Programs 241-270


241-Could Be Twins

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Published PRX April 8, 2016
Recorded April 05, 2016

It is hard to have a personal feel for the microgravity of a comet since it is only a few ten thousandths of the pull of gravity we experience on Earth. When a comet comes near Jupiter or perhaps the Earth the tiny gravity which holds it together can be overwhelmed by gravity of the larger object and the comet's structure disrupted.

Astronomers have observed comets breaking up into smaller pieces as they orbit the Sun. In a spectacular example, more than 20 years ago Comet Shoemaker-Levy 9 became a beautiful string of comets before it crashed into Jupiter. 

Recently on two consecutive days, Comet P/2016 BA14 (PANSTARRS) and Comet 252P (LINEAR) both passed within a few million miles of planet Earth. These two objects have remarkably similar orbits which take them from near Earth out to close to the giant planet Jupiter. This situation suggests that the smaller of the two, P/2016 BA14, could be a fragment of Comet 252P which calved off of the parent object during a previous close encounter with Jupiter, Mars, or the Earth.

Currently, Astronomers are using data from the Hubble Space Telescope and NASA's Infrared telescope in Hawaii to look for clues as to the nature of these potentially twin objects.

Comet 252P and P/2016 BA14 will not come this close to Earth again for millennia and are not threat to Earth. What makes them unusual is the opportunity given to humans to study these wanderers of the solar system relatively close up and personal.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 241 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

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242-Spray Paint

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Published PRX April 8, 2016
Recorded April 05, 2016

Recently, NASA scientists using the giant RADAR telescope in Puerto Rico measured changes in the orbit of the asteroid Bennu. They found that a tiny sunlight pressure of 1/2 oz on this 68 million ton object has changed it's orbit about a hundred miles over a 12 year period of time. These NASA astronomers thus measured the Yarkovsky force which was first suggested by a Russian engineer more than a hundred years ago. This Yarkovsky force, named for its proposer, occurs because sunlight absorbed by an object in space is reradiated in a directional way and thus acts like a tiny rocket motor. It is likely that, over the eons,  this tiny effect has changed the course of families of asteroids between Mars and Jupiter causing some of them to be sent in our direction.

This leads to the question "Is it possible that the world could be saved by spray paint?" Well maybe.
 One expects that an asteroid has a small positive charge because of the solar wind. It this is so then a stream of negatively charged paint particles could be projected towards the asteroid. The ultraviolet light from the Sun would melt the paint particles together which would coat the asteroid with a new color.   The new color would be chosen to amplify the Yarkovsky force pushing the asteroid into safe orbit. Professor David Hyland of Texas A&M University has lead a team which has been studying this method of causing an asteroid's orbit to change so that it will miss the Earth. His group is proposing to test these ideas on Apophis. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 242 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

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243-Comet Ahoy


Published PRX April 16, 2016
Recorded April 15, 2016

 All comets are likely to have a small solid icy nucleus the nature of which remains a mystery because it is obscured by the glowing gases which surround it. 

Recently a relatively dim object, Comet P/2016 BA14 flew past Earth at about 9 times the distance to our Moon from us. It was the third closest comet approach in recorded history. This situation allowed NASA scientists to use the Goldstone Solar System Radar located in California to obtain detailed RADAR images. These revealed the nucleus of P/2016 BA14 to be about 3000 feet in diameter. It slowly spins once very 35 to 40 hours as it travels on its 5.26 year orbital path around the Sun. Observations by the NASA Infrared Telescope Facility on Mauna Kea reveal the nucleus to be as dark as fresh asphalt which means it's surface is about 4 times darker than that of our moon.

In the future this comet will make rather close approaches to Earth in 2048 and to Jupiter in 2188. These encounters make P/2016 BA14's orbit unstable in the sense that it is likely to eventually hit Jupiter, Earth or Mars or perhaps even be ejected from the solar system. 

Asteroid hunter's will continue to search for potentially dangerous objects like Comet P/2016 BA14. We don't really know how many more are out there and they are so dim that we can only detect them on their relatively close approaches to planet Earth.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 243 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

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244-Earth's Wobble

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Published PRX April 16, 2016
Recorded April 15, 2016

For those of us in the mid-latitudes the spin of the Earth on its axis carries us along at somewhere between 700 and 900 miles per hour.  We don't feel the motion because its a smooth ride.  Superimposed on this steady motion are wobbles which effect GPS readings and can tell us about changes in ice sheets, water movements, and even climate change.

Recently scientists at NASA's Jet Propulsion Laboratory published a paper which lays out how the movement of the water on Earth effects the Earth's wobbles. For the past 100 years the Earth's spin on its axis, which we call the North pole, has been moving southward towards Hudson Bay at the rate of a few inches per year.  In 2000 the north pole's motion took a sharp turn to the east and accelerated to nearly 7 inches per year in the direction of the British Isles. 

After taking into account the changes in the ice sheets in Greenland and Antartica the NASA JPL researchers were left with an unexplained speedup in the Earth's wobble.  By using data from NASA's GRACE satellite to track changes in gravity over the planet on a month to month basis these researchers were able to pinpoint the cause of the previously unexplained wobble.  To their surprise their data pointed to the drought in India and the Caspian sea area as the driver for the wobble changes they observed. 

Who would have suspected that a careful study of the Earth's motion in space would turn out to be a key to understanding past climate change and enable us to predict future patterns of flooding and drought.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 244 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

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245-Asteroid Awareness

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Published PRX April 21, 2016
Recorded April 20, 2016

Recently in response to a question from a reader of the "Asteroid Day" blog, my Catalina Sky Survey team captain Eric Christensen, wrote a blog piece entitled "Is It Just Me, Or Are Asteroids More Dangerous They Used To Be?".  

In it, Eric points out that astronomers are detecting many more of the asteroids that come near planet Earth than we did in the past.  These discoveries result in many more news stores about asteroids currently being published than what we saw 10 years ago.

Eric also comments on the fact that news, both true and false, spreads rapidly from postings on the internet. For example, in the past few years he cites reports of asteroid impacts which were widely quoted even though the events in question were later discovered to have no relationship to asteroids at all. Unfortunately, these unsubstantiated rumors have influenced people's impressions about the danger posed by objects from space.

Eric concludes his piece with a summary of the tiny but not zero probabilities that space rocks of various sizes will strike and do damage to members of the human race. 

Bottom line is that Earth approaching asteroids are a part of our environment. Their tiny spectacular threat to us is not increasing. The vast majority of asteroid impactors are small and if you are lucky will treat you to a nice light show.  In fact personally, you are more likely to be killed by an earthquake, flood, tornado, car crash, airplane disaster, or a gun than you are by being hit by an object from space. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 245 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


246-Anatomy of an Extinction Crater


Published PRX April 21, 2016
Recorded April 20, 2016

About 66 million years ago a 6 mile diameter asteroid impacted the Earth.  It landed off the coast of the Yucatan Peninsula in Mexico, creating a crater more than a hundred miles in diameter.  This event has been widely accepted as creating a fire storm which was bad news for the Dinosaurs and the other species which went extinct at that time. On the other hand, this impact may have been good news for our mammal ancestors which were able to hide underground, emerge, and flourish in its aftermath.  

In order to investigate the aftermath of the potentially dinosaur killing asteroid impact, researchers are drilling a mile deep core sample into the inner ring of the Chicxulub crater which the impact produced. Their drilling rig sits on legs which lifts it above the waves on the surface of the 56 feet of water covering their target. Once through the 1800 feet of limestone which has been deposited since the event,  the crew will drill day and night extracting 10 foot cores as they go through the more than a half mile of material which is the geological record since impact.   Laying the cores end to end allows the scientists to measure changes in rock layers, microfossils, and DNA as the Earth and its life forms recovered from the asteroid impact.  The 300 foot layer immediately above the rocks forming the peak crater rim is likely to be made up of the ash and other debris which fell out of the atmosphere in the weeks after the impact.  What story will it tell? Stay tuned.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 246 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer



247-Potential Mining Target


Published PRX April 28, 2016
Recorded April 20, 2016

Mining asteroids may be a much cheaper way to get the raw materials that space colonists need when compared to the cost of lugging  supplies up from the surface of our planet. Using the abundant solar energy in space, water ice from asteroids can be turned into hydrogen and oxygen which is ideal rocket fuel.  The metals which many asteroids contain can be turned into the items space explorers need.

Recently my Catalina Sky Survey teammates Greg Leonard and Richard Kowalski found an asteroid which has an orbital period about the Sun of 382 days.  The new space rock was tracked by eleven observatories around the world. These data allowed scientists at the Minor Planet Center to calculate its orbit, estimate its size, and give it the name 2016 GC221.

Greg and Richard's new space rock, 2016 GC221, is about 125 feet in diameter. In the next 50 years this small space rock will make ten approaches to planet Earth. 

It will be interesting to obtain a spectrum of 2016 GC221 so that we will know what it is made of.  It's minimum velocity relative to the Earth is about 5.9 miles per second.  This about 50% faster than we would like since it will take more rocket fuel to rendezvous with it than it would for some of the other asteroids we have found.  If 2016 GC221 happens to contain metals like platinum, nickel, iron, and copper or substantial amounts of water ice I suspect that humans will find a way to get there. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 247 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer



248-Incoming


Published PRX April 28, 2016
Recorded April 20, 2016

Suppose asteroid hunters detect a tiny moving point of light in the night sky which appears to be on a collision course with planet Earth.  The questions which immediately come to mind are what is this object like?  When and where might it impact the surface of our world?  In order to answer these we need data.

To get some practice at responding to an incoming asteroid, researchers trained four telescopes in Hawaii and New Mexico on an object, now called 2016 CG18, which my Catalina Sky Survey teammate Greg Leonard had just found streaking through the night sky.

Because Greg was able to discover this small asteroid before it made its closest approach to us, astronomers at  Apache Point Observatory, NASA's Infrared Telescope Facility, Gemini North, and Magdalena Ridge Observatory were able to track and obtain data on 2016 CG18 as it passed between the Earth and our Moon.

Dr. Nicholas Moskovitz of Lowell Observatory headed up the team that analyzed the data from this coordinated effort.  What this team found is that 2016 CG18 is only about 21 feet in diameter and spins extremely slowly taking about 2 hours to complete one of its complex tumbling motions.

This coordinated research effort has tested rapid response observing protocols which can be used on a difficult fast moving object, like 2008 TC3, which is on a collision course with planet Earth.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 248 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


249-Tough Tourist


Published PRX May 5, 2016
Recorded April 28, 2016

For all but about 2 weeks out of every 46 months , the five hundred foot diameter asteroid which my Catalina Sky Survey teammate, Carson Fuls discovered, remains too faint to detect as it travels about the Sun.

In the 12 days before it made its closest approach to Earth, Carson's new space rock brightened more than one hundred times as it approached us from the direction of the Sun.  After Carson discovered this relatively large space rock streaking away from planet Earth at nearly 18 miles per second, it was observed by telescopes in Arizona, New Zealand, Illinois, and South Africa.  Scientists at the Minor Planet Center were able to use these data to calculate its orbit, estimate its size, and give it the name 2016 GX221.

2016 GX221 must be made of rocky material since at its closest point to the Sun it receives more than one and a half times more energy than what heats the surface of the planet Mercury to a temperature of 800F. It could even be made of a mixture of expensive metals like platinum, gold, silver, and much less rare metals like iron and nickel.

Currently 2016 GX221 is no threat to planet Earth since its orbit never puts it closer than about seven times the Moon's distance from us.  The fact that it can come close to Mercury, Venus, Earth, our Moon, Mars, and Jupiter means that its orbit will be changed by one of these encounters.  It may eventually hit the Sun, a planet, or perhaps be ejected from our solar system.  Only time will tell.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 249 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

250-Born Wild

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Published PRX May 5, 2016
Recorded April 28, 2016

Today our solar system is a pretty calm place. However, meteorites we find on Earth as well as the cratering we observe on our Moon, Mercury, Mars, and other bodies suggest that our solar system was born wild and stayed that way for a while.  There is also the puzzling fact that our sparsely packed inner solar system is very different from the densely packed, close in, planetary systems which have formed about nearby stars.

Dr. Konstantin Batygin of CalTech and Dr. Gregory Laughlin, University of California at Santa Cruz, have published a paper in the Proceedings of the National Academy of Sciences in which they present the results of calculations which simulate how our solar system was formed.  Their work suggests that the giant planet Jupiter migrated from farther out than where it is now to only about one and a half times the Earth's distance from the Sun.  In the process Jupiter's gravity spun most of the tightly clustered inner massive planets into our Sun.  Later under the influence of the newly formed planet Saturn, Jupiter was drawn back to about five times the Earth's distance from the Sun where we find it today.  The material Jupiter left behind in the inner solar then formed into the small rocky worlds Mercury, Venus, Earth, and Mars. 

Take time to look up the current positions of Jupiter and Saturn on the web. They are bright enough to be seen even from within a light polluted city.  As you gaze at these distant gas giants you might say thank you for the part they played in to producing the place where you are standing today.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 250 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

251-Fresh Lunar Craters


Published PRX May 12, 2016
Recorded April 29, 2016

Without an atmosphere and running water, craters formed on the Moon remain visible for eons.  They are interesting targets for Earth bound observers with small telescopes to explore and photograph. 

Not all of the Moon's craters are old.   Amateur and professional observatories routinely monitor the moon to detect some of the bright flashes which occur. Since 2006 the NASA Lunar Monitoring program has recorded more than 300 flashes created by meteor impacts on our Moon. The brightest so far was on March 17, 2013.   Dr. Mark Robinson of Arizona State University headed up a team which analyzed recent data from the NASA Lunar Reconnaissance Orbiter.  This team of researchers were able to spot the 62 foot diameter crater which was created by the impact that produced the March 2013 flash. They were also able to identify more than 200 lunar surface changes, out to almost 19 miles from the impact crater, which were caused by this event.  This group of scientists were also able to verify that the impact of micrometeorites has modified the lunar soil to a depth of several feet or more.

Fresh craters on the Moon tell us about the number and the size distribution of objects which enter the Earth-Moon system.  Current estimates suggest there are 24 craters larger than 60 feet in diameter which are produced on our Moon each year.  Structures for lunar colonists and lunar experiments need to protect them from these as well the many many more BB sized or smaller objects which arrive at gun shot speeds from all directions in space. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 251 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


252-The King


Published PRX May 12, 2016
Recorded April 29, 2016

The planet Jupiter is so bright that you can even spot it under the artificial light dome of one of our cities.  Jupiter has a mass of more than 300 times that of the Earth and contains more than twice the mass of all of the other planets, dwarf planets, asteroids, and comets in our solar system combined. 

Jupiter has had an enormous influence on the evolution of our solar system.  It appears to have cleared out the inner solar system leaving enough rocky debris to form Mercury, Venus, Earth, and Mars.  Without this action our solar system is likely to have turned out like the more than half of the planetary systems which we have found.  These distant solar systems consist of non-inhabitable super Earth sized planets orbiting closely about their host stars.

In terms of the defense of planet Earth from impacting objects, Jupiter is a mixed blessing. It apparently deflects some of the long period comets out of Earth impacting orbits while sending some asteroids and comets our way.  In 1770 a small comet came in from the outer solar system and passed near Jupiter.  This encounter sent it straight towards Earth.  Fortunately the King's aim wasn't perfect and this celestial visitor missed humanity by about a million miles.  After two orbits of the Sun this comet once again passed near Jupiter.  This time the King ejected it into interstellar space.

Look up where to find Jupiter on the internet and observe it. Jupiter is an awesome sight in binoculars or a small telescope.  As you view this gas giant contemplate the fact that it is likely the reason you have a place to stand and air to breathe.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 252 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


253-Lunar Village


PRX May 19, 2016
Recorded April 29, 2016

Covered by a blanket of lunar soil to protect it from BB sized meteoroids arriving a gunshot speeds, a village is nestled in a large crater on our moon.  The individual structures are connected together by tunnels.  The site was chosen to access the water and metals which were brought to the site by asteroid impacts.

The village will use the raw materials found near the site and abundant solar energy to enable massive 3D printers to create facilities for humans from around the world to live and work on our moon.  This outpost will be the beginning of a path from the current International Space Station to Mars and beyond. 

NASA's Orion Crew and the European Service modules are the critical first steps in enabling humans to move beyond low Earth orbit.  To build on these efforts representatives from more than 14 countries around the world are coming together for an International Symposium on Moon 2020 to 2030. The primary goals of this symposium are to create a structure to which will be built on partnerships between governments, academic institutions, and other private sector groups.  This organization will enable the world wide spacefaring community to move from individual missions to an architecture which will enable repeated missions of increasing levels of accomplishment.  This new collaboration will encompass both automated missions as well as ones which involve the cooperation of humans and robots. 

The next decade is shaping up to be very interesting in the continuing saga of space exploration.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 253 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer



254-Blinded


PRX May 19, 2016
Recorded April 29, 2016

Blinded by inappropriate outdoor night lighting, much of humanity is now unaware of the rich beauty of the Universe which surrounds them. To see sights which have inspired countless generations of lovers, poets, scientists, authors, artists, mathematicians, and dreamers people must travel out of their artificial light domes to one of the few remote locations which offer the opportunity to view the natural night sky.

The International Dark Sky Association, also known as the IDA, exists to identify and help protect your opportunity to become personally connected to the mysteries of the natural night sky. You can explore one of these natural night sky sites remotely at cosmiccampground.org. Don't stop there. Visit a dark sky site which you can locate on the darksky.org website.

Pick a nice clear night when it is not too cold.  Take your inner child and perhaps a young person with you.  A flashlight with a red wrapper attached to it with a rubber band is essential.  Don't look at a white light for at least 30 minutes. Bring a star chart to make friends with some of the bright stars. Your dark adapted eyes, binoculars, and/or a telescope will put you in direct personal contact with the wonders of the natural night sky. Views of the  Milky Way, star clusters, faint galaxies, the zodiacal light, and other treats are bound to be good for your soul.

Pass your experience on by telling others about what it is like to view the natural night sky.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 254 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

255-Earth Venus Express

Published PRX May 26, 2016
Recorded May 22, 2016

We will probably never know the details of the collision that put my Catalina Sky Survey teammate Carson Fuls'  recent discovery, 2016 HD3, on its current path.  What we do know is that Carson's new space rock is about 25 feet in diameter and in the next 100 years will make 53 close approaches to planet Earth and 12 to our sister planet Venus.   In 2016 this small object passed to near both the Earth and our Moon.  It's 322 day orbit around the Sun can someday bring it to about a quarter of the Moon's distance from where we live.

The fact that Carson was able discover this small asteroid 4 days before it made its closest approach to us means that if it had been an impactor we could have let people know well in advance. Not that 2016 HD3 would have posed much danger since one this size enters the Earth's atmosphere every 5 years or so producing a light show at an altitude about three times higher than airliners fly.  If you are lucky you will witness such an event and perhaps even be able to pick up a small piece of it that is able to reach the ground.  Such meteorite contains a record of collisions which it has had going all the way back to the formation of our solar system. Even if you don't see a meteorite fall, with diligence,  you can find one with your eye, a powerful magnet and/or perhaps a metal detector.    In some cases your discovery could be worth more than its weight in gold and diamonds. In any case, being able to hold an object from space will make your effort rewarding.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 255 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

256-Pale Blue Dot 


To be Published PRX May 26, 2016
Recorded May 22, 2016

More than 25 years ago Voyager 1 took a picture of the Earth from beyond Pluto's orbit. This image shows our home planet to be an isolated tiny pale blue dot floating in the vastness of space.  

Dr. Carl Sagan used this photograph in the title of his 1994 book "Pale Blue Dot: A Vision of Human Future in Space".  His description of this image and how it demonstrates our fragile unique place in the cosmos is still valid today.

The next generation of space and ground based telescopes will be able to identify the pale blue dots among the thousands of planets that we have discovered to be orbiting distant stars.  These discoveries will inspire humans to discover methods to identify those worlds on which they could live and prosper.
 
Recently a team of scientists published a paper in the Astrophysical Journal in which they investigated the degree to which the color of a planet can be used to measure its potential as an abode for life.  They found that the light reflected by the Earth from the ultraviolet to the near infrared has a  unique "U" like shape.  Further, there are subtile differences between the light reflected by the Earth and the light reflected by hypothetical uninhabitable bluish planets which are in reality frozen lifeless worlds with thick atmospheres. They could not completely rule out the possibility of uninhabitable blueish imposters.  Very large telescopes will be necessary to obtain the spectra which will allow humans to discover worlds which have oxygen rich atmospheres and the other molecules which could only be there as a result of the chemistry of life. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 256 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

257-Raw Asteroid


Published PRX June 2, 2016
Recorded May 22, 2016

Most asteroids that we observe have been baked by the Sun for billions of years. As a result, any ices or frozen gases that they may have once possessed are long gone.  Comets on the other hand have spent so much time far from the Sun that they still contain volatile materials. As a typical comet approaches the Sun, the frozen gases and ices it contains evaporate to form a beautiful coma and a long tail.

Recently the Pan-STARRS group in Hawaii discovered a weakly active comet with a very short tail. Dr. Karen Meech of the University of Hawaii's Institute of Astronomy headed up a team which analyzed the data obtained from observations by the European Southern Observatory Very Large Telescope in Chile and the Canadian-French-Hawaii telescope on Mauna Kea.   Their results suggest that, this comet, C/2014 S3 (PANSTARRS) is a ancient rocky body which was formed about the same time as the Earth.  A relatively short time after formation it was ejected from the inner solar system. It took up residence in the Oort cloud far from the Sun where it remained until fairly recently. Dr. Meech concludes “We already knew of many asteroids, but they have all been baked by billions of years near the Sun. This one is the first uncooked asteroid we could observe: it has been preserved in the best freezer there is.”

Astronomers will now be on the look out for other objects like this one to provide important insights into the origin and formation of our solar system.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 257 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

258-Odds of Aliens

Published PRX June 2, 2016
Recorded May 22, 2016

Recently Dr. Adam Frank of the University of Rochester and Dr Woodruff Sullivan of the University of Washington published a paper in which they addressed the question  "What are the odds that humans are the only technological species that has ever arisen in a given volume of space?

These researcher's calculations indicate that we are likely to be the first advanced civilization in a cube 1000 light years on a side centered on our Sun.  However, they show that even if the if the odds of a planet developing a technological society are as low as your chances of winning the power ball there are likely to be hundreds of civilizations in the Milky Way and millions of civilizations in the observable Universe.  The Frank and Sullivan results thus strongly suggest we are not unique and alone in the Universe. 

Humans are on their way to making permanent changes to our planet's climate which may eventually  spell the end to our current level of technology.  Do typical civilizations that arise in the Milky Way only last a few centuries after achieving high tech mode? If that is true then those intelligent societies that have formed are already gone and no more will develop before the end of our civilization.

Humans continue to look into the night sky and wonder what is out there.  The immense distances and the uncertain lifetime of an advanced civilization make it seem unlikely that we will discover intelligent beings outside of Earth.  However, I remain hopeful of one day waking to the news that we have received signals from thinking beings which live elsewhere in the Milky Way.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 258 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


259-Trans-Neptunian


Published PRX June 9, 2016
Recorded May 30, 2016

During the course of a single night our telescopes can find more than 10,000 moving objects. Fortunately our software geniuses are able to sort through this pile to allow us to focus on unknown objects which require additional observations. Most of the time asteroid hunters are able to decide if an unknown moving object is an Earth approaching asteroid by observing it for a few nights to determine it's path around the Sun. However, recently my Catalina Sky Survey teammates Alex Gibbs, Greg Leonard, Carson Fuls, and Richard Kowalski as well as observers in Hawaii, New Mexico, Australia, and Kitt Peak in Arizona had to follow an unknown object for nearly a month to determine its nature.

The new object they discovered is now called 2016 EJ203.  It is about 3000 feet in diameter and takes 504 years to orbit the Sun on a path which goes from between Mars and Jupiter out to 3 times Pluto's distance from the Sun. In 2016 humans were able to spot 2016 EJ203 during the two weeks every 500 years that it is bright enough for us to detect.  The Minor planet Center has classified 2016 EJ203 as a Trans-Neptunian object.   Our catalog of these distant places now has several hundred entries ranging in size  from Pluto and 4 other large dwarf planets to small objects like 2016 EJ203.

This object may be the nucleus of a burned out comet or a fragment left over from the formation of the solar system. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 259 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


260-Gliding to Space

Published PRX June 9, 2016
Recorded May 30, 2016

About 20 years ago Dr. Elizabeth Austin began to investigate Polar Vortex winds during the long winter nights near the poles. One of its components, the stratospheric polar night jet, can create 300 mph winds which in turn can project atmospheric mountain waves as high as 130,000 feet into the stratosphere.  

The Airbus Perlan II is an engineless glider designed to surf stratospheric mountain waves in our atmosphere to the edge of space. Cruising at 400 mph at an altitude of 90,000 feet this glider with a wing span of 85 feet will become the highest level flying winged vehicle in history and will be able to travel above 98% of the Earth's atmosphere.  The cabin of Perlan II is pressurized and is occupied by a crew of two who make their high altitude flights from a base in Argentina. 

The Perlan II will carry a package of scientific instruments which will enable it to study the atmosphere without the presence of a polluting engine to bias the measurements.  The results will provide important information about our atmosphere which will help humans to adapt to the climate change we have created.

At the highest point of its flight  Perlan II will be flying in an atmosphere similar to what exists on the planet Mars.

In the future high flying commercial aircraft in our atmosphere as well as vehicles which will enable us to explore our neighbor Mars will benefit from the data obtained by the Airbus Perlan II.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 260 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


261-Cool Star Homes


Published PRX June 16, 2016
Recorded May 30, 2016

Recently Dr. Michael Gillon of the University of Liege in Belgium and a team of astronomers hypothesized since that approximately 2/3 of the stars in our neighborhood are red dwarf stars some of them might host inhabitable planets.  To test this idea the researchers began to carefully monitor some nearby red dwarfs with a robotic telescope in Chile to see if any of them the have regular dips in brightness which indicate the presence of planets orbiting them.

This team of astronomers were delighted when a faint star in an infrared star catalogue showed regular dips in brightness indicating the presence of three planets.  Followup observations by the European Southern Observatories' 8 meter telescope in Chile confirmed the presence of three Earth sized planets orbiting a star now known as TRAPPIST-1.  This extremely faint red star is only slightly larger than the planet Jupiter and puts out 0.05% of the energy of our Sun.  Two of its Earth sized planets orbit every 1.5 and 2.4 days receiving four and two times the radiation the Earth receives from our Sun. They are probably two hot to be habitable.  The third Earth sized planet orbits farther away and thus might have life permitting temperatures on its surface.

The discovery of three Earth sized planets orbiting the extremely, cool, faint red dwarf star TRAPPIST-1 suggests the possibility of the presence of many more relatively nearby Earth like planets.  The next generation of ground and space based telescopes will tell us about their surface conditions.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 261 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


262-Shooting Star's Daddy

Published PRX June 16, 2016
Recorded May 30, 2016

Every year before Christmas the Geminid meteor shower treats us to a fast, bright, and reliable light show which occurs when the Earth passes through a stream of dust and small rocks orbiting the Sun. Now we are able to pinpoint the source of these shooting stars which to us appear to come from the constellation of Gemini.

Every 523 days the 3 mile in diameter Earth approaching asteroid Phaethon is closest to the Sun.  At this point in its orbit it receives nearly eight times the dose of solar radiation that heats the surface of the planet Mercury to 800 degrees Fahrenheit.  To find out what such an encounter does to Phaethon, NASA astronomers observed it with the twin STEREO spacecraft when it was only 15 solar diameters from the Sun's surface. To their surprise Phaethon suddenly got twice as bright indicating that it likely to have burped out a cloud of dust and gravel which in turn reflected more sunlight in our direction.   

The path of the meteoroids which create Geminid shooting stars confirm that were ejected from the asteroid Phaethon when it made close approaches to the Sun.  Without this source of replenishment this material would have long ago been depleted by the Earth's gravity. Take  time to enjoy these gifts of the asteroid Phaethon by going to place far from city lights in mid-December.

In 2017 this strange little asteroid Phaethon will approach to within about 27 times the Moon's distance from us and will be the subject of intense study by humans.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 262 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


263-Catching Shadows

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To be Published PRX June 23, 2016
Recorded June 13, 2016

For years humans knew Pluto, the first Trans-Neptunian object to be discovered, only as a moving point of light in the night sky. It wasn't until 58 years after it's discovery that astronomers were able to observe a star as Pluto passed in front of it. These data gave an accurate diameter and also proved that Pluto has an atmosphere.   There are estimated to be 100,000 Trans-Neptunian bodies larger than 60 miles or so in diameter. They have stories to tell about the beginning of the solar system. Additionally, sometimes, a passing star changes one of their orbits sending it into the inner solar system and perhaps near to us.

The size and shape of a Trans-Neptunian can be found by measuring the size of the shadow it creates as it passes in front of a star. Because it is not known in advance exactly where such a shadow will be located on planet Earth, it is necessary to have a wide net to catch it.  

To answer this need, a network of 56 stations each equipped with a telescope, camera, and timing device will allow the operators to measure a star's brightness as a Trans-Neptunian object passes in front of it. These science teams have been established primarily at schools usually at the 9-12 grade level. These are spaced more or less evenly along a path through the western states that goes from Canada to Mexico.  

In the process of measuring the sizes and shapes of distant members of the solar system the students and teachers working together on this project will have the exciting opportunity to be a part of an authentic scientific investigation.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 263 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer

More Information On This Program

264-Tough Guy


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To be Published PRX June 23, 2016
Recorded June 13, 2016

Many of the Earth approaching asteroids that we discover are loose collections of rocks and dust held together by their tiny gravity.  If such a rubble pile passes near the Sun, the strong heating it experiences, can cause it to shed a trail of debris behind it.  If the Earth runs into such a debris trail we are treated to a meteor shower.  An example of this is the Earth approaching asteroid Phaethon which apparently is the source of the spectacular mid-December Geminid meteor shower.

Recently my Catalina Sky Survey team captain Eric Christensen discovered a 1000 foot diameter potentially hazardous asteroid now called 2016 LV47.  It orbits the Sun once every 2.29 years on a path that takes it from 64% of Mercury's distance from the Sun out to between Mars and Jupiter.  When it is closest to the Sun it zips along at 51 miles/second and receives nearly 4 times the amount of energy which heats the surface of the planet Mercury to 800 F.  The fact that it survives this experience suggests that it may be a solid metallic/rocky asteroid. 

An asteroid the size of 2016 LV47 strikes the Earth every 80,000 years or so making a crater more than 3 miles in diameter as it releases the energy of several thousand million tons of TNT.  Not to worry 2016 LV47 never gets closer than about 13 times the Moon's distance from us.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 264 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


265-Dancing with Earth


Published PRX June 30, 2016
Recorded June 28, 2016

The Moon is the Earth's long time dancing partner.  This unequal pair revolve about a teeter totter type balance point which in turn orbits the Sun every 365 and a quarter days.

Sometimes the Earth-Moon dance is joined by smaller objects.  In 2003 the LINEAR program, located at White Sands Missile Range in New Mexico, discovered a 65 foot diameter object which never got further than about a tenth of distance to the Sun from us for nearly 10 years.  It has since left our neighborhood.  Recently, the Pan-STARRS group in Hawaii discovered a 185 foot diameter asteroid which has been the Earth's dance partner for almost a century and is likely to continue to be our companion for several more centuries.  The new object, 2016 HO3, takes only 16 hours and 11 minutes longer to orbit the Sun than does the Earth itself.  About half the time 2016 HO3 is closer to the Sun than we are, moves faster, and passes the Earth while the rest of the time it is further away from the Sun, moves slower than we do, and we pass it.  The Earth's gravitational pull keeps it from straying neither closer than 38 times or farther than 100 times the Moon's distance from us. In this way, 2016 HO3  circles our home planet in a donut shaped pattern which travels with us on our yearly trip around the Sun.

Perhaps 2016 HO3 is an asteroid that humans would like to visit. Further research will reveal its size, shape, rate of spin, and chemical composition. Maybe then we can start selling tickets.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 265 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


266-Colliding Planets

Published PRX June 30, 2016
Recorded June 28, 2016

In 1950 Immanuel Velikovsky published a book "Worlds In Collision" in which he drew from mythologies and religions around the world to describe a very catastrophic but not scientifically valid version of our solar system's history.  

Today scientists are replacing myths with solid evidence that violent impacts between planets, planetesimals, asteroids, and comets are very common in our galaxy.  They play a vital role in the formation of solar systems which contain habitable planets. 

Dr. Elisa Quintana a NASA Ames Research Center and SETI Institute Research scientist recently published a paper in the Astrophysical Journal in which she describes the results of her computer models of space collisions and their role in producing our solar system as well as those we observe to surround other stars.  

Most of what we find important for Earth to harbor life: it's spin rate, rotation, and thus it's weather; its water and atmosphere; its core and mantle; and many other properties have been shaped by impacts and collisions.  To test how these important properties of Earth came about Dr. Quintana ran two-billion year computer simulations which followed the development of a proto-planetary disk to a mature solar system like oursIn 280 such simulations, her computer calculations typically produced the presence of 3 or 4 rocky inner planets.  Interestingly, more than half of her simulated solar systems contained at least one Earth-like planet.    Videos made from Dr. Quintana's calculations will give you a new appreciation of where you live.
  
For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 266 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


267-Hiding From ET


Published PRX July 7, 2016
Recorded June 28, 2016

It is unlikely that ET will discover humans by receiving the TV signals from "I Love Lucy" which are now 65 light years from Earth and are spreading into space at the speed of light, since recent scientific calculations indicate that we are probably alone in a 1000 light year cube centered on the Sun.  However, the same analysis suggests that there may be several hundred advanced civilizations elsewhere in the Milky Way.  Should mankind look forward to making contact with one of them? Some scientists like Stephen Hawking and others who have thought about human-alien contact and say maybe not.  They are concerned that human-alien contact might turn out for mankind to be like what the residents of the Americas received from the invading Europeans.  This  unhappy prospect has prompted a discussion about the wisdom of humanity hiding from ET and/or ET hiding from us.  

So far the NASA Kepler spacecraft has discovered more than 4,500 planets orbiting distant stars by measuring the tiny dip in the host stars brightness as one of it's planet's pass in front of it. Undoubtedly ET is aware of this process and may be hiding from us by shining a powerful laser in the right direction to mask the tiny dip in their Sun's brightness as their planet passes in front of their host star.  A tunable, programmable laser could create an effective mask which would frustrate attempts to discover a planet. We could hide Earth from discovery in this way by using the power generated from 100 wind turbines.  On the other hand humans could announce their presence to the Milky Way by using such a system for signaling instead of hiding.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 267 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


268-Mars Weather Report

Published PRX July 7, 2016
Recorded June 28, 2016

Before you pack your bags for a trip to Mars you will want to check out the weather data that NASA's Curiosity Mars Rover has recorded over the past two Martian years.

Prepare yourself for wide swings in temperature. On a warm summer day, Curiosity recorded a high temperature of 60.5 degrees Fahrenheit, however, at night even during the warmest part of the Martian year the temperature can fall to 130 degrees below zero F.  During the Martian winter it is really cold.  The extreme low temperature recorded by Curiosity in the Gale crater is minus 148 degrees Fahrenheit. 

Mars is extremely dry.  Its atmosphere contains a thousand to ten thousand times less water than what we experience on planet Earth.  Even so the Martian relative humidity has been measured to be as high as 70% during the winter.  So far Curiosity has not spotted any frost accumulating on the ground.

An extreme aspect of the Martian year is the capture and release of carbon dioxide at the poles causing it's atmospheric pressure to vary by 25% or so.  

Keep your eye on the Martian Weather Channel. Global dust storms often hide surface features for days or weeks.  Martian storms can be exciting but in reality pack little destructive force. For example, in the thin Martian atmosphere a wind of 150 miles per hour would not straighten out an American flag.  However, be ready for  dust devils 19 miles which are high crackling with lightning.  

There is no getting around the fact that you will need a space suit and long woolies to survive on Mars.

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 268 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


269-Gamma Ray Eyes


Published PRX July 14, 2016
Recorded June 29, 2016

If you woke up tomorrow with gamma ray eyes things would look very different.  Geology would come to life as you peered into the Earth and became aware of the various minerals it contains.  Gamma rays coming from stars, supernovae, pulsars, and black holes would create a fog extending over all of the sky.

Perhaps the strangest sight of all to your gamma ray eyes would be the Milky Way. Amazingly, your view our galaxy would be dominated by two giant bubble like structures which are invisible to real human eyes. These bubbles of gamma ray emission have a diameter a quarter of the size of the Milky Way's disk and stretch across about half of the sky. Imagine a view of the Milky way the size of a DVD disk with tangerine sized bubbles of gamma ray emission touching each side of its central hole.

By viewing a distant quasar through the one of the giant bubbles, the Hubble Space telescope was able to measure the speed and composition of the two million mile per hour wind which is pushing the bubbles into intergalactic space.  The silicon, carbon, and aluminum atoms the HST detected were created inside of massive ancient stars near the galactic center. 

Astronomers think that these bubbles were created by either an incredible burst of star formation or a major burp from a supermassive black hole at the center of the Milky Way.  Unlike many of the events in the Universe which occurred in the distant past these bubbles were created only about 2 million years ago at about the time our ancestors were learning how to walk upright on planet Earth. 

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 269 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer


270-Space Opals

Published PRX July 14, 2016
Recorded June 29, 2016

Opal, the national gemstone of Australia,  is silica, the most common ingredient of sand, with a number of water molecules attached to it.  On Earth Opal forms when water evaporates from a slurry of sand and water which is deposited repeatedly in a crack or fissure in a rock over a long period of time.   The resulting opal may contain from 3 to 21% water by weight.

Professor Hilary Downes of Birkbeck College London headed up a team which discovered Opal in a meteorite which was found in Antartica.  Previous to their work the only known extra-terrestrial Opal consisted of a few crystals which were found in a meteorite from Mars. 

The Antarctic meteorite that Professor Downes and her team studied, EET 83309, is made up of thousands of small pieces of rocks and minerals. This space rock was created by collisions between objects from various parts of our solar system.  Some of them are likely to have been carrying large amounts of water ice. The Downes team found solid evidence that the opal was formed before their sample left the surface of the parent asteroid, traveled through space, and was recovered by humans on the Antarctic ice sheet. 

Professor Downes concludes  "This is more evidence that meteorites and asteroids can carry large amounts of water ice. Although we rightly worry about the consequences of the impact of large asteroids, billions of years ago they may have brought the water to the Earth and helped it become the world teeming with life that we live in today."

For Travelers in the Night this is Dr. Al Grauer.

Go to travelersinthenight.org program 270 for more information.

© 2016 A. D. Grauer and ℗ 2016 A. D. Grauer





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