEEN WITH THE NAKED EYE
IN THE GOOD SKIES OF RURAL LOCATIONS ON 2009 FEBRUARY 6
Comet C/2007 N3 (Lulin), also known as Comet Lulin, is a non-periodic comet. It was discovered by Ye Quanzhi and Lin Chi-Sheng from Lulin Observatory. It will peak in brightness for observers on Earth on February 24, 2009, between magnitude +4 and magnitude +6. The comet will also pass near Saturn on February 23, will also appear to pass near and near Regulus in Leo on February 26 and 27, 2009. On May 12, 2009, it will then appear to pass near Comet Cardinal. It currently appears at magnitude +8.2, in the constellation Scorpius.
COMET LULIN's PATH BELOW FROM DISCOVERY TO END OF FEB 2009
COMET LULIN's PATH BELOW FROM MID-FEB 2009 TO MARCH 2010
COMET LULIN's BRIGHTNESS FOR DATA TO VERTICAL PINK LINE FOLLOWED BY PREDICTION OF BRIGHTNESS PEAK NEAR 4 th MAG BY LATE FEB 2009
- ^ a b c Kronk, Gary W.. "C/2007 N3 (Lulin)". cometography.com. Retrieved on 2009-01-02.
- ^ a b c d e Yoshida, Seiichi (December 31, 2008). "C/2007 N3 ( Lulin )" (in English). aerith.net. Retrieved on 2009-01-02.
- ^ a b c d e f "JPL Small-Body Data (C/2007 N3)". JPL NASA. Retrieved on 2009-01-02.
- ^ Yeomans, Donald K.. "Horizon Online Ephemeris System". California Institute of Technology, Jet Propulsion Laboratory. Retrieved on 2009-01-02.
- ^ a b c Dyer, Alan (2009). "Venus Kicks Off the Year of Astronomy (pg. 24-27)". in Dickinson, Terence. SkyNews: The Canadian Magazine on Astronomy & Stargazing. XIV, Issue 5 (January/February 2009 ed.). Yarker, Ontario: SkyNews Inc. pp. 38.
- ^ Dyer, Alan (2009). "The Top 10 Celestial Sights of 2009 (pg. 14)". in Dickinson, Terence. SkyNews: The Canadian Magazine of Astronomy & Stargazing. XIV, Issue 5 (January/February 2009 ed.). Yarker, Ontario: SkyNews Inc. pp. 38.
- ^ Peat, Chris. "Comet C/2007 N3 Lulin". Heavens-Above GmbH. Heavens-Above.com. Retrieved on 2009-01-07.
Solar Wind Rips
Up Martian Atmosphere
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21, 2008: Researchers have found new evidence that
the atmosphere of Mars is being stripped away by solar wind.
It's not a gently continuous erosion, but rather a ripping
process in which chunks of Martian air detach themselves from
the planet and tumble into deep space. This surprising mechanism
could help solve a longstanding mystery about the Red Planet.
helps explain why Mars has so little air," says David
Brain of UC Berkeley, who presented the findings at the 2008
Huntsville Plasma Workshop on October 27th.
of years ago, Mars had a lot more air than it does today.
(Note: Martian "air" is primarily carbon dioxide,
not the nitrogen-oxygen mix we breathe on Earth.) Ancient
martian lake-beds and river channels tell the tale of a planet
covered by abundant water and wrapped in an atmosphere thick
enough to prevent that water from evaporating into space.
Some researchers believe the atmosphere of Mars was once as
thick as Earth's. Today, however, all those lakes and rivers
are dry and the atmospheric pressure on Mars is only 1% that
of Earth at sea-level. A cup of water placed almost anywhere
on the Martian surface would quickly and violently boil away—a
result of the super-low air pressure.
right: An artist's concept of ancient Mars with abundant
air and water. [Larger Image)
where did the air go? Researchers entertain several possibilities:
An asteroid hitting Mars long ago might have blown away a
portion of the planet's atmosphere in a single violent upheaval.
Or the loss might have been slow and gradual, the result of
billions of years of relentless "sand-blasting"
by solar wind particles. Or both mechanisms could be at work.
has uncovered a new possibility--a daily ripping process intermediate
between the great cataclysm and slow erosion models. The evidence
comes from NASA's now-retired Mars Global Surveyor (MGS) spacecraft.
1998, MGS discovered that Mars has a very strange magnetic
field. Instead of a global bubble, like Earth's, the Martian
field is in the form of magnetic umbrellas that sprout out
of the ground and reach beyond the top of Mars' atmosphere.
These umbrellas number in the dozens and they cover about
40% of the planet’s surface, mainly in the southern hemisphere.
years, researchers thought the umbrellas protected the Martian
atmosphere, shielding pockets of air beneath them from erosion
by the solar wind. Surprisingly, Brain finds that the opposite
can be true as well: "The umbrellas are where coherent
chunks of air are torn away."
Solar wind blowing against Mars tears atmosphere-filled plasmoids
from the tops of magnetic umbrellas. Credit: Graphic artist
Steve Bartlett. [Larger
his colleagues at the Workshop, he described how he made the
discovery just a few months ago:
was scrolling through archival data from Global Surveyor's
particles and fields sensors. "We have measurements from
25,000 orbits," he says. During
one of those orbits, MGS passed through the top of a magnetic
umbrella. Brain noticed that the umbrella's magnetic field
had linked up with the magnetic field in the solar wind. Physicists
call this "magnetic reconnection." What happened
next is not 100% certain, but Global Surveyor's readings are
consistent with the following scenario: "The joined fields
wrapped themselves around a packet of gas at the top of the
Martian atmosphere, forming a magnetic capsule a thousand
kilometers wide with ionized air trapped inside," says
Brain. "Solar wind pressure caused the capsule to 'pinch
off' and it blew away, taking its cargo of air with it."
Brain has since found a dozen more examples. The magnetic
capsules or "plasmoids" tend to blow over the south
pole of Mars, mainly because most of the umbrellas are located
in Mars' southern hemisphere.
Dave Brain of UC Berkeley presented this slide at the 2008
Huntsville Plasma Workshop to explain in cartoon fashion how
plasmoids carry air away from Mars. [Larger
isn't ready to declare the mystery solved. "We're still
not sure how often the plasmoids form or how much gas each
one contains." The problem is, Mars Global Surveyor wasn't
designed to study the phenomenon. The spacecraft was only
equipped to sense electrons, not the heavier ions which would
make up the bulk of any trapped gas. "Ions and electrons
don't always behave the same way," he cautions. Also,
MGS sampled the umbrellas at fixed altitudes and at the same
local time each day. "We need to sample many altitudes
and times of day to truly understand these dynamic events."
short, he told the audience, "we need more data."
is pinning his hopes on a new NASA mission named MAVEN. Short
for "Mars Atmosphere and Volatile Evolution," MAVEN
is an upper atmosphere orbiter currently approved for launch
to Mars in 2013. The probe is specifically designed to study
atmospheric erosion. MAVEN will be able to detect electrons,
ions and neutral atoms; it will be able to measure both magnetic
and electric fields; it will travel around Mars in an elliptical
orbit, piercing magnetic umbrellas at different altitudes,
angles, and times of day; and it will explore regions both
near and far from the umbrellas, giving researchers the complete
picture they need.
magnetized chunks of air are truly being torn free, MAVEN
will see it happening and measure the atmospheric loss rate.
"Personally, I think this mechanism is important,"
says Brain, "but MAVEN may yet prove me wrong."
the Mystery of the Missing Martian Air is shaping
up to be a ripping good yarn.
THIS STORY TO A FRIEND
Tony Phillips | Credit: Science@NASA
Rays from a Mysterious Nearby Object
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19, 2008: An international team of researchers has
discovered a puzzling surplus of high-energy electrons bombarding
Earth from space. The source of these cosmic rays is unknown,
but it must be close to the solar system and it could be made
of dark matter. Their results are being reported in the Nov.
20th issue of the journal Nature.
is a big discovery," says co-author John Wefel of Louisiana
State University. "It's the first time we've seen a discrete
source of accelerated cosmic rays standing out from the general
An artist's concept of cosmic rays hitting Earth's upper atmosphere.
Credit: Simon Swordy, University of Chicago. [Larger
cosmic rays are subatomic particles accelerated to almost
light speed by distant supernova explosions and other violent
events. They swarm through the Milky Way, forming a haze of
high energy particles that enter the solar system from all
directions. Cosmic rays consist mostly of protons and heavier
atomic nuclei with a dash of electrons and photons spicing
study the most powerful and interesting cosmic rays, Wefel
and colleagues have spent the last eight years flying a series
of balloons through the stratosphere over Antarctica. Each
time the payload was a NASA-funded cosmic ray detector named
ATIC, short for Advanced Thin Ionization Calorimeter. The
team expected ATIC to tally the usual mix of particles, mainly
protons and ions, but the calorimeter found something extra:
an abundance of high-energy electrons.
likens it to driving down a freeway among family sedans, mini-vans
and trucks—when suddenly a bunch of Lamborghinis bursts through
the normal traffic. "You don't expect to see so many
race cars on the road—or so many high-energy electrons in
the mix of cosmic rays." During five weeks of ballooning
in 2000 and 2003, ATIC counted 70 excess electrons in the
energy range 300-800 GeV. ("Excess" means over and
above the usual number expected from the galactic background.)
Seventy electrons may not sound like a great number, but like
seventy Lamborghinis on the freeway, it's a significant surplus.
ATIC high-energy electron counts. The triangular curve fitted
to the data comes from a model of dark-matter annihilation
featuring a Kaluza-Klein particle of mass near 620 GeV (620 Billion Electron Volts). Details
may be found in the Nov. 20, 2008, edition of Nature: "An
excess of cosmic ray electrons at energies of 300-800 Gev,"
by J. Chang et al. [Larger
source of these exotic electrons must be relatively close
to the solar system—no more than a kiloparsec away,"
says co-author Jim Adams of the NASA Marshall Space Flight
must the source be nearby? Adams explains: "High-energy
electrons lose energy rapidly as they fly through the galaxy.
They give up energy in two main ways: (1) when they collide
with lower-energy photons, a process called inverse Compton
scattering, and (2) when they radiate away some of their energy
by spiraling through the galaxy's magnetic field." By
the time an electron has traveled a whole kiloparsec, it isn't
so 'high energy' any more.
electrons are therefore local. Some members of the research
team believe the source could be less than a few hundred parsecs
away. For comparison, the disk of the spiral Milky Way galaxy
is about thirty thousand parsecs wide. (One parsec equals 3.263 light years.)
says Wefel, "we can't pinpoint the source in the sky."
Although ATIC does measure the direction of incoming particles,
it's difficult to translate those arrival angles into celestial
coordinates. For one thing, the detector was in the basket
of a balloon bobbing around the South Pole in a turbulent
vortex of high-altitude winds; that makes pointing tricky.
Moreover, the incoming electrons have had their directions
scrambled to some degree by galactic magnetic fields. "The
best ATIC could hope to do is measure a general anisotropy—one
side of the sky versus the other."
The ATIC cosmic ray detector ascends to the stratosphere tethered
to a high-altitude research balloon. More launch images: #1,
uncertainty gives free rein to the imagination. The least
exotic possibilities include, e.g., a nearby pulsar, a 'microquasar'
or a stellar-mass black hole—all are capable of accelerating
electrons to these energies. It is possible that such a source
lurks undetected not far away. NASA's recently-launched Fermi
Gamma-ray Space Telescope is only just beginning to survey
the sky with sufficient sensitivity to reveal some of these
even more tantalizing possibility is dark matter.
is a class of physical theories called "Kaluza-Klein
theories" which seek to reconcile gravity with other
fundamental forces by positing extra dimensions. In addition
to the familiar 3D of human experience, there could be as
many as eight more dimensions woven into the space around
us. A popular yet unproven explanation for dark matter is
that dark matter particles inhabit the extra dimensions. We
feel their presence via the force of gravity, but do not sense
them in any other way.
does this produce excess cosmic rays? Kaluza-Klein particles
have the curious property (one of many) that they are their
own anti-particle. When two collide, they annihilate one another,
producing a spray of high-energy photons and electrons. The
electrons are not lost in hidden dimensions, however, they
materialize in the 3-dimensions of the real world where ATIC
can detect them as "cosmic rays."
data could be explained by a cloud or clump of dark matter
in the neighborhood of the solar system," says Wefel.
"In particular, there is a hypothesized Kaluza-Klein
particle with a mass near 620 GeV which, when annihilated,
should produce electrons with the same spectrum of energies
this possibility is nontrivial because dark matter is so,
well, dark. But it may be possible to find the cloud by looking
for other annihilation products, such as gamma-rays. Again,
the Fermi Space Telescope may have the best chance of pinpointing
it is," says Adams, "it's going to be amazing."
more information about this research, see "An excess
of cosmic ray electrons at energies of 300-800 Gev,"
by J. Chang et al. in the Nov. 20, 2008, issue of Nature.
THIS STORY TO A FRIEND
Tony Phillips | Credit: Science@NASA
Thin Ionization Calorimeter is an international
collaboration of researchers from Louisiana State University,
University of Maryland, Marshall Space Flight Center,
Purple Mountain Observatory in China, Moscow State University
in Russia and Max-Planck Institute for Solar System
Research in Germany. ATIC is supported in the United
States by NASA and flights are conducted under the auspices
of the Balloon Program Office at Wallops Flight Facility
by the staff of the Columbia Scientific Balloon Facility.
Antarctic logistics are provided by the National Science
Foundation and its contractor Raytheon Polar Services
Space Exploration Policy
Discovered: A New
Kind of Pulsar
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17, 2008: About three times a second, a 10,000-year-old
stellar corpse sweeps a beam of gamma-rays toward Earth. Just
discovered by NASA's Fermi Gamma-ray Space Telescope, the
object, called a pulsar, is the first one known that "blinks"
in pure gamma rays.
is the first example of a new class of pulsars," says
Stanford University's Peter Michelson, principal investigator
for Fermi's Large Area Telescope. "[We think] it will
give us fundamental insights into how these collapsed stars
An artist's concept of the newly discovered pulsar. Clouds
of charged particles move along the pulsar's magnetic field
lines (blue) and create a lighthouse-like beam of gamma rays
were first discovered
in 1967 by student radio astronomer Jocelyn Bell and her thesis
advisor Tony Hewish. The radio pulses they recorded were uncannily
steady--so much so that some astronomers wondered if they
were picking up signals from extraterrestrial civilizations.
The correct explanation was even stranger: Pulsars are spinning
neutron stars packing the mass of the sun into a sphere about
20 km across. Whirling around thousands of times each hour,
they beam radio pulses into the cosmos in the style of a rapidfire
then, about 1800 pulsars have been discovered mainly via their
radio emission. A fraction of pulsars go beyond radio; they
also emit pulses of visible light, X-rays, and even high-energy
gamma-rays. This discovery by Fermi is different because it
is a purely gamma-ray pulsar. The star is silent across parts
of electromagnetic spectrum where pulsars are normally found
and hints at a whole population of previously unsuspected pulsars
waiting to be picked out of the heavens.
gamma-ray-only pulsar lies within a supernova remnant known
as CTA 1 located about 4,600 light-years away in the constellation
Cepheus. Its lighthouse-like beam sweeps Earth's way every
316.86 milliseconds. The pulsar, which formed in a supernova
explosion about 10,000 years ago, emits 1,000 times the energy
of our sun.
Large Area Telescope provides us with a unique probe of the
galaxy's pulsar population, revealing objects we would not
otherwise even know exist," says Fermi project scientist
Steve Ritz of the Goddard Space Flight Center.
The pulsar is not located at the center of the surrounding
supernova remnant CTA 1. Click on the image to view a larger
pulsar in CTA 1 is not located at the center of the supernova's
expanding gaseous shell. Supernova explosions can be asymmetrical,
often imparting a "kick" that sends the neutron
star careening through space. Based on the remnant's age and
the pulsar's distance from its center, astronomers believe
the neutron star is moving at about a million miles per hour
-- a typical speed for neutron stars.
Large Area Telescope scans the entire sky every three hours
and detects photons with energies ranging from 20 million
to more than 300 billion times the energy of visible light.
observation shows the power of the Large Area Telescope,"
Michelson adds. "It is so sensitive that we can now discover
new types of objects just by observing their gamma-ray emissions."
paper about the new pulsar appears in the Oct. 16 edition
of Science Express.
THIS STORY TO A FRIEND
Tony Phillips | Credit: Science@NASA
Gamma-ray Telescope -- Mission Home Page
Fermi mission is an astrophysics and particle physics
partnership, developed in collaboration with the U.S.
Department of Energy, along with important contributions
from academic institutions and partners in France, Germany,
Italy, Japan, Sweden, and the U.S.
Space Exploration Policy
Reconnaissance Orbiter Reveals Details of a Wetter Mars
Mars Reconnaissance Orbiter has revealed Martian rocks containing a
hydrated mineral similar to opal. Image credit: NASA/JPL-Caltech/Univ.
-- NASA's Mars Reconnaissance Orbiter has observed a new
category of minerals spread across large regions of Mars. This
discovery suggests that liquid water remained on the planet's surface a
billion years later than scientists believed, and it played an
important role in shaping the planet's surface and possibly hosting
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Researchers examining data from the orbiter's
Compact Reconnaissance Imaging Spectrometer for Mars have found
evidence of hydrated silica, commonly known as opal. The hydrated, or
water-containing, mineral deposits are telltale signs of where and when
water was present on ancient Mars.
"This is an exciting discovery because it extends the time range
for liquid water on Mars, and the places where it might have supported
life," said Scott Murchie, the spectrometer's principal investigator at
the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.
"The identification of opaline silica tells us that water may have
existed as recently as 2 billion years ago."
Until now, only two major groups of hydrated minerals,
phyllosilicates and hydrated sulfates, had been observed by spacecraft
orbiting Mars. Clay-like phyllosilicates formed more than 3.5 billion
years ago where igneous rock came into long-term contact with water.
During the next several hundred million years, until approximately 3
billion years ago, hydrated sulfates formed from the evaporation of
salty and sometimes acidic water.
The newly discovered opaline silicates are the youngest of the
three types of hydrated minerals. They formed where liquid water
altered materials created by volcanic activity or meteorite impact on
the Martian surface. One such location noted by scientists is the large
Martian canyon system called Valles Marineris.
"We see numerous outcrops of opal-like minerals, commonly in thin
layers extending for very long distances around the rim of Valles
Marineris and sometimes within the canyon system itself," said Ralph
Milliken of NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Milliken is lead author of an article in the November issue of
"Geology" that describes the identification of opaline silica. The
study reveals that the minerals, which also were recently found in
Gusev Crater by NASA's Mars rover Spirit, are widespread and occur in
relatively young terrains.
In some locations, the orbiter's spectrometer observed opaline
silica with iron sulfate minerals, either in or around dry river
channels. This indicates the acidic water remained on the Martian
surface for an extended period of time. Milliken and his colleagues
believe that in these areas, low-temperature acidic water was involved
in forming the opal. In areas where there is no clear evidence that the
water was acidic, deposits may have formed under a wide range of
"What's important is that the longer liquid water existed on Mars,
the longer the window during which Mars may have supported life," says
Milliken. "The opaline silica deposits would be good places to explore
to assess the potential for habitability on Mars, especially in these
The spectrometer collects 544 colors, or wavelengths, of reflected
sunlight to detect minerals on the surface of Mars. Its highest
resolution is about 20 times sharper than any previous look at the
planet in near-infrared wavelengths.
Provided by NASA
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Closest Planetary System Hosts Two Asteroid Belts
The closest known planetary system to our
own is called Epsilon Eridani. Image credit: NASA/JPL-Caltech Full image and caption
October 27, 2008
New observations from NASA's Spitzer Space Telescope indicate that the
nearest planetary system to our own has two asteroid belts. Our own
solar system has just one.
The star at the center of the nearby system, called Epsilon
Eridani, is a younger, slightly cooler and fainter version of the sun.
Previously, astronomers had uncovered evidence for two possible planets
in the system, and for a broad, outer ring of icy comets similar to our
own Kuiper Belt.
Now, Spitzer has discovered that the system also has dual
asteroid belts. One sits at approximately the same position as the one
in our solar system. The second, denser belt, most likely also
populated by asteroids, lies between the first belt and the comet ring.
The presence of the asteroid belts implies additional planets in the
Epsilon Eridani system.
"This system probably looks a lot like ours did when life
first took root on Earth," said Dana Backman, an astronomer at the SETI
Institute, in Mountain View, Calif., and outreach director for NASA's
Sofia mission. "The main difference we know of so far is that it has an
additional ring of leftover planet construction material." Backman is
lead author of a paper about the findings to appear Jan. 10 in the
Asteroid belts are rocky and metallic debris left over from
the early stages of planet formation. Their presence around other stars
signals that rocky planets like Earth could be orbiting in the system's
inner regions, with massive gas planets circling near the belts' rims.
In our own solar system, for example, there is evidence that Jupiter,
which lies just beyond our asteroid belt, caused the asteroid belt to
form long ago by stirring up material that would have otherwise
coalesced into a planet. Nowadays, Jupiter helps keep our asteroid belt
confined to a ring.
Astronomers have detected stars with signs of multiple belts
of material before, but Epsilon Eridani is closer to Earth and more
like our sun overall. It is 10 light-years away, slightly less massive
than the sun, and roughly 800 million years old, or one-sixth the age
of the sun.
Because the star is so close and similar to the sun, it is
a popular locale in science fiction. The television series Star Trek
and Babylon 5 referenced Epsilon Eridani, and it has been featured in
novels by Isaac Asimov and Frank Herbert, among others.
The popular star was also one of the first to be searched
for signs of advanced alien civilizations using radio telescopes in
1960. At that time, astronomers did not know of the star's young age.
Spitzer observed Epsilon Eridani with both of its infrared
cameras and its infrared spectrometer. When asteroid and comets collide
or evaporate, they release tiny particles of dust that give off heat,
which Spitzer can see. "Because the system is so close to us, Spitzer
can really pick out details in the dust, giving us a good look at the
system's architecture," said co-author Karl Stapelfeldt of NASA's Jet
Propulsion Laboratory, Pasadena, Calif.
The asteroid belts detected by Spitzer orbit at distances
of approximately 3 and 20 astronomical units from the star (an
astronomical unit is the average distance between Earth and the sun).
For reference, our own asteroid belt lies at about 3 astronomical units
from the sun, and Uranus is roughly 19 astronomical units away. An Astronomical Unit represents the average distance of the Earth to our Sun - 92,955,807 miles.
One of the two possible planets previously identified
around Epsilon Eridani, called Epsilon Eridani b, was discovered in
2000. The planet is thought to orbit at an average distance of 3.4
astronomical units from the star -- just outside the innermost asteroid
belt identified by Spitzer. This is the first time that an asteroid
belt and a planet beyond our solar system have been found in a similar
arrangement as our asteroid belt and Jupiter.
Some researchers had reported that Epsilon Eridani b orbits
in an exaggerated ellipse ranging between 1 and 5 astronomical units,
but this means the planet would cross, and quickly disrupt, the
newfound asteroid belt. Instead, Backman and colleagues argue that this
planet must have a more circular orbit that keeps it just outside the
The other candidate planet was first proposed in 1998 to
explain lumpiness observed in the star's outer comet ring. It is
thought to lie near the inner edge of the ring, which orbits between 35
and 90 astronomical units from Epsilon Eridani.
The intermediate belt detected by Spitzer suggests that a
third planet could be responsible for creating and shepherding its
material. This planet would orbit at approximately 20 astronomical
units and lie between the other two planets. "Detailed studies of the
dust belts in other planetary systems are telling us a great deal about
their complex structure," said Michael Werner, co-author of the study
and project scientist for Spitzer at JPL. "It seems that no two
planetary systems are alike."
JPL manages the Spitzer mission for NASA's Science Mission
Directorate, Washington. Science operations are conducted at the
Spitzer Science Center at the California Institute of Technology in
Pasadena. Caltech manages JPL for NASA. More information about Spitzer
is at www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer . More information about extrasolar planets and NASA's planet-finding program is at http://planetquest.jpl.nasa.gov .
Media contact: Whitney Clavin 818-354-4673
Jet Propulsion Laboratory
Bizarre Exoplanet Found by CoRoT: The
little space observatory COROT has discovered a massive planet-sized
object orbiting its parent star closely, unlike anything ever spotted
before. It is so exotic, that scientists are unsure as to whether this
oddity is actually a planet or a failed star. The object, named
COROT-exo-3b, is about the size of Jupiter, but packs more than 20
times the mass. It takes only 4 days and 6 hours to orbit its parent
star, which is slightly larger than the Sun. This odd find does not
fall into either planets or conventional category of brown dwarfs.
COROT-exo-3b might turn out to be a rare object found by sheer luck.
But it might just be a member of a new-found family of very massive
planets that encircle stars more massive than our Sun. The more massive
the star, the more massive the planet? As a planet, COROT-exo-3b would
be the most massive and the densest found to date - more than twice as
dense as lead. Studying it will help them better understand how to
categorize such objects .
Density Higher Than Lead!