Posted on by Nancy Atkinson

Take a Look: Huge Asteroid to Fly By Earth in November

This radar image of asteroid 2005 YU55 was generated from data taken in April of 2010 by the Arecibo Radar Telescope in Puerto Rico. Image credit: NASA/Cornell/Arecibo

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A large space rock will pass close to Earth on November 8, 2011 and astronomers are anticipating the chance to see asteroid 2005 YU55 close up. Just like meteorites offer a free “sample return” mission from space, this close flyby is akin to sending a spacecraft to fly by an asteroid – just like how the Rosetta mission recently flew by asteroid Lutetia – but this time, no rocket is required. Astronomers are making sure Spaceship Earth will have all available resources trained on 2005 YU55 as it makes its closest approach, and this might be a chance for you to see the asteroid for yourself, as well.

“While near-Earth objects of this size have flown within a lunar distance in the past, we did not have the foreknowledge and technology to take advantage of the opportunity,” said Barbara Wilson, a scientist at JPL. “When it flies past, it should be a great opportunity for science instruments on the ground to get a good look.”

2005 YU55 is about 400 meters [1,300 feet] wide, and closest approach will be about 325,000 kilometers (201,700 miles) from Earth.

“This is the largest space rock we have identified that will come this close until 2028,” said Don Yeomans, manager of NASA’s Near-Earth Object Program Office at JPL, and Yeomans assured that we are in no danger from this asteroid.

“YU55 poses no threat of an Earth collision over, at the very least, the next 100 years,” he said. “During its closest approach, its gravitational effect on the Earth will be so miniscule as to be immeasurable. It will not affect the tides or anything else.”

Astronomers estimate that asteroids the size of YU55 come this close to Earth about every 25 years. We just haven’t had this much advance warning – a testament to the work that Yeomans and his team does at the NEO Program in detecting asteroids and detecting them early.

So, here’s a chance for a close-up look. The 70-meter (230-foot) newly upgraded Goldstone antenna in California, part of NASA’s Deep Space Network, will be imaging the asteroid with radar.

“Using the Goldstone radar operating with the software and hardware upgrades, the resulting images of YU55 could come in with resolution as fine as 4 meters per pixel,” said Benner. “We’re talking about getting down to the kind of surface detail you dream of when you have a spacecraft fly by one of these targets.”

Combining the radar images with ground-based optical and near-infrared observations, astronomers should get a good overview of one of the larger near-Earth objects.

Look for more information in the near future about observing campaigns for amateur astronomers of this object. At first, 2005 YU55 will be too close to the sun and too faint for optical observers. But late in the day (Universal Time) on Nov. 8, and early on Nov. 9, the asteroid could reach about 11th magnitude for several hours before it fades as its distance rapidly increases.

This radar image of asteroid 2005 YU55 was generated from data taken in April of 2010 by the Arecibo Radar Telescope in Puerto Rico. Image credit: NASA/Cornell/Arecibo

2005 YU55 was discovered in December 2005 by Robert McMillan, head of the NASA-funded Spacewatch Program at the University of Arizona, Tucson. In April 2010, Mike Nolan and colleagues at the Arecibo Observatory in Puerto Rico generated some ghostly images of 2005 YU55 when the asteroid was about 2.3 million kilometers (1.5 million miles) from Earth.

“The best resolution of the radar images was 7.5 meters [25 feet] per pixel,” said JPL radar astronomer Lance Benner. “When 2005 YU55 returns this fall … the asteroid will be seven times closer. We’re expecting some very detailed radar images.”

Radar antennas beam directed microwave signals at their celestial targets — which can be as close as our moon and as far away as the moons of Saturn. These signals bounce off the target, and the resulting “echo” is collected and precisely collated to create radar images, which can be used to reconstruct detailed three-dimensional models of the object. This defines its rotation precisely and gives scientists a good idea of the object’s surface roughness. They can even make out surface features, and astronomers hope to see boulders and craters on the surfaces of 2005 YU55, as well as detailing the mineral composition of the asteroid.

“This is a C-type asteroid, and those are thought to be representative of the primordial materials from which our solar system was formed,” said Wilson. “This flyby will be an excellent opportunity to test how we study, document and quantify which asteroids would be most appropriate for a future human mission.”
Yeomans said this is a great opportunity for scientific discovery. “So stay tuned. This is going to be fun.”

Source: JPL

Posted on by Nancy Atkinson

Asteroid Observing Alert

2011 GP59 imaged remotely from the GRAS Observatory. Credit: Ernesto Guido & Giovanni Sostero

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A newly discovered asteroid could provide one of the best recent viewing opportunities for amateur astronomers, according to the British Astronomical Association. “This is the best NEO close approach these past few years and is bright enough to be observed visually in large (>20cm., or 8-inch) aperture telescopes when on the night of Thursday 14th it will appear as a faint slow-moving star,” writes Richard Miles, the director of the BAA’s Asteroids and Remote Planets Section.

UPDATE: See a new picture of asteroid 2011 GP59 from Ernesto Guido & Giovanni Sostero taken on April 14, 2011, below.


2011 GP59 imaged remotely from the GRAS Observatory. Credit: Ernesto Guido & Giovanni Sostero

Guido & Sostero sent us a note that they imaged 2011 GP59 early on April 14, remotely from the GRAS Observatory (near Mayhill, New Mexico USA) through a 0.51-m, f/6.9 reflector + CCD.

“It’s a single unfiltered exposure of 600 seconds, showing 2011 GP59 as trail with brightness fluctuations clearly evident,” they said.

(end of 4/14 update)

2011 GP59 was discovered just a few days ago and will make its closest approach to the Earth on April 15 at 19h UT at 1.39 lunar-distances. But it will be brightest at an average magnitude of 13.2 around 00h UT on the night of April 14/15 when Miles says it will be very favorably placed in the sky for observers worldwide.
The asteroid is approximately 60 meters in diameter and appears to be rotating very quickly, about once every 7.35 minutes. Its oblong in shape and rotation will vary the object’s brightness every 4 minutes or so.

Miles reported that David Briggs observing with the Hampshire Astronomy Group’s 0.4-m instrument on the evening of April 11 commented, “This is probably the fastest rotator I’ve seen so far in that it completely disappears from view every 3 to 4 images.”

This object was discovered on the night of April 8/9 by the Observatorio Astronomico de Mallorca (OAM) using a 0.45-m f/2.8 reflector at their La Sagra facilities (J75) in Andalusia, Spain (see http://www.minorplanets.org/OLS/ ). The observers involved were S. Sanchez, J. Nomen, R. Stoss, M. Hurtado, J. A. Jaume and W. K. Y. Yeung.

Brian Skiff of Lowell Observatory has completed a lightcurve analysis which can be found at this link, and positions can be found using the Minor Planet Center’s ephemeris service at this link. You can also find more information on this object from the website of the Remanzacco Observatory in Italy.

The British Astronomical Association is also seeking observations of the Moon on Friday, April 15, between 19:00 and 21:00 UT, when the Aristarchus and Herodotus area of the Moon will match the same illumination, to within +/- 0.5 degrees, as that observed during the famous Transient Lunar Phenomena (TLP) seen by Greenacre and Barr from Flagstaff observatory back on Oct. 30, 1963.

TLPs are very short changes in the brightness of patches on the face of the Moon, which can last anywhere from a few seconds to a few hours and can grow from less than a few to a hundred kilometers in size. This phenomenon has been observed by hundreds of amateur and professional astronomers, but how and why this occurs is not understood. Some astronomers believe that they are the outcome of lunar outgassing, where gas is being released from the surface of the Moon, but most commonly astronomers think it could be an effect from Earth’s own atmosphere.

If you want to help understand TLPs and perhaps observe an event like this for yourself, the BAA Lunar Section is looking for high resolution monochrome, or especially color, images of this area during this time period,, which favors observers in Europe.

But you can check this website from the University of Aberystwyth for many locations around the world of when would be a good time to observe a TLP.

See more information about how to observe a TLP and how to report your observations at the BAA website.

Sources: BAA, BAA (again) University of Aberystwyth

Posted on by Nancy Atkinson

Earth Has A Companion Asteroid With a Weird Orbit

Illustration of the Sun-Earth Lagrange Points. Credit: NASA

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There are plenty of near-Earth asteroids out there, but this latest one studied by two researchers at Armagh Observatory in Northern Ireland is extremely rare in that it has a weird, horseshoe-shaped orbit. Not that Asteroid 2010 SO16 does an about-face and turns around in mid-orbit — no, the asteroid always orbits the Sun in the same direction. But because of its unique orbital path and the gravitational effects from both the Earth and the Sun, it goes through a cycle of catching up with the Earth and falling behind, so that from our perspective here on Earth, its movement relative to both the Sun and the Earth traces a shape like the outline of a horseshoe: it appears to approach, then shift orbit, and go farther away without ever passing Earth.

This asteroid was discovered on September 17, 2010 by the WISE Earth-orbiting observatory.

There are only a handful of other asteroids known to have a horseshoe orbit. But astronomers Apostolos Christou and David Asher say 2010 SO16’s absolute magnitude (H=20.7) makes this the largest object of its type known to-date. It is just a few hundred meters across, so the other asteroids are extremely small, and none of the other horseshoe asteroids have orbits that are likely to survive for more than a few thousand years. But the researchers did computer simulations of SO16’s orbit, which showed it could stay in its orbit for at least 120,000 years, maybe more.

For an asteroid to have such an orbit means it is in almost the same solar orbit as Earth, and both take approximately one year to orbit the Sun.

The Technology Review Blog explained it this way:

“Two points are worth bearing in mind. First, objects further from the Sun than Earth, orbit more slowly. Second, objects that are closer to the Sun orbit more quickly than Earth.

So imagine an asteroid with an orbit around the Sun that is just a little bit smaller than Earth’s. Because it is orbiting more quickly, this asteroid will gradually catch up with Earth.

When it approaches Earth, the larger planet’s gravity will tend to pull the asteroid towards it and away from the Sun. This makes the asteroid orbit more slowly and if the asteroid ends up in a orbit that is slightly bigger than Earth’s, it will orbit the Sun more slowly than Earth and fall behind.

After that, the Earth will catch up with the slower asteroid in the bigger orbit, pulling it back into the small faster orbit and process begins again.

So from the point of view of the Earth, the asteroid has a horseshoe-shaped orbit, constantly moving towards and away from the Earth without ever passing it. (However, from the asteroid’s point of view, it orbits the Sun continuously in the same direction, sometimes more quickly in smaller orbits and sometimes more slowly in bigger orbits.)”

Right now, SO16 is near one of its closest points of approach, chasing the Earth on its inside orbit. It will be tagging along near Earth for the next few decades until it is pulled all the way over into the outside orbit and it slowly recedes from view.

The researchers say the existence of this long-lived horseshoe raises the twin questions of its origin and whether objects in similar orbits are yet to be found. Additionally, they suggest that SO16 may be a suitable test target for the direct detection of the Yarkovsky acceleration as it makes frequent close encounters with the Earth during the next decade.

Paper: “A long-lived horseshoe companion to the Earth”

Sources: Technology Review Blog, Wikipedia

Posted on by Nancy Atkinson

Astronomers Continue to Monitor Asteroid Apophis

Apophis (circled) in a composite of five exposures taken on January 31 with the University of Hawaii 2.2-meter telescope on Mauna Kea. Image by D. Tholen, M. Micheli, G. Elliott, UH Institute for Astronomy.

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Asteroid Apophis continues to be an object of interest for astronomers. Even though the possibility of an Earth impact by the now-famous asteroid has been ruled out during its upcoming close encounter on April 13, 2029, this close flyby will significantly change Apophis’s orbit, and astronomers are uncertain how that could affect future encounters with our planet. For that reason, astronomers have been eager to obtain new data to further refine the details of the 2029 encounter. However, for three years, the asteroid’s orbit had it “hiding” behind the Sun, but it has now emerged. This newest image of Apophis was taken on January 31, 2011, using the University of Hawaii’s 2.2-meter telescope on Mauna Kea, and astronomers from UH at Manoa say they will make repeated observations of this potentially dangerous near-Earth asteroid.

Astronomers measure the position of an asteroid by comparing with the known positions of stars that appear in the same image as the asteroid. As a result, any tiny error in the catalog of star positions, due for example to the very slow motions of the stars around the center of our Milky Way galaxy, can affect the measurement of the position of the asteroid.

“We will need to repeat the observation on several different nights using different stars to average out this source of imprecision before we will be able to significantly improve the orbit of Apophis and therefore the details of the 2029 close approach and future impact possibilities,” said astronomer David Tholen, one of the co-discoverers of Apophis, who made the latest observations along with graduate students Marco Micheli and Garrett Elliott.

They obtained the new images when the 270-meter (900-foot) diameter asteroid was less than 44 degrees from the sun and about a million times fainter than the faintest star that the average human eye can see without optical aid.

The astronomers will be taking advantage of Apophis’s position for the next few months, as its elliptical orbit around the Sun will take it back into the sun’s glare this summer, making observations – and measurements of its position – impossible. However, in 2012, Apophis will again become observable for approximately nine months. In 2013, the asteroid will pass close enough to Earth for ultraprecise radar signals to be bounced off its surface.

“Radar observations are important because we can estimate orbital parameters and provides us lots of information about an asteroid’s surface features and internal structure, and how they may have formed,” said Lance Benner, an astronomer at JPL, who specializes in radar imaging of near-Earth asteroids. “We need to know these things if we are going to deflect one of these.” Speaking at the American Geophysical Union conference in 2009, Benner said radar is the most powerful astronomical technique for both finding new asteroids and measuring their orbits.

“We can measure their velocity to less than 1mm per second, and do this up to 20 million kilometers from earth. Radar helps us compute the trajectory much farther into the future – even up to 300 years, giving us much more advance notice.” Benner said they can routinely image asteroids at 7.5 meters per pixel, and a new system at the Goldstone radar facility will be able to get the resolution down to 1 meter per pixel.

On April 13, 2029, Apophis will come closer to Earth than the geosynchronous communications satellites that orbit Earth at an altitude of about 36,000 km (22,000 miles). Astronomers say Apophis will then be briefly visible to the naked eye as a fast-moving starlike object.

Source: University of Hawaii Institute for Astronomy

Posted on by Nancy Atkinson

New Record: Telescope Finds 19 Near-Earth Asteroids in One Night

Richard Wainscoat (left) and Marco Micheli study one of the near-Earth asteroids found on January 29. The asteroid is the roundish dot near Wainscoat’s finger. Photo by Karen Teramura

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From a University of Hawaii Institute for Astronomy press release:

The Pan-STARRS PS1 telescope on Haleakala, Maui, discovered 19 near-Earth asteroids on the night of January 29, the most asteroids discovered by one telescope on a single night.

“This record number of discoveries shows that PS1 is the world’s most powerful telescope for this kind of study,” said Nick Kaiser, head of the Pan-STARRS project. “NASA and the U.S. Air Force Research Laboratory’s support of this project illustrates how seriously they are taking the threat from near-Earth asteroids.”

Pan-STARRS software engineer Larry Denneau spent that Saturday night in his University of Hawaii at Manoa office in Honolulu processing the PS1 data as it was transmitted from the telescope over the Internet. During the night and into the next afternoon, he and others came up with 30 possible new near-Earth asteroids.
Asteroids are discovered because they appear to move against the background of stars. To confirm asteroid discoveries, scientists must carefully re-observe them several times within 12-72 hours to define their orbits, otherwise they are likely to be “lost.”

Denneau and colleagues quickly sent their discoveries to the Minor Planet Center in Cambridge, Mass., which collects and disseminates data about asteroids and comets, so that other astronomers can re-observe the objects.

“Usually there are several mainland observatories that would help us confirm our discoveries, but widespread snowstorms there closed down many of them, so we had to scramble to confirm many of the discoveries ourselves,” noted Institute for Astronomy astronomer Richard Wainscoat.

Wainscoat, astronomer David Tholen, and graduate student Marco Micheli spent the next three nights searching for the asteroids using telescopes at Mauna Kea Observatories, Hawaii.

On Sunday night, they confirmed that two of the asteroids were near-Earth asteroids before snow on Mauna Kea forced the telescopes to close. On Monday night, they confirmed nine more before fog set in.
On Tuesday night, they searched for four, but found only one. After Tuesday, the remaining unconfirmed near-Earth asteroids had moved too far to be found again.

Telescopes in Arizona, Illinois, Italy, Japan, Kansas, New Mexico, and the United Kingdom, and the Faulkes Telescope on Haleakala also helped to confirm seven of the discoveries.

Two of the asteroids, it turns out, have orbits that come extremely close to Earth’s. There is no immediate danger, but a collision in the next century or so, while unlikely, cannot yet be ruled out. Astronomers will be paying close attention to these objects.

Posted on by Nancy Atkinson

Small Asteroid Just Buzzed Earth

If you felt a sudden breeze at about 19:40 GMT (2:40 pm EST), it was probably from a small asteroid that came extremely close to the Earth today (Feb. 4, 2011). The object, officially designated 2011 CQ1, is fairly small — about 2-3 meters (6.5 -10 ft) wide — and at closest approach it came within 11,855 km (7,366 miles) or about 0.03 lunar distances (LD), or 0.00008 astronomical units (AU). Yep, that’s pretty close.

Richard Kowalski with the Catalina Sky Survey discovered this object early today. The image above is from Giovanni Sostero & Ernesto Guido who made remote follow-up observations to confirm with the Tzec Maun Observatory in New Mexico.

There was no chance this object was going to hit Earth, but it did come well within what is known as the Clarke Belt among geosynchronous satellites.

Find out more about the path this object is taking at Remanzacco Observatory in Italy.

Info on the Minor Planet Center website about 2011 CQ1.

Astronomer Bill Gray calculated a transit line plot showing the path over South America. You can see the charts here:

http://www.projectpluto.com/cq1.png

http://www.projectpluto.com/cq1a.png

And if you are an astrophotographer, let us know if you capture any images of 2011 CQ1.

Posted on by Nancy Atkinson

Mission Complete: NEOWISE Concludes Hunt for Near-Earth Objects

During its one-year mission, NASA's Wide-field Infrared Survey Explorer, or WISE, mapped the entire sky in infrared light. Among the multitudes of astronomical bodies that have been discovered by the NEOWISE portion of the WISE mission are 20 comets. Image credit: NASA/JPL-Caltech/UCLA

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The WISE spacecraft has completed a special mission called NEOWISE, looking for small bodies in the solar system, and has discovered a plethora of previously unknown objects. The NEOWISE mission found 20 comets, more than 33,000 asteroids in the main belt between Mars and Jupiter, and 134 near-Earth objects (NEOs). More data from NEOWISE also have the potential to reveal a brown dwarf even closer to us than our closest known star, Proxima Centauri, if such an object does exist. Likewise, if there is a hidden gas-giant planet in the outer reaches of our solar system, data from WISE and NEOWISE could detect it.

“WISE has unearthed a mother lode of amazing sources, and we’re having a great time figuring out their nature,” said Edward (Ned) Wright, the principal investigator of WISE at UCLA.

“Even just one year of observations from the NEOWISE project has significantly increased our catalog of data on NEOs and the other small bodies of the solar systems,” said Lindley Johnson, NASA’s program executive for the NEO Observation Program.

The NEOs are asteroids and comets with orbits that come within 45 million kilometers (28 million miles) of Earth’s path around the sun.

The NEOWISE mission made use of the the WISE spacecraft, the Wide-field Infrared Survey Explorer that launched in December 2009. WISE scanned the entire celestial sky in infrared light about 1.5 times. It captured more than 2.7 million images of objects in space, ranging from faraway galaxies to asteroids and comets close to Earth.

However, in early October 2010, after completing its prime science mission, the spacecraft ran out of the frozen coolant that keeps its instrumentation cold. But two of its four infrared cameras remained operational, which were still optimal for asteroid hunting, so NASA extended the NEOWISE portion of the WISE mission by four months, with the primary purpose of hunting for more asteroids and comets, and to finish one complete scan of the main asteroid belt.

Now that NEOWISE has successfully completed a full sweep of the main asteroid belt, the WISE spacecraft will go into hibernation mode and remain in polar orbit around Earth, where it could be called back into service in the future.

In addition to discovering new asteroids and comets, NEOWISE also confirmed the presence of objects in the main belt that had already been detected. In just one year, it observed about 153,000 rocky bodies out of approximately 500,000 known objects. Those include the 33,000 that NEOWISE discovered.

NEOWISE also observed known objects closer and farther to us than the main belt, including roughly 2,000 asteroids that orbit along with Jupiter, hundreds of NEOs and more than 100 comets.

These observations will be key to determining the objects’ sizes and compositions. Visible-light data alone reveal how much sunlight reflects off an asteroid, whereas infrared data is much more directly related to the object’s size. By combining visible and infrared measurements, astronomers also can learn about the compositions of the rocky bodies — for example, whether they are solid or crumbly. The findings will lead to a much-improved picture of the various asteroid populations.

NEOWISE took longer to survey the whole asteroid belt than WISE took to scan the entire sky because most of the asteroids are moving in the same direction around the sun as the spacecraft moves while it orbits Earth. The spacecraft field of view had to catch up to, and lap, the movement of the asteroids in order to see them all.

“You can think of Earth and the asteroids as racehorses moving along in a track,” said Amy Mainzer, the principal investigator of NEOWISE at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We’re moving along together around the sun, but the main belt asteroids are like horses on the outer part of the track. They take longer to orbit than us, so we eventually lap them.”

NEOWISE data on the asteroid and comet orbits are catalogued at the NASA-funded International Astronomical Union’s Minor Planet Center, a clearinghouse for information about all solar system bodies at the Smithsonian Astrophysical Observatory in Cambridge, Mass. The science team is analyzing the infrared observations now and will publish new findings in the coming months.

The first batch of observations from the WISE mission will be available to the public and astronomical community in April.

Source: NASA

Posted on by Nancy Atkinson

Asteroid Apophis in the News Again

Annimation of Apophis. Image Credit: Osservatorio Astronomico Sormano

It must have been a slow news day in Russia yesterday (actually – and unfortunately — it wasn’t)… as headlines from one of Russia’s leading news agencies, Ria Novosti, proclaimed, “Russian Astronomers Predict Apophis-Earth Collision in 2036.” But reading the article a little further, the astronomer, Leonid Sokolov of St. Petersburg State University says the chance of a collision in 2036 is extremely slim, which is exactly what NASA’s Near-Earth Object Program has been saying for several years. So, just to be clear, there is no new information or changes in understanding Apophis’ orbit. Here are the facts:

Continue reading “Asteroid Apophis in the News Again”

Posted on by Nancy Atkinson

More Asteroids Could Have Made Life’s Ingredients

This artist's concept uses hands to illustrate the left and right-handed versions of the amino acid isovaline. Credit: NASA/Mary Pat Hrybyk-Keith

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From a NASA press release:

A wider range of asteroids were capable of creating the kind of amino acids used by life on Earth, according to new NASA research. Amino acids are used to build proteins, which are used by life to make structures like hair and nails, and to speed up or regulate chemical reactions. Amino acids come in two varieties that are mirror images of each other, like your hands. Life on Earth uses the left-handed kind exclusively. Since life based on right-handed amino acids would presumably work fine, scientists are trying to find out why Earth-based life favored left-handed amino acids.

In March, 2009, researchers at NASA’s Goddard Space Flight Center in Greenbelt, Md., reported the discovery of an excess of the left-handed form of the amino acid isovaline in samples of meteorites that came from carbon-rich asteroids. This suggests that perhaps left-handed life got its start in space, where conditions in asteroids favored the creation of left-handed amino acids. Meteorite impacts could have supplied this material, enriched in left-handed molecules, to Earth. The bias toward left-handedness would have been perpetuated as this material was incorporated into emerging life.

In the new research, the team reports finding excess left-handed isovaline (L-isovaline) in a much wider variety of carbon-rich meteorites. “This tells us our initial discovery wasn’t a fluke; that there really was something going on in the asteroids where these meteorites came from that favors the creation of left-handed amino acids,” says Dr. Daniel Glavin of NASA Goddard. Glavin is lead author of a paper about this research published online in Meteoritics and Planetary Science January 17.

This is a photo of a carbon-rich meteorite analyzed in the study. Credit: Antarctic Meteorite Laboratory/NASA Johnson Space Center

“This research builds on over a decade of work on excesses of left-handed isovaline in carbon-rich meteorites,” said Dr. Jason Dworkin of NASA Goddard, a co-author on the paper.

“Initially, John Cronin and Sandra Pizzarello of Arizona State University showed a small but significant excess of L-isovaline in two CM2 meteorites. Last year we showed that L-isovaline excesses appear to track with the history of hot water on the asteroid from which the meteorites came. In this work we have studied some exceptionally rare meteorites which witnessed large amounts of water on the asteroid. We were gratified that the meteorites in this study corroborate our hypothesis,” explained Dworkin.

L-isovaline excesses in these additional water-altered type 1 meteorites (i.e. CM1 and CR1) suggest that extra left-handed amino acids in water-altered meteorites are much more common than previously thought, according to Glavin. Now the question is what process creates extra left-handed amino acids. There are several options, and it will take more research to identify the specific reaction, according to the team.

However, “liquid water seems to be the key,” notes Glavin. “We can tell how much these asteroids were altered by liquid water by analyzing the minerals their meteorites contain. The more these asteroids were altered, the greater the excess L-isovaline we found. This indicates some process involving liquid water favors the creation of left-handed amino acids.”

Another clue comes from the total amount of isovaline found in each meteorite. “In the meteorites with the largest left-handed excess, we find about 1,000 times less isovaline than in meteorites with a small or non-detectable left-handed excess. This tells us that to get the excess, you need to use up or destroy the amino acid, so the process is a double-edged sword,” says Glavin.

Whatever it may be, the water-alteration process only amplifies a small existing left-handed excess, it does not create the bias, according to Glavin. Something in the pre-solar nebula (a vast cloud of gas and dust from which our solar system, and probably many others, were born) created a small initial bias toward L-isovaline and presumably many other left-handed amino acids as well.

One possibility is radiation. Space is filled with objects like massive stars, neutron stars, and black holes, just to name a few, that produce many kinds of radiation. It’s possible that the radiation encountered by our solar system in its youth made left-handed amino acids slightly more likely to be created, or right-handed amino acids a bit more likely to be destroyed, according to Glavin.

It’s also possible that other young solar systems encountered different radiation that favored right-handed amino acids. If life emerged in one of these solar systems, perhaps the bias toward right-handed amino acids would be built in just as it may have been for left-handed amino acids here, according to Glavin.

The research was funded by the NASA Astrobiology Institute (NAI), which is administered by NASA’s Ames Research Center in Moffett Field, Calif.; the NASA Cosmochemistry program, the Goddard Center for Astrobiology, and the NASA Post Doctoral Fellowship program. The team includes Glavin, Dworkin, Dr. Michael Callahan, and Dr. Jamie Elsila of NASA Goddard.

Posted on by Ken Kremer

Deep Space Radar Unveils Rotating Asteroid 2010 JL33

A radar image of asteroid 2010 JL33, generated from data taken by NASA's Goldstone Solar System Radar on Dec. 11 and 12, 2010. Image credit: NASA/JPL-Caltech

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Intriguing details about the physical properties and characteristics of a recently discovered asteroid have just been unveiled in amazing images obtained using a large radar dish in California. The radar dish serves as a key component of NASA’s Deep Space Network (DSN). The Near Earth asteroid, dubbed 2010 JL33, was imaged by radar on Dec. 11 and 12, 2010 at NASA’s Goldstone Solar System Radar in California’s Mojave Desert when a close approach to Earth offered an outstanding opportunity for high quality science.

Asteroids studies have taken on significantly increased importance at NASA ever since President Obama decided to cancel the Constellation ‘Return to the Moon’ program and redirect NASA’s next human spaceflight goal to journeying to an Asteroid by around 2025.

Update: Orbital diagram added below
A sequence of 36 amazingly detailed images has been assembled into a short movie (see below) by the science team at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif. The movie shows about 90 percent of one rotation.

The data gathered by radar revealed that the asteroid measures roughly 1.8 kilometers (1.1 miles) in diameter and rotates once every nine hours.

Orbital diagram of Asteroid 2010 JL33 shows location as of Jan 14, 2011. Credit: NASA
click to enlage all images

“Asteroid 2010 JL33 approached within 17 Earth-Moon distances [some 7 million km] in December 2010 and offered an outstanding opportunity to study it with radar,” said Lance Benner, a scientist at JPL who studies asteroids.

“To get detailed radar images, an asteroid must be close to Earth,” Benner told me, for Universe Today.

The object was only discovered on May 6 by the Mount Lemmon Survey in Arizona. The radar observations were led by a team headed by JPL scientist Marina Brozovic.

Video Caption: While safely passing Earth, NASA’s Goldstone Solar System Radar captured the rotation of asteroid 2010 JL33 — an irregular, elongated object roughly 1.8 kilometers (1.1) miles wide. The video consists of 36 frames.

“The radar images we got enabled us to estimate the asteroid’s size, rotation period, and to see features on its surface, most notably, the large concavity that appears as a dark region in the collage,” Benner elaborated.

“It was discovered so recently that little else is known about it.”

The object was revealed to be elongated and irregularly shaped.

70-meter diameter NASA Deep Space Network (DSN) antenna at Goldstone, California.

The 70-meter (230-foot) diameter antenna is the largest, and therefore most sensitive, DSN antenna, and is capable of tracking a spacecraft travelling more than 16 billion kilometers (10 billion miles) from Earth.
The surface of the 70-meter reflector must remain accurate within a fraction of the signal wavelength, meaning that the precision across the 3,850-square-meter (41,400 sq. ft.) surface is maintained within one centimeter (0.4 in.). Credit: NASA


The large concavity is clearly visible in the images and may be an impact crater. It took about 56 seconds for the radio signals from the 70-meter (230-foot) diameter Goldstone radar dish to make the roundtrip from Earth to the asteroid and back to Earth again.

“When we get deeper into our analysis of the data, we will use the images to estimate the three-dimensional shape of the asteroid as well,” Benner added.

Benner belongs to a team that is part of a long-term NASA program to study asteroid physical properties and to improve asteroid orbits using radar telescopes at Goldstone and also at the Arecibo Observatory in Puerto Rico. The 1,000-foot-diameter (305 meters) Arecibo radar dish antenna is operated by the National Science Foundation.

“Each close approach by an asteroid provides an important opportunity to study it, so we try to exploit as many such opportunities as possible to investigate the physical properties of many asteroids. In the bigger picture, this helps us understand how the asteroids formed,” Benner told me.

“Asteroid 2010 JL33 is in an elongated orbit about the Sun. On average, it’s about 2.7 times farther from the Sun than the Earth is, but its distance from the Sun varies from 0.7 to 4.6 times that of the Earth.” That takes the asteroid nearly out to Jupiter at Aphelion. It takes about 4.3 years to complete one orbit around the sun.

But, there’s no need to fret about disaster scenarios. “The probability of impact with Earth is effectively zero for the foreseeable future,” Benner explained.

“On rare occasions it approaches closely to Vesta,” he said. Vesta is the second most massive asteroid and will be visited for the first time by NASA’s Dawn spacecraft later this year.

In addition to the ground based radar imaging, the tiny space rock was investigated by an Earth orbiting telescope.

“This asteroid was also studied by NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft,” according to Benner. “Our observations will help WISE scientists calibrate their results because we provided an independent means to estimate the size of this object.”

More at this JPL press release. The NASA-JPL Near-Earth Object Program website has an interactive map that allows you to see the asteroid’s position at any time you desire. Go to here

To see the trajectory of any other near-Earth asteroid, go to here

For more information about asteroid radar research, go to here

Information about the Deep Space Network is here