Programs 31-60

Travelers in The Night

Programs

31-A Gentle Breakup Of An Asteroid


Published PRX April 3, 2014
Recorded March 21, 2014
remixed July 15, 2014


Newton formulated that the change in motion for an object depends on the amount of force and the length of time it is applied. For this reason a baseball pitcher tries to have a long pull on the ball before releasing it.

Astronomers have a theory, called the Yorp effect, that light from the Sun produces a very tiny torque which increases the rate of spin of an object. The effect is so small that it would take billions of years to be produce a measurable outcome. How can such an idea ever be tested?

In September of 2013, the Pan-STARRS group found a strange moving object in the night sky. The plot thickened when the Keck Telescope on Mauna Kea Hawaii found that instead of being a single body it appeared to be three small objects embedded in a cloud of gas and dust several thousands of miles in diameter. The Hubble Space Telescope was used to see what is going on.

Hubble found that this object changes significantly over a period of months, that it has 6 tails, and that pieces of it continue to emerge from the center and slowly move away at a walking pace.

An asteroid collision is too violent to cause what is seen. The object is too cold for expanding gases to cause it to break up. The best explanation which fits the data is that Sun light has slowly, over billions of years, increased P/2013 P5's rate of spin causing it to gently come apart. Some of the dust and small particles which escape from it will orbit the Sun. When the Earth runs into them we may see them as meteors in our night sky.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer



More Information On The Break Up Of An Asteroid


32-A Peanut Shaped Asteroid with a Moon


Published PRX April 3, 2014
Recorded March 29, 2014
remixed July 15, 2014

It appears that Hektor and its moon were created by a collision between two icy asteroids early in the 4.5 billion year history of our solar system when things were more chaotic. They happened to land in a gravitational dip which has allowed them to remain relatively undisturbed for billions of years.

The asteroid Hektor orbits the Sun at a point where the gravity of the Sun and Jupiter create a stable point 60 degrees in front of the giant planet. In 1907 Hector was discovered as a moving point of light in the night sky. For the next 99 years its true nature remained unknown. In the past few years the Keck Telescope in Hawaii has discovered that the main body is a 230 mile long peanut shaped object. Most recently Keck was used to discover that Hektor has a 7.5 mile diameter moon which has a dense core surrounded by icy layers. This asteroid moon orbits the peanut shaped Hektor in a stable orbit every 3 hours.

Recently, NASA scientists using the Goldstone Radar telescope were taking advantage of a close approach of a potentially hazardous asteroid to obtain radar images. These data show 2006 DP14 is a peanut shaped object about 1300 feet long. It slowly spins with a 6 hour period. Previous data from Goldstone and the Arecibo Observatory in Puerto Rico suggests that more than 10 % of near Earth asteroids larger than 650 feet in diameter have a peanut shape. This knowledge will be important if we find one of these strange objects is on a collision course with our planet.


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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer




33-A Busy Month in the Earth's Neighborhood


Published PRX April 10, 2014
Recorded April 10, 2014
remixed July 15, 2014

For us who look for Earth approaching objects, March of 2014 was a busy month. Six asteroids which pass closer than our Moon were discovered and tracked. The smallest of them is the size of an SUV and the largest would fill an NBA basketball court. Fortunately none of them were on a collision course with Planet Earth.

Interest in smaller space rocks has increased since a semitrailer truck sized asteroid entered the Earth's atmosphere over Russia in February of 2013. Most of the nearly 1500 injuries could have been avoided if people in the impact area had been warned to stay away from windows.

In January of 2014 a refrigerator sized asteroid was discovered about 20 hours before it exploded over the Atlantic Ocean off the coast of Africa. It is estimated that there are a billion near Earth Asteroids of similar size.

It is likely that we have discovered 90% of the approximately one thousand near Earth asteroids whose impact would cause global climate change. There are probably 300,000 smaller Earth approaching asteroids whose impact would devastate thousands of square miles of the Earth's surface. So far we have discovered about 5,000 of them. There are many millions of space rocks which could cause window breaking sonic booms. Happily we have not discovered any of these objects which will impact the Earth any time soon.

An Asteroid impact is a natural disaster whose effect we have the ability to minimize . The NASA Near Earth Object Program's goal is provide the early detection essential to mitigate such an event.

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

Go to travelersinthenight.org for more information.
© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

34- Number 5000


Published PRX April 10, 2014
Recorded April 10, 2014
remixed July 15, 2014


The 5000th Earth approaching asteroid discovered by the University of Arizona's NASA funded Catalina Sky Survey was found early in 2014. It is approximately 3 times the size of the one which injured 1491 people in Russia in February of 2013. It was discovered by my teammate Jess Johnson. Happily, its closest approach to Earth is slightly farther than our moon.

The other 4999 asteroids discovered since 2003 consist of:
> 141 that are large enough to cause global climate change,
> 1892 that are large enough to
devastate thousands of square miles of the Earth's Surface, and
> 2966 that upon entering our atmosphere would create
window shattering sonic booms.

Fortunately none of these objects will impact the Earth anytime soon.

Our team operates two telescopes, 24 nights per month in the Catalina Mountains near Tucson, Arizona. This effort has discovered 47% of the near Earth Asteroids known to exist. We are part of the NASA near Earth Object Program who goal is to provide the early warning time which is essential to mitigate the effects of an asteroid impact.

Fortunately large asteroids which impact the Earth are extremely rare. Small asteroids are the most numerous and thus mostly likely to present a problem. In the future we hope to have the equipment in place to obtain a heads up if a small asteroid is likely to be an impactor. Then people that are in a potentially effected area will be warned to seek shelter in a manner similar to a tornado warning.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


More on the 5000th Asteroid


35-An Asteroid With A Ring

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Published PRX April 18, 2014
Recorded April 12, 2014
remixed July 15, 2014

Saturn had a strange appearance in Galileo's telescope. At first he described it as being a composite of three objects. A few years later, better telescopes showed a beautiful ring system surrounding Saturn. For more than 350 years Saturn was the only known planet with rings. Now we are aware that Uranus, Jupiter, and Neptune also have ring systems.


Chariklo (“KAReekloe”) is an asteroid which orbits the Sun between Saturn and Uranus every 63 years. It was discovered in 1997 by James Scotti an astronomer with Spacewatch on Kitt Peak in Arizona.


At eight different observatories in Brazil, Argentina, Uruguay, and Chile , in June of 2013, Astronomers were timing the dip in light when the asteroid Chariklo (“KAReekloe”) passed in front of a star. They sought to obtain a better value for its 140 mile diameter. To their amazement they also obtained dips in light before and after the main body passed in front of the star. These extra dips were caused by two narrow icy rings 4 and 2 miles wide respectively. These orbiting rings are separated by a 5 mile wide gap.

A careful study of Saturn's rings has shown that some of them are shaped and maintained by its moons. Neptune's rings are kept sharp by some of its moons. This implies that the asteroid Chariklo (“KAReekloe”) has undiscovered moons which have sculptured its rings.

A number of asteroids have been observed as they pass in front of a star. Chariklo (“KAReekloe”) is the first to show a ring system. Perhaps there are others.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer



36- Earth and Moon as Evening Stars

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Published PRX April 18, 2014
Recorded April 12, 2014
remixed July 15, 2014


From our moving platform on Earth we see the bright planet Venus either as a morning or evening star. This happens because the planet Venus is on an orbit closer to the Sun than ours. This geometry means that Venus never gets farther than 47 degrees from the Sun in our sky.

The Earth is the brightest object in the Martian sky. Observers on Mars see our Earth and Moon as either a double morning or evening star because Mars is further from the Sun than our planet. Recently the NASA Curiosity Rover took a mind expanding image of our Earth and Moon from Mars. Take time to look at this image and ponder the fact that all of the human race is on that bright dot and that the furthest we have traveled in space is between those two points of light.

A human with normal vision standing on Mars would see the Earth and our Moon as a double evening star. An observer on Mars would also see the distance between the Earth and Moon change as they revolve around a common center of gravity.

Perhaps one day humans will set up a base on the red planet and will be able to view this beautiful celestial display.

At this point we do not know if life ever existed on Mars. We do know that liquid water has existed there in the past. Mars has a surface area about the size of the dry land on Earth. Our robotic emissaries are currently exploring Mars. You can participate in the discovery process using the NASA Curiosity Rover website via the internet. Try it. It is truly a reality based imagination stimulating experience.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer





37-Slow Movers At The Edge of Our Solar System

Published PRX April 24, 2014
Recorded April 24, 2014
remixed July 15, 2014

Imagine a world that is so far from our Sun that it receives less than 1/5000 of the heat and light that makes our life possible. If your were standing on it,  you could cover the Sun with the tip of a ball point pen held at arms length.

Going out from our Sun in our Solar System, first we find the rocky planets like Earth,  then the gas giant planets including Jupiter, and finally the Kuiper belt objects with Pluto its most famous example . Beyond that, Astronomers have envisioned a region called the Oort Cloud which is the likely source of an occasional comet. 

Recently Astronomers Dr. Trujillo and Dr. Sheppard used observations made in 2012 and 2013 to identify a 250 mile diameter slow moving object. At its closest approach to the Sun is twice as far as Pluto.  It is so distant that it takes 4313 Earth years to make one trip around the Sun.  Dr. Mike Brown found the first object in what was  thought to be an empty region between the Kuiper belt and the Oort cloud in 2004.  He named it Sedna after the Inuit goddess who created the sea creatures of the Arctic.  At -400 Fahrenheit it has an extremely cold surface. Sedna is approximately 600 miles in diameter and orbits the Sun in a very elliptical path every 11,400 years.

How many icy objects like these two exist and where they come from remain open questions. A tantalizing computer simulation hints at the existence of a dim unseen planet having the mass of 5 Earths located 23 billion miles from the Sun. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


38-The Big Ones

Published PRX April 24, 2014
Recorded April 24, 2014 

One million human lifetimes ago an asteroid impact was at least partially responsible for eliminating the dinosaurs.  This event has allowed our race to evolve to its present state.

A 1km diameter asteroid is 3 times the length of USS Enterprise aircraft carrier.  If an asteroid this size or larger were to enter the Earth's atmosphere, it is likely to be traveling at more than 25,000 miles per hour, and would probably trigger global climate change.

Recently I discovered 2014 GM1. It is the second Km sized near Earth asteroid to be identified in 2014. I found it while observing with the NASA funded Catalina Sky Survey telescope on Mt. Lemmon in Arizona. Fortunately it never comes closer to the Earth than about 22 million miles as it orbits the Sun on a path from closer than Mars to 3/4 of the way to Jupiter.   

2014 GM1 is  number 862 in the list 1 KM or larger Earth approaching asteroids which have been discovered. Statistical analysis suggests that there are about 1000 of these objects. The asteroid hunters have thus fulfilled the Congressional mandate to discover 90% of these large asteroids.

Those of us in the asteroid hunting community are also looking for the near Earth asteroids whose impact would leave a hurricane sized foot print on the Earth's surface or produce a mega tsunami if it landed in the Ocean.  We are searching the skies  to provide the warning time necessary to mitigate the effects of an asteroid impact.     

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


39-Dash Cams and the Anatomy of An Airburst

Published PRX May1, 2014
Recorded April 27, 2014 

Aleksei Dozorov, a motorist in Russia stated “You can get into your car without your pants on, but never get into a car without a dash cam,” .  This attitude is caused by poor highway law enforcement.  It is why many motorists around the Russian city of Chelyabinsk [Chel ya binsk] were able to capture images of a huge meteor flying through the sky.  This unexpected data source has enabled scientists to understand an event which injured 1491 people on February 15, 2013 . 

Additional  data came from an array of infrasound detectors around the world.  The measurements they made were calibrated by the nuclear test explosions done in the 1950s. 

An air blast destroyed many windows and doors because it produced a concussion shock wave similar to a huge nuclear weapon.  If the 12,000 ton asteroid traveling at 42,000 mph  had entered at a steeper angle the damage would have been much more severe since its blast wave would have been directed towards the ground. 

In a recent month we detected 6 objects which passed closer than the Moon as they missed the Earth  We simply do not have a good idea of the number of small space rocks which enter the Earth's neighborhood. 

The  NASA Near Earth Object Program will have new equipment and telescopes coming on line in the near future. These facilities will enable us to have a far greater chance of providing an early warning should a small space rock be on a collision course with planet Earth. Injuries will then be kept to a minimum when people are warned to stay away from doors and windows. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


40-Itokawa A Strange Space Peanut

Published PRX May 1, 2014
Recorded April 27, 2014
remixed July 15, 2014 

The asteroid Itokawa [e toe kawa] is as odd as a barbell with a 29 lb weight on one end and and 18 lb weight on the other. It was discovered in 1998  as a moving point of light in the night sky by the LINEAR project in New Mexico.  It was  named for the Japanese  scientist whose rockets put his nations first satellite in orbit in 1970.

Itokawa orbits the Sun every 1.5 years on a path which crosses the Earth's orbit. It's size and close approaches to Earth make it a Potentially Hazardous Asteroid which deserves special attention.

In 2001 itokawa was imaged by the NASA Goldstone RADAR telescope and found to be an elongated object approximately 6 football fields long by 3 football fields wide.  In 2005 it was visited by the Hayabusa [Hi ya Boos ah] spacecraft which took images and returned samples to  Earth for analysis. 

Recently Dr. Steven Lowry of Kent University announced that his group has been monitoring the rate of spin of Itokawa for 12 years. Its spin rate is slowly increasing under the influence of sunlight.  These measurements along with a knowledge of the asteroid's shape from spacecraft data reveal that one half of the peanut shaped asteroid is nearly twice as dense the other half.    What looks like a simple bolder strewn exterior harbors a very complex internal structure.

It is important to understand this type of double trouble asteroid in case one of them is found to be a collision course with our Planet.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer



41-Navigating The Night Sky

Published PRX May 8, 2014
Recorded April 27, 2014
remixed July 15, 2014

To the human eye the night sky is a source of mystery and wonder. Our ancestors knew it well.  There is a connection to the cosmos that is hard to describe which you will achieve by knowing the names of some of the bright stars.  As the seasons progress, the feeling of greeting an old friend is generated, when one of the stars you know first appears in the evening sky. Scientifically we know that the Universe is evolving in many ways. Some of these changes  are apparent to the naked eye, however, over the course of the human life span there is constancy in the patterns we see in the night sky.  

Download the Kepler Star Wheels on the travelersinthenight.org website.  Use a large paper clip to hold the wheel in the holder after you have set it. Check on the current position of the bright planets since they are not on the star wheel. You will need is a flashlight with red filter material attached with a rubber band and also a compass.

Face North, hold the wheel so that the Northern Horizon is at the bottom, and find the North Star Polaris. There are 16 other naked eye stars with names listed on the star wheel. Face South and find one of them. Then face East and West and do the same.  Find a little pattern near each bright star to help jog your memory.  After several sessions you will be able to find bright stars without the wheel and you will have added to your knowledge in a fun way. 

Look at the area of the sky where the NASA Kepler Space Craft has found an Earth like planet which is at the right distance from its star to allow life as we know it to exist.  What do you think might live on that planet?

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

Go to travelersinthenight.org for star wheels and more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


42-Astronauts Reveal Sobering Data On Asteroid Impacts

Published PRX May 8, 2014
Recorded April 27, 2014
remixed July 15, 2014

On Earth Day  Astronauts Dr. Ed Lu, Tom Jones, and Bill Anders announced that between 2000 and 2013, the Nuclear Test Ban Treaty Organization Network detected 26 explosions on Earth ranging in energy from 1-600 kilotons of TNT. None of them were caused by nuclear explosions, but rather by asteroid impacts. Most of these asteroids exploded  high in the atmosphere and did no damage on the ground. These data provide a measure of the frequency at which large space rocks enter our atmosphere.

The Earth is continuously colliding with space rocks of various sizes. In 1908 one exploded at Tunguska, Siberia killing 80 million trees over an 800 square mile area. Asteroid impacts with an greater energy than the atomic bomb that destroyed Hiroshima in 1945 occurred in Indonesia in 2009, in the Southern Ocean in 2004, and in the Mediterranean Sea in 2002. In February of 2013 a small asteroid exploded over Russia injuring 1491 people.  The Astronauts make the point that none of these asteroids were detected or tracked in advance by any existing space-based or terrestrial observatory.  

The Astronauts are attempting to raise $450 million to cover the development and cost of the Sentinel Space Telescope. It goal is to find 90% of the asteroids which could leave a hurricane sized area of destruction should they impact the Earth.  You can make a donation on the B612 Foundation website.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


 

43-First Earth-Size Planet in 'Habitable Zone'

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Published PRX May 15, 2014
Recorded May 7, 2014
remixed July 15, 2014


The Kepler Space Craft has found tiny regular dips in light from a star which is about 500 light years away in the constellation of Cygnus. The dips in brightness come about when planets pass between their star and the Earth. This particular star has at least 5 planets. One of them is named Kepler-186f. It is similar to the Earth in size and is located at a distance from its star which may allow life as we know it to exist.
This newly discovered cousin to our Earth orbits a M dwarf star which is very much cooler than our Sun. Its year is only 130 days long.

Suppose that the temperature and atmospheric conditions on this newly discovered Earth like planet are conducive to the development of human like creatures. Can we imagine what they might look like?

A hint as to how difficult this might be comes from the fact that on Earth our eyes have a structure which is tuned to be most sensitive to the light emitted by our Sun. Beings which have developed on a planet orbiting an M dwarf star will have eyes of unfamiliar size and shape since their star puts out a pattern of radiation which is very different from our Sun.

Another variable is the mass and thus the force of gravity on a planet's surface. Beings on a planet with either more or less gravity than Earth would be likely to have sizes and shapes which are hard to imagine.

In the future NASA missions like the Transiting Exoplanet Survey Satellite and the James Webb Space Telescope will discover and measure properties of nearby Earth like planets. If any of them harbor life may be hard to determine.

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

Go to travelersinthenight.org for more information.
© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer




44-A Unique Metal World; Asteroid Psyche

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Published PRX May 15, 2014
Recorded May 07, 2014

The asteroid Psyche is named for a Greek mythological figure. It  was discovered in 1852 as a moving point of light in the night sky.  This small world is about 155 miles in diameter and orbits the Sun between Mars and Jupiter every 5 years. 

The mass of an asteroid can be determined in principle, by how its gravity effects other objects which it encounters.  An asteroid's size can be determined by how it dims a star as it passes between the star and us. The size and mass of Psyche suggest that it is dense enough to consist largely of iron. This hypothesis is supported by radar observations. These data suggest that the asteroid Psyche may be the core of what was once a rocky proto planet which lost its outer layers during catastrophic collisions in the early solar system. 

The iron world Psyche is unique among the many millions of asteroids in our Solar System which are composed of some combination rocks and ice.

Dr. Elkins-Tanton and her colleagues propose that NASA send a robotic space craft to orbit the asteroid Psyche for 6 months. During that time it would take images, measure magnetic fields, and make an accurate mass determination. 

The Earth's core and magnetic field effects our weather and climate. However, we can't travel to the center of the Earth.  Instead we must rely on earthquake waves to know anything about what is at our planet's core.  A visit to Psyche would allow us to directly study a naked planet's core and provide clues as to the nature of what is beneath our feet. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


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45-A World Full of Holes

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Published PRX May 27, 2014
Recorded May 08, 2014


 It may surprise you to know that there are more than 180 confirmed  impact craters on our planet.  It is likely that many more have been erased by the actions of wind and water.

The study of Earth's impact craters has much to tell us.  Asteroid impacts are widely viewed as a danger to life on our planet.  Can the reverse be true? Could an asteroid impact help life get started or preserve evidence of past life? 

Recently, Dr. Haley Sapers and her colleagues at the University of Western Ontario have discovered microscopic fossils in impact glass formed when an asteroid slammed into what is now Germany 15 million years ago. Other non-organic processes which occur on Earth cannot easily explain the distribution and shapes of the tubular features she found. It is likely these microscopic structures were formed by microbes etching their way through the meteor impact glass with organic acids which they excreted.

In another study, Dr. Pete Schultz and his research associates at Brown University have found fragments of leaves and organic compounds in meteor impact glass from Argentina. The plant material they found was preserved when it was quickly heated to more than 1500 C by the asteroid impact.  

An asteroid smashing  into a water rich world like  Earth or Mars can generate  reservoirs of hot water which may be a good place for early life to start.   It could also preserve ancient life forms in impact glass.  Perhaps impact craters  are the places to search for evidence that life has existed on Mars.

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

Go to travelersinthenight.org for more information.


© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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46-How Far Is Forever

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Published PRX May 27, 2014
Recorded May 08, 2014


When you look out in space you are also looking back in time.  Objects in space are older than they appear to us; the Moon more than a second  , Mars a  minute and a half,  and the Great Galaxy in Andromeda appears as it was 3 million years ago.  This situation is due to the fact that it takes time for light to travel the great distances in the Universe. 

You can experience this effect by observing a distant thunderstorm. On Earth light travels so fast that you see the lightning flash immediately after it happens.  On the other hand sound takes about 5 seconds to travel a mile. Therefore  if you see a lightning flash and hear the thunder10 seconds later, you are hearing sound from an event that happened 10 seconds in the past.

The NASA Hubble Space Telescope was pointed at a spot in the sky about 1/30 the width of your finger held at arms length. It was selected because it contains no objects which would block the view into deep space.  Hubble took more than 2,000 images of this dot in the sky over a 10 year period of time.  When they were combined electronically the resultant image contains 5,500 galaxies.  The most distant galaxies  appear as they were 13.2 billion years ago. Dr Garth Illingworth of the University of California at Santa Cruz, the principal investigator, points out that the Hubble Deep Field is the deepest image of the sky ever obtained.

In this one image you are able to travel in time down a corridor which leads from the time when galaxies like our Milky Way were  formed to about 450 million years after the Universe came into being with the big bang. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer





47-Earth Approaching Space Rocks Collected Over 6 Nights

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Published PRX May 29, 2014
Recorded May 27, 2014
remixed July 15, 2014


During a recent 6 night observing run with the NASA funded Catalina Sky Survey 60 inch telescope on Mt. Lemmon, I found 29 Earth Approaching Asteroid candidates which were posted on the Minor Planet Center website. Thirteen of these were designated as Near Earth Objects.  The largest of these is about 1/2 of a mile in diameter and the smallest about the size of a semi trailer truck.  These asteroids come from between 2.3 to 82 times the distance to our Moon from the Earth.  Five of them would produce major damage if they were to impact the Earth.  The other 8 are larger than the one which entered the Earth's atmosphere over Russia in February of 2013 injuring 1491 people.    Fortunately, none of the 13 will hit the Earth anytime soon.

A Potentially Hazardous Asteroid is one which is larger than about 1.5 football fields in diameter and gets closer to the Earth than about 5% of the distance to the Sun. One of these space rocks fits this definition. Two others narrowly miss being classified as potentially hazardous. 

The largest of this collection of space rocks is 2014 JO25. It orbits the Sun every 3 years and is about 1/2 mile in diameter.  Its closet approach to Earth is about 4.4 times the distance to our Moon at which time it is traveling in excess of 20 miles/second. We will continue to observe it, to make sure that it does not become an Earth impactor, as it passes near other objects in space.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


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48-Large Dangerous Asteroids Still Appear Suddenly Without Warning

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Published PRX May 29, 2014
Recorded May 27, 2014


At the beginning of a night of asteroid hunting with the NASA funded Catalina Sky Survey 60 inch telescope, my wife Annie called and wished that any asteroids, I find, would miss our planet. Within minutes of that call I was looking at images of the fastest brightest asteroid I had ever seen. Over the next 3 days and nights it was observed by telescopes all over the world. It is a previously unknown asteroid with a diameter of about half a mile. It literally came out of nowhere and brightened more than 250 times, in15 days, as it came from behind the Sun and headed back out into space.

Asteroid 2014 JO25 is truly an amazing object. It orbits the Sun, every 2.94 years, on a very elongated path that goes closer to the Sun than Mercury and then it travels out to well past Mars.  It must be made of hard rocky material since during its close approach to the Sun it was traveling at 84 miles/second. At that point, it was closer to the Sun than the planet Mercury and probably had a surface temperature greater than 800 F. Fortunately this asteroid never gets closer than about 4.4 lunar distances from Earth.

If an asteroid of this size were to impact the Earth it would cause devastation over thousands of square miles and make a crater perhaps 12 Miles in diameter. If it landed in the ocean it would create a mega tsunami. It is classified as a potentially hazardous asteroid so we will be observing it to make sure that its path is not changed into an impact trajectory with the Earth as it passes by other objects in space.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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49-Earth Approaching Wannabees


Published PRX June 05, 2014
Recorded  June 01, 2014

During a recent 6 night observing run with the NASA funded Catalina Sky Survey 60 inch telescope on Mt. Lemmon, I found 29 Earth Approaching Asteroid candidates.  With further observations, sixteen of these turned out to be real asteroids which in fact do not make close approaches to Earth. They range in size from about 5 football fields to nearly a mile in diameter.


One of the more interesting objects in this group of space rocks is 2014 JS2. It is classified as a main belt asteroid and orbits the Sun every 3.7 years. It is slightly less than a mile in diameter. Its orbit is inclined by about 40 degrees to the plane where most of the objects in the solar system travel as they orbit the Sun. This suggests that 2014 JS2 had a close approach or even a collision with another object to put it in its current path.

Another interesting object in this group is 2014 JA.  It is a Mars crossing asteroid which orbits the Sun every 2.36 years. Its orbit is inclined 24 degrees to the plane of the solar system.

The other 14 asteroids in this group all have orbital inclinations of 20 degrees or more from the plane of the solar system. This indicates that they were placed on their current paths by an interaction with some other object.  

Even though the solar system objects are generally separated by large distances, this group of Earth Approaching Asteroid Wannabees suggests that collisions between asteroids have occurred during the 4.6 billion year history of the solar system. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


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50-Asteroid 2014 JO25: What An Incredible Ride


Published PRX June 6, 2014
Recorded June 06, 2014

On September 26, 2012,  unbeknownst to the human race, a 1/2 mile diameter asteroid reached it farthest distance from the Sun.  It was 3/4 of the way from the Sun to the planet Jupiter. 

Throughout  2013 this asteroid accelerated under the relentless pull of the Sun's gravity.   It crossed the Earth's orbit on February 10, 2014  at which time it was traveling at 38 miles per second relative relative to our planet.  No one on Earth saw it streak by even though it was bright enough for us to detect.  

On March 21, 2014 this asteroid made it closest approach to the Sun and was traveling at 84 miles per second.  On this day it received 16 times the solar energy that falls on our planet and probably had a surface temperature greater than 800 F.

As it approached the Earth's orbit ,  this Potentially Hazardous Asteroid literally came out of nowhere as it brightened 250 times in 15 days.  On May 5, 2014,  the NASA funded Catalina Sky Survey 60 inch telescope on Mt. Lemmon, AZ detected it.  It was the fastest brightest asteroid I had ever seen.

After 3 days of intensive observing by telescopes all over the world it was given the name 2014 JO25. It will reappear in about 3 years as it orbits the Sun.  Fortunately, its orbit never brings it closer than about 4 times the distance to our Moon.  We will need to keep track of it since the situation may change as it encounters other objects in space.  

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


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51-Asteroid 2007 VK184 - Eliminated As An Impact Risk to Earth

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Published PRX June 12, 2014
Recorded June 06, 2014

On November 12, 2007, Alex Gibbs, using the NASA funded Catalina Sky Survey Schmidt telescope, discovered a bright fast moving asteroid.  It was then observed by telescopes in Italy, England, Arizona, California, and Australia and given the name 2007 VK184.

This asteroid created a considerable amount of interest since, until recently, it posed the most significant threat of Earth impact of any known object for the next 100 years.  It is about 1 and a half football fields in diameter.  

The observations of 2007 VK184 for the 52 days following its discovery indicated that there was a chance of 1 in 2700 that this asteroid would impact the Earth on June 3, 2048.  This is a serious warning since if it entered the Earth's atmosphere and struck sedimentary rock it would release the energy of a large hydrogen bomb and create a crater more than a mile in diameter.  Statistically an asteroid of this size is expect to strike the Earth about every 11,000 years.

In March of 2014 Dr. David Tholen used the Canada-France-Hawaii telescope at the Mauna Kea Observatory in Hawaii to detect and track 2007 VK184.  His observations, the first in more than 5 years, were used to calculate a new orbit.  Fortunately, the new path poses no treat to the Earth and indicates that this asteroid will never get closer to us than about 6 times the distance to our Moon.   

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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52- Another Large Bright Suddenly Appearing Asteroid


Published PRX June 12, 2014
Recorded June 06, 2014

An unknown, quarter of a mile diameter asteroid, reached its furthest distance from the Sun on June 17, 2012.  At this point it was 80% of the way from the Sun to Jupiter. The next day it began to accelerate under the relentless pull of the Sun's gravity.  On January 05, 2014 it crossed the orbit of Mars and was traveling at 28 mi/sec relative to the Sun.  

By the time it reached the Earth's orbit on February 12, 2014 it was traveling at a speed of 27 miles/sec relative to our planet.  Even though it was bright enough to be spotted, it evaded detection as it streaked by.  It reached its closest point to the Sun on March 27, 2014 at which time was slightly further away from the Sun than the planet Mercury.  

It brightened 10,000 times as it approached and crossed the Earth's orbit. Several days later, astronomers at the SONEAR Observatory, in Brazil discovered it as it continued to move away from the Sun.  It was then observed by telescopes in Australia, New Mexico, Japan, Ukraine,  and New Zealand and given the name 2014 KP4.  It orbits the Sun every 3 and 1/2 years . 

It is the second,  bright, fast moving Potentially Hazardous Asteroid found in less than a month.  Fortunately it never gets closer to the Earth than about 18 times the distance to our Moon.  We will continue to observe to make sure that it does not become on an impact trajectory with the Earth as it passes other objects in space.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


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53- Where Is Juno

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Published PRX June 19, 2014

Recorded June 10, 2014

The planet Jupiter is less important to us than the Earth, Sun, and Moon. However, it hold clues about the formation of our solar system and does send some comets towards us while causing others to miss our home planet. 

The NASA Juno spacecraft began its 5 year trip to Jupiter on August 5, 2011.  In order to conserve rocket fuel, it will travel more than 18 times the distance from the Earth to the Sun.  It received a gravitational boost from Earth in October of 2013 and is on a path to rendezvous with Jupiter.  In August of 2016, an on board rocket will be fired to slow the space craft to put it into an 11 day polar orbit around the gas giant.  After completing its mission of 33 orbits the rocket will be once again be fired causing the spacecraft to enter and burn up in Jupiter's upper atmosphere.  It will be destroyed to prevent it from colliding with any of Jupiter's moons.   

Once in orbit, the Juno Spacecraft will use infrared and microwave sensors to look deep into Jupiter's atmosphere.  Astronomers will thus measure the distribution of water and oxygen in the largest planet in our solar system.  They will also be able to test theories of how our solar system formed by mapping the distribution of matter in Jupiter's interior and providing a better estimate of its core mass. 

Jupiter has much to tell us about the history of our solar system. The Juno spacecraft will unlock some of its secrets.  You can follow this mission's progress on the NASA Juno website.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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54- Tour a Neighbor World


Published PRX June 19, 2014
Recorded June 10, 2014

Our Moon is the only other world whose surface can be easily viewed by humans.  The 59% of its surface visible from Earth is about 53 times the area of the state of California.  It has a fascinating landscape which continues to impress observers.

You can use a small telescope or binoculars to view lava flows, mountains, craters, walls, wrinkle ridges, rays, and rills on our Moon.  Some of the craters have mountain peaks at their center. There are even craters on craters. Many of these landforms were created by the impact of asteroids or comets. Others were formed by volcanic activity on the Moon.  The Earth itself probably had many such features which have been erased over the eons by the actions of wind, water, and ice.  They are still there on the Moon because it has no atmosphere.

When the Moon is full it is at its brightest. However, this is not the best time to see its surface details.

Your driveway's surface seems rougher when viewed with your headlights at night.  This happens when light strikes features from the side rather than straight down.  In the same way, the Moon's features can be best seen along the line of dark and shadow which is called the terminator.  Every night as the Moon changes phases this line will be in a different place.
Use it to make the various features on the Moon easy to see.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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55-RADAR Telescopes Pair Up to Image Near-Earth Asteroid


Published PRX June 26, 2014

Recorded June 24, 2014

Recently NASA's NEOWISE space telescope discovered an asteroid which subsequently passed about 3 times the Moon's distance from Earth. More than 100 followup observations were obtained by ground based telescopes all over the world and it was named 2014 HQ124.  These data prove that it will not be a threat to Earth till past the year 2200.  Using the NEOWISE infrared observations, NASA Astronomer, Dr. Amy Mainzer obtained a preliminary diameter of 1200 feet for this asteroid.

During 2014 HQ124's recent approach to Earth, NASA RADAR telescopes at Goldstone, California and the Arecibo Observatory in Puerto Rico were used to obtain images over about a 4 1/2 hour period of time. 

The spectacular RADAR images show surface details on this asteroid  down to about 12 feet in diameter.  It is peanut shaped and may actually be two asteroids in contact with each other. This object has many interesting features including a very steep sided hill which can be clearly seen in the RADAR images.

2014 HQ124 is a Potentially Hazardous Asteroid which orbits the Sun every 9 and 1/2 months on a path which takes it near both Venus and Earth.     

RADAR observations of asteroids and comets are an important way to measure an objects size, shape, and rate of spin.  The precise distance measurements they provide make it possible to predict an object's path far into the future and thus determine if it is a risk to planet Earth. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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56-A Whopper or A Comet


Published PRX June 26, 2014
Recorded June 24, 2014

Ray Sanders  was observing with the NASA funded Catalina Sky Survey telescope on Mt. Bigelow, Arizona when he discovered a curious moving point of light in the night sky.  Over the next 72 hours this object was observed by more than a dozen observatories all around the world and given the name 2014 LJ21.  These data were used to find its path as it orbits the Sun every 5 years from near Mercury to out past Mars.

If 2014 LJ21 is an asteroid, its brightness suggests that it is about 1 and a quarter miles in diameter.  This estimate is based on the assumption that it reflects about 15% of the Sun light which strikes it. The impact of an asteroid this size would likely cause global climate change. 

On the other hand if 2014 LJ21 is a comet, we still know its path accurately, but don't have a good way to estimate its size.

Either way, an impact with our home planet would not be a good thing. Fortunately, this object never comes closer than about 10 times the Earth-Moon distance from us.  We will need to keep track of it to make sure that it does not become on an impact trajectory with the Earth.

How can we tell the difference between an asteroid and a comet?  A large telescope could be used to divide the light up into its component colors to see which are present and which are missing.  These data would reveal its composition and identity.  Alternatively, a long exposure photograph might reveal some  "fuzz" around it and letting us know it is a comet.

In the meantime we will just have to wonder if it is a whopper or a comet.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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57-Hold A Traveler In The Night In Your Hand


Published PRX July 3, 2014)
Recorded June 24, 2014

Imagine holding a rock as old as our solar system that has traveled billions of miles through space to reach its present location.  It might even be worth real money. We are talking about a meteorite that you have just discovered.

How do you find one?

First you will need a place to look.  A place that is not littered with rocks is best. Obtain permission from a private land owner to look on their property. If you live near Federal BLM land you can collect up to 10 pounds per year without a permit. The great plains has few surface rocks and can be a great place to find meteorites. There are strewn fields from known celestial falls that you can check out. 
There is also a web site which lists recent meteor falls. Remember, please do not trespass on others land.

Detecting equipment includes your eye, a powerful magnet, and a metal detector. Train your eye using published photographs. 

When you find an interesting rock,  does it have a thin black rind like dark glassy fusion crust?   Is it Magnetic? Is it heavier than other similar sized rocks?  Does it have thumbprint like features? If the answers to these questions are yes, you may have found a meteorite.

Next do further research on your find.  Hopefully you have found a real meteorite. Where did it come from? Possibilities include the asteroid belt between Mars and Jupiter or maybe even the Moon, Mars, or a comet.

Happy hunting.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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58-NASA Hunts for A Special Asteroid


Published PRX July 3, 2014
Recorded June 24, 2014

Several years ago the NASA funded Lincoln Near Earth Asteroid Research Program discovered an SUV sized asteroid which comes closer to Earth than about 1/6 of the distance to the Moon. It was named 2011 MD.  It remained a minor curiosity until the Spitzer Space Telescope spotted it again.

Dr. Michael Mommert of Northern Arizona University and his colleagues recently published a paper describing  Spitzer' s infrared imaging of 2011 MD.  These data reveal that this asteroid is not very dense and may be a loose collection of boulders or a larger rock surrounded by dust. The leader of the Spitzer team, Dr. David Trilling, also of Northern Arizona University, commented "So far, we've looked at two asteroids and found both of them to be really weird -- not at all like the one solid rock that we expected. We're scratching our heads".

2011 MD's mass and size make it a good candidate for NASA's plans to use a robotic space craft to intercept and redirect a small asteroid into an orbit around our Moon. So far 8 other small asteroids have been found to be suitable for this purpose. Once in orbit the captured asteroid will be visited by the manned Orion Spacecraft. The samples that Astronauts obtain and return to Earth will help us to prepare for the discovery that an asteroid is on a collision course with planet Earth.  

The Orion vehicle and the new Space Launch System are essential to develop the capability for human beings to transition from low Earth orbit to the exploration of the Moon and Mars.

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

Go to travelersinthenight.org for more information.


© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer


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59-Spotting Travelers In The Night

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Published PRX July 10, 2014
Recorded June 27, 2014

Travelers In The Night from outer space are closer than you may imagine.  If you were to go straight up more than 4 miles you would need supplementary oxygen to stay conscious.  At 50 - 70 miles, the realm of meteors, humans require a full space suit to survive. 

Meteors, shooting stars, or falling stars are small asteroids called meteoroids. They are traveling at  between 7 and 44 miles per second when they enter the Earth's atmosphere. Most of them range in size from a grain of sand to a piece of driveway gravel.  Large ones can produce fireballs which are brighter than the planet Venus.  Most of them will burn up miles above you, however, a very few of them produce fragments which survive to arrive on the Earth's surface.  We call these objects meteorites.

During the year, there are a dozen major meteor showers. Check out the American Meteor Society website for a complete listing.   

The best time to view meteors is generally after midnight on a clear, moonless night. You will see many more in a rural area than under city lights.  On nights not during a meteor shower, you may expect to view sporadic  meteors at the rate of between 2-4 and 8-16 per hour.  Some meteor showers produce more than 100 events per hour.  Rarely you will have a chance to view a meteor storm which will give you the feeling that you are seeing the Earth move through space. In 1966 one of these storms produced a WOW inspiring 40 meteors per second.

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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60-A Close Visit With A Message

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Published PRX July 10, 2014
Recorded June 27, 2014

Eric Christensen was observing with the NASA funded Catalina Sky Survey Telescope on Mt. Lemmon, Arizona when he discovered a bright fast moving object in the night sky. During the next 25 hours it was observed by telescopes in Arizona and France and given the name 2014 MH6.  It orbits the Sun in a bit over 16 months on a path which goes from closer than Venus to out past Mars. 

Four days before its discovery 2014 MH6 was so faint that it was completely invisible to humans. Its undetectability  was caused both by its distance from us and the fact that its lighted side faced away from Earth.

Forty one and a half hours before humans spotted it, this asteroid was less than 2/3 of the distance to the Moon from us and was moving away from Earth at 10 miles per second. Shortly after this time it was as its brightest relative to our planet.

When discovered 2014 MH6 was almost 6 Lunar distances from our planet as it continued to head away from the both the Earth and the Sun.  Less than 10 days after discovery this asteroid was once again invisible to humans.  

2014 MH6 is slightly smaller than the asteroid whose airburst caused more than 1000 flying glass injuries in Russia in February of 2013.  

Six hours before it made its closest approach to Earth, 2014 MH6 was bright enough to be detected if we had the telescopes to cover the sky.   Providing a warning before an asteroid this size impacts the Earth is challenging but doable. 

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

Go to travelersinthenight.org for more information.

© 2014 A. D. Grauer and ℗ 2014 A. D. Grauer

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