Posted on by Nancy Atkinson

Hit and Run Asteroid Caused Scheila’s Comet-like Behavior

Faint dust plumes bookend asteroid (596) Scheila, which is overexposed in this composite. Visible and ultraviolet images from Swift's UVOT (circled) are merged with a Digital Sky Survey image of the same region. The UVOT images were acquired on Dec. 15, 2010, when the asteroid was about 232 million miles from Earth. Credit: NASA/Swift/DSS/D. Bodewits (UMD)

Asteroid or comet? That was the question astronomers were asking after an asteroid named Scheila had unexpectedly brightened, and seemingly sprouted a tail and coma. But follow-up observations by the Swift satellite and the Hubble Space Telescope show that these changes likely occurred after Scheila was struck by a much smaller asteroid.

“Collisions between asteroids create rock fragments, from fine dust to huge boulders, that impact planets and their moons,” said Dennis Bodewits, an astronomer at the University of Maryland in College Park and lead author of the Swift study. “Yet this is the first time we’ve been able to catch one just weeks after the smash-up, long before the evidence fades away.”

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On Dec. 11, 2010, images from the University of Arizona’s Catalina Sky Survey, a project of NASA’s Near Earth Object Observations Program, revealed the Scheila to be twice as bright as expected and immersed in a faint comet-like glow. Looking through the survey’s archived images, astronomers inferred the outburst began between Nov. 11 and Dec. 3.

Three days after the outburst was announced, Swift’s Ultraviolet/Optical Telescope (UVOT) captured multiple images and a spectrum of the asteroid. Ultraviolet sunlight breaks up the gas molecules surrounding comets; water, for example, is transformed into hydroxyl (OH) and hydrogen (H). But none of the emissions most commonly identified in comets — such as hydroxyl or cyanogen (CN) — showed up in the UVOT spectrum. The absence of gas around Scheila led the Swift team to reject the idea that Scheila was actually a comet and that exposed ice accounted for the brightening.

Hubble observed the asteroid’s fading dust cloud on Dec. 27, 2010, and Jan. 4, 2011. Images show the asteroid was flanked in the north by a bright dust plume and in the south by a fainter one. The dual plumes formed as small dust particles excavated by the impact were pushed away from the asteroid by sunlight.

The science teams from the two space observatories found the observations were best explained by a collision with a small asteroid impacting Scheila’s surface at an angle of less than 30 degrees, leaving a crater 1,000 feet across. Laboratory experiments show a more direct strike probably wouldn’t have produced two distinct dust plumes. The researchers estimated the crash ejected more than 660,000 tons of dust–equivalent to nearly twice the mass of the Empire State Building.

The Hubble Space Telescope imaged (596) Scheila on Dec. 27, 2010, when the asteroid was about 218 million miles away. Scheila is overexposed in this image to reveal the faint dust features. The asteroid is surrounded by a C-shaped cloud of particles and displays a linear dust tail in this visible-light picture acquired by Hubble's Wide Field Camera 3. Because Hubble tracked the asteroid during the exposure, the star images are trailed. Credit: NASA/ESA/D. Jewitt (UCLA)

“The Hubble data are most simply explained by the impact, at 11,000 mph, of a previously unknown asteroid about 100 feet in diameter,” said Hubble team leader David Jewitt at the University of California in Los Angeles. Hubble did not see any discrete collision fragments, unlike its 2009 observations of P/2010 A2, the first identified asteroid collision.

Scheila is approximately 113 km (70 miles) across and orbits the sun every five years.

“The dust cloud around Scheila could be 10,000 times as massive as the one ejected from comet 9P/Tempel 1 during NASA’s UMD-led Deep Impact mission,” said co-author Michael Kelley, also at the University of Maryland. “Collisions allow us to peek inside comets and asteroids. Ejecta kicked up by Deep Impact contained lots of ice, and the absence of ice in Scheila’s interior shows that it’s entirely unlike comets.”

The studies will appear in the May 20 edition of The Astrophysical Journal Letters.

Source: NASA Goddard

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 Tammy Plotner

Is Winking Near-Earth Asteroid GP59 Really the Missing Apollo 13 Panel?

Static Photo of GP59 Taken by Joe Brimacombe

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Is the recently discovered “winking” asteroid – GP59 – really the missing panel from the ill-fated Apollo 13 mission? According to the latest internet buzz, it could be as possible as Mars being as large as the full Moon…

With the recent anniversary of the Apollo 13 disaster conveniently coinciding with the discovery of “winking” near-Earth asteroid GP59, anxious theorists are ready to believe they are one and the same. Thanks to the asteroid’s rapid tumble and quick magnitude changes, it’s no small wonder that it would appear on the surface to be so. Just take a look at this GP59 Video done by Joe Brimacombe and you’ll see why.

With discoveries of artifacts continually found on Earth, such as missing pieces of the Titanic, it wouldn’t take a great leap of faith to believe we might have recovered one in space as well – even the panel that blew away from Apollo 13. However, we need to take a look at that equation times four – the 4 panels that protected the LM during launch – the Spacecraft Lunar Module Adapter (SLA) panels. Says Marshall Eubanks, ” In the Saturn V launches, the SLA panels were ejected, with separation velocity of about 2 meters / second. They were 6.4 meters tall, about 3 meters wide at the apex, made of a 0.043 meters thick aluminum honeycomb, plus about 1 mm of cork and paint, and so have a very low mass-area ratio. If 2011 GP59 is an SLA panel, then it should have 3 clones with very similar orbits.”

With today’s huge advances in amateur telescopes, there remains a possiblity – however small – that we may someday recover objects like these. “I could see a situation in which a panel was spinning around its short axis, with that axis tilted a bit toward the Sun, so that there would be a systematic pressure accelerating or decelerating it. (Sort of like what the fans of spin-stabilized solar sails hope to do.) The problem would be that over a full orbit around the Sun, the net acceleration would cancel out.” says Bill Gray. “The bottom line remains: there is no particularly good reason to think there’s a connection between these panels and 2011 GP59. (Even if the panels were big enough to match the observed brightness of 2011 GP59, which they aren’t.) If the panels are ever recovered, they’re apt to be in much more Earth-like orbits. With 36 of them out there, the odds seem decent that we’ll see one of them someday.”

But don’t hold your breath when it comes to GP59… it is what it is… a tumbling, oblong asteroid roughly 47 meters in diameter. “Usually, when we see an asteroid strobe on and off like that, it means that the body is elongated and we are viewing it broadside along its long axis first, and then on its narrow end as it rotates ,” said Don Yeomans, manager of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif. “GP59 is approximately 50 meters [240 feet] long, and we think its period of rotation is about seven-and-a-half minutes. This makes the object’s brightness change every four minutes or so.”

And our hearts skip a beat just thinking of the possiblities…

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

Two Asteroids Passed Close to Earth Wednesday

These are not the two asteroids that passed by Earth on Wednesday -- but is an illustration of a binary asteroid. (Credit: ESO/L. Calcada)

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Earth got a double dose of close asteroid flybys on Wednesday, April 6, 2011. Two newly discovered small asteroids both passed within the distance of the Moon. 2011 GW9 (10 meters wide) came within half the distance to the Moon, about 192,000 km 12:53 a.m. EDT and 2011 GP28 (6 meters wide) came within 77,000 km (.2 LD) at 3:36 p.m. EDT. Spaceweather.com said the size of these asteroids are two to three times smaller than the Tunguska impactor of 1908, and assured there was no danger of a collision with Earth.

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 Ken Kremer

Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

Virtual Vesta. Taking their best guess, the science team on NASA’s Dawn Asteroid Orbiter have created a series of still images and videos (see below) to simulate what the protoplanet Vesta might look like. The exercise was carried out by mission planners at NASA's Jet Propulsion Laboratory and science team members at the German Aerospace Center and the Planetary Science Institute. Image credit: NASA/JPL-Caltech/ESA/UCLA/DLR/PSI/STScI/UMd

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The excitement is building as NASA’s innovative Dawn spacecraft closes in on its first protoplanetary target, the giant asteroid Vesta, with its camera eyes now wide open. The probe is on target to become the first spacecraft from Earth to orbit a body in the main asteroid belt and is set to arrive about four months from now in late July 2011.

Vesta is the second most massive object in the Asteroid Belt between Mars and Jupiter (map below). Since it is also one of the oldest bodies in our Solar System, scientists are eager to study it and search for clues about the formation and early history of the solar system. Dawn will spend about a year orbiting Vesta. Then it will fire its revolutionay ion thrusters and depart for Ceres, the largest asteroid in our solar system.

Dawn is equipped with three science instruments to photograph and investigate the surface mineralogy and elemental composition of the asteroid. The instruments were provided by the US, Germany and Italy. The spacecraft has just awoken from a six month hibernation phase. All three science instruments have been powered up and reactivated.

Dawn will image about 80 percent of Vesta’s surface at muliple angles with the onboard framing cameras to generate topographical maps. During the year in orbit, the probe will adjust its orbit and map the protoplanet at three different and decreasing altitudes between 650 and 200 kilometers, and thus increasing resolution. The cameras were provided and funded by Germany.

To prepare for the imaging campaign, mission planners from the US and Germany conducted a practice exercise to simulate the mission as though they were mapping Vesta. The effort was coordinated among the science and engineering teams at NASA’s Jet Propulsion Laboratory, the Institute of Planetary Research of the German Aerospace Center (DLR) in Berlin and the Planetary Science Institute in Tuscon, Ariz.

Simulated Vesta from the South Pole
This image shows the scientists' best guess to date of what the surface of the protoplanet Vesta might look like from the south pole, as projected onto a sphere 250 kilometers (160 miles) in radius. It was created as part of an exercise for NASA's Dawn mission involving mission planners at NASA's Jet Propulsion Laboratory and science team members at the Planetary Science Institute in Tuscon, Ariz. Credit: NASA/JPL-Caltech/UCLA/PSI

“We won’t know what Vesta really looks like until Dawn gets there,” said Carol Raymond in a NASA statement. Raymond is Dawn’s deputy principal investigator, based at JPL, who helped orchestrate the activity. “But we needed a way to make sure our imaging plans would give us the best results possible. The products have proven that Dawn’s mapping techniques will reveal a detailed view of this world that we’ve never seen up close before.”

Two teams worked independently and used different techniques to derive the topographical maps from the available data sets. The final results showed only minor differences in spatial resolution and height accuracy.

Using the best available observations from the Hubble Space Telescope and ground based telescopes and computer modeling techniques, they created maps of still images and a rotating animation (below) showing their best guess as to what Vesta’s surface actually looks like. The maps include dimples, bulges and craters based on the accumulated data to simulate topography and thus give a sense of Virtual Vesta in three dimensions (3 D).

“Working through this exercise, the mission planners and the scientists learned that we could improve the overall accuracy of the topographic reconstruction, using a somewhat different observation geometry,” said Nick Mastrodemo, Dawn’s optical navigation lead at JPL. “Since then, Dawn science planners have worked to tweak the plans to implement the lessons of the exercise.”

Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer
Of course no one will know how close these educated guesses come to matching reality until Dawn arrives at Vesta.

The framing camera system consists of two identical cameras developed and built by the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany and the German Aerospace Center (DLR) in Berlin.

“The camera system is working flawlessly. The dry run was a complete success,” said Andreas Nathues, lead investigator for the framing camera at the Max Planck Institute in Katlenburg-Lindau, Germany.

Since the probe came out of hibernation, the mechanical and electrical components were checked out in mid March and found to be in excellent health and the software was updated.

Dawn is a mission of many firsts.

Dawn spacecraft under construction in Cleanroom.
Picture shows close up view of two science instruments;
The twin Framing Cameras at top (white rectangles) and VIR Spectrometer at right. Credit: Ken Kremer
The spacecraft is NASA’s first mission specifically to the Asteroid Belt. It will become the first mission to orbit two solar system bodies.

The revolutionary Dawn mission is powered by exotic ion propulsion which is vastly more efficient than chemical propulsion thrusters. Indeed the ability to orbit two bodies in one mission is only enabled via the use of the ion engines fueled by xenon gas.

Vesta and Ceres are very different worlds that orbit between Mars and Jupiter. Vesta is rocky and may have undergone volcanism whereas Ceres is icy and may even harbor a subsurface ocean conducive to life.

Dawn will be able to comparatively investigate both celestial bodies with the same set of science instruments and try to unlock the mysteries of the beginnings of our solar system and why they are so different.

Dawn is part of NASA’s Discovery program and was launched in September 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida.

Virtual Vesta in 2 D.
This image shows a model of the protoplanet Vesta, using scientists' best guess to date of what the surface of the protoplanet might look like. The images incorporate the best data on dimples and bulges of Vesta from ground-based telescopes and NASA's Hubble Space Telescope. The cratering and small-scale surface variations are computer-generated, based on the patterns seen on the Earth's moon, an inner solar system object with a surface appearance that may be similar to Vesta. Credit: NASA/JPL-Caltech/UCLA/PSI
Virtual Vesta in 3 D.
This anaglyph -- best viewed through red-blue glasses -- shows a 3-D model of the protoplanet Vesta, using scientists' best guess to date of what the surface of the protoplanet might look like. Image credit: NASA/JPL-Caltech/UCLA/PSI
Dawn Spacecraft current location approaching Asteroid Vesta on March 21, 2011
Posted on by Nancy Atkinson

Equipment to Study Hayabusa’s Asteroid Samples Damaged in Japan Earthquake

Magnified view of a dust particle in the Hayabusa canister. Credit: JAXA

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The large particle accelerator being used in to analyze the asteroid samples returned by the Hayabusa spacecraft was damaged by the March 11 earthquake in Japan, but the high energy accelerator at the KEK particle-physics laboratory will be repaired, according to this report on a Japanese website. An announcement on the KEK website said that all accelerators and experimental devices were stopped immediately “after the first shake” of the historic earthquake. “We have confirmed the radiation safety, and no hazard to the environment has been reported,” the announcement said. “Also there are no reports of casualties on both Tsukuba and Tokai campuses.” Tsukuba is in the mid-latitudes of Japan, about 50 km from Tokyo.

Apparently, the tiny asteroid particles are safe, but an official at KEK was quoted as saying (via Google Translate) “The accelerator needs to be adjusted very precisely. To suffer this much, but it takes time to recover, want to lose to the earthquake recovery.”

But the repairs to the accelerator may take a back seat to the current situation in Japan. The city of Tsukuba is going to take in refugees from Fukushima prefecture, where the heavily damaged nuclear reactor is located and the KEK facilities will provide support for radiation screening for the refugees upon their arrival.

This photo shows some of the damage to the Tsukuba Space Center in Tsukuba, Japan, the main space center for the country's JAXA agency, from the 8.9-magnitude earthquake that struck on March 11, 2011. Credit: collectSPACE.com

Tsukuba is also home to the space center that oversees Japan’s Kibo laboratory on the International Space Station, as well the JAXA’s unmanned cargo ships that deliver supplies on orbit. The space center was slightly damaged, and for awhile NASA’s Mission Control in Houston took over operations remotely. According to Robert Pearlman on collectSPACE, several of the Japanese flight control team members and flight directors from the Tsukuba Space Center happened to be in Houston when the quake struck, preparing for the Expedition 27 crew rotation, as astronaut Satoshi Furukawa will be heading the ISS in May. However, operations from the mission control rooms were resumed at 4:00 p.m. on March 22, 2011.

JAXA Flight Control Team (JFCT) resuming the Kibo operations at the Mission Control Room (MCR). Credit: JAXA

Another center, the Kakuda Space Center, located in the Miyagi region close to the most serious effects of the earthquake and tsunami, was heavily damaged, and is closed with no timetable for reopening. The Kakuda center is JAXA’s rocket development and testing center and is Japan’s equivalent of the Stennis Space Center in Mississippi.

JAXA’s Tsukuba Space Center located in Tsukuba Science City,

Additionally, the ground-breaking ceremony for a new type of particle smasher known as a “super B factory” in Tsukuba has been postponed. Japan had invested $100 million to transform the KEKB collider in Tsukuba, into a Super KEKB, which will smash electrons into positrons at 40 times the rate of the current accelerator.
Just before the quake, the Japanese Space Agency JAXA had announced they are planning a second Hayabusa mission with an explosive twist. The second mission to an asteroid probe will include an impactor that detonates an explosive on the asteroid’s surface, similar to the Deep Impact mission.

The launch was tentatively planned for launch in 2014, heading to a space rock catalogued as 162173 1999 JU3. The probe would land on the surface and, collect samples before and after the impactor blasts its way to the asteroid’s interior.

Despite the problems Hayabusa encountered along its arduous journey to and from asteroid Itokawa –including thruster, communications, gyro and fuel-leak problems, as well as uncertainty whether the probe landed on the asteroid – JAXA and the Japanese people were buoyed by the success of Hayabusa.

It is not clear how the tragic earthquake and tsunami will affect future space missions for Japan, but obviously the country has more important issues ahead of them. May the spirit of the Japanese people be lifted again.

Sources: NHK,, KEK , collectSPACE, Moon and Back, JAXA

Hat tip to Emily Lakdawalla via Twitter.

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.