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Asteroid Itokawa Sample Return #Hayabusa

Asteroid Itokawa Sample Return

 

Dec. 29, 2010:  The Japanese Aerospace Exploration Agency's Hayabusa spacecraft has brought home to Earth tiny pieces of an alien world–asteroid Itokawa.

"It's an incredible feeling to have another world right in the palm of your hand," says Mike Zolensky, Associate Curator for Interplanetary Dust at the Johnson Space Center, and one of the three non-Japanese members of the science team. "We're seeing for the first time, up close, what an asteroid is actually made of!"

Sample Return (shadow, 550px)
Hayabusa photographs its own shadow on asteroid Itokawa in 2005 prior to collecting samples from the big space rock. [more]

He has good reason to be excited. Asteroids formed at the dawn of our solar system, so studying these samples can teach us how it formed and evolved.

Hayabusa launched in 2003 and set out on a billion kilometer voyage to Itokawa, arriving a little over two years later. In 2005, the spacecraft performed a spectacular feat -- landed on the asteroid's surface(1). The hope was to capture samples from the alien world.

But there was a problem. The projectiles set to blast up dust from the surface failed to fire, leaving only the particles kicked up from landing for collection. Did any asteroid dust made it into the collection chamber?

Sample Return (descent diagram, 200px)
The return of Hayabusa went exactly according to plan, according to JAXA:full story.

Zolensky and other eager scientists, with eyes riveted skyward, watched the answer plunge back into Earth's atmosphere at 27,000 miles per hour on the night of June 13th, 2010. Hayabusa's main bus shattered over the Australian outback during reentry, and the intact sample return capsule drifted to Earth via parachute.

"We were mesmerized," says Zolensky. "As we waited for it to land, no one even moved."

But the waiting was only just beginning. Because attempting retrieval of the capsule in the dark was too dangerous, he spent a sleepless night before getting a closer look.

"I was one of the first people to board the helicopter that flew to the landing site the next morning. And I was the first person to walk up to the capsule."

He had to stop within 10 feet of it. More waiting.

"I watched the retrieval team recover it. They wore face masks and gloves and blue padded suits. They had to disable the unexploded parachute release charges, and that was pretty nerve wracking. Then they picked up the capsule oh so carefully and placed it in a box."

The precious cargo was flown via charter jet to Japan for analysis. Guess who was waiting for it when it arrived?

"I was ready to work," says Zolensky, who along with fellow team member Scott Sandford of NASA Ames Research Center had traveled to Japan for the opening.

"The first results were disheartening. When we scanned the capsule with a modified CAT scan, there appeared to be nothing inside."

Next, Japanese members of the team painstakingly dismantled the capsule, piece by piece. "They had to use a micromanipulator to avoid contamination, and the process took months."

More waiting.

Sample Return (particles, 550px)
Electron microscope photos of material found inside Hayabusa's sample return container. Red arrows point to particles from the asteroid. [more]

"Once we got inside the capsule, we could see dust on the interior walls. I thought to myself, 'we've got asteroid dust here!' But there was still a possibility the contents could be contamination from launch or reentry and landing."

The next step was to remove and analyze the particles -- another agonizingly slow process, and more waiting.

"The particles are each smaller than the diameter of a human hair. We finally used a Teflon spatula to sweep out a large number of tiny particles."

Though most of the particles are still in the capsule, the team has removed and analyzed 2000 of them with an electron microscope.

And?

"At least 1500 of them are from the asteroid! We're seeing pieces of another world. It looks like a very primitive type asteroid. We'll tell you more in March at the 2011 Lunar and Planetary Science Conference in Houston."

This is only the third time ever that samples of a solid extraterrestrial body have been brought back to Earth. The Apollo astronauts and Soviet Luna robots were first – they brought us samples of moondust. And NASA's Stardust spacecraft returned samples of comet Wild 2 in 2006.

"The Japanese people are thrilled, and so are we. The emperor even requested a personal tour of the capsule. This is their Apollo mission. They're showing us all a new world!"


Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA

 

 

For More Information

Web Links:

Asteroid Explorer Hayabusa -- JAXA mission home page

Identification of origin of particles brought back by Hayabusa -- JAXA press release

Bringing Hayabusa Back to Earth -- JAXA feature story

End Notes:

(1) This is only the second time an asteroid landing has been achieved. The only other time in history a spacecraft landed on an asteroid's surface was when NASA’s Near Earth Asteroid Rendezvous-Shoemaker spacecraft landed on asteroid Eros in February 2001.

 

 

#Hubble Sees Suspected Asteroid Collision - #NASA

Hubble Sees Suspected Asteroid Collision

02.02.2010

February 2, 2010: NASA's Hubble Space Telescope has observed a mysterious X-shaped debris pattern and trailing streamers of dust that suggest a head-on collision between two asteroids. Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never been seen before.

The object, called P/2010 A2, was discovered by the Lincoln Near-Earth Asteroid Research (LINEAR) sky survey on Jan. 6. At first, astronomers thought it might be a so-called "main belt comet"--a rare case of a comet orbiting in the asteroid belt. Follow-up images taken by Hubble on Jan. 25 and 29, however, revealed a complex X-pattern of filamentary structures near the nucleus:

"This is quite different from the smooth dust envelopes of normal comets," says principal investigator David Jewitt of the University of California at Los Angeles. "The filaments are made of dust and gravel, presumably recently thrown out of the nucleus. Some are swept back by radiation pressure from sunlight to create straight dust streaks. Embedded in the filaments are co-moving blobs of dust that likely originated from tiny unseen parent bodies."
Hubble shows the main nucleus of P/2010 A2 lies outside its own halo of dust. This has never been seen before in a comet-like object. The nucleus is estimated to be 460 feet in diameter.

Normal comets fall into the inner regions of the solar system from icy reservoirs in the distant Kuiper belt and Oort cloud. As comets approach the sun and warm up, ice near the surface vaporizes and ejects material from the solid comet nucleus via jets. But P/2010 A2 may have a different origin. It orbits in the warm, inner regions of the asteroid belt where its nearest neighbors are dry rocky bodies lacking volatile materials.

This leaves open the possibility that the complex debris tail is the result of an impact between two bodies, rather than ice simply melting from a parent body.

"If this interpretation is correct, two small and previously unknown asteroids recently collided, creating a shower of debris that is being swept back into a tail from the collision site by the pressure of sunlight," Jewitt says.

Asteroid collisions are energetic, with an average impact speed of more than 11,000 miles per hour--five times faster than a rifle bullet. The main nucleus of P/2010 A2 would be the surviving remnant of this so-called hypervelocity collision.

Right: A full-context view of P/2010 A2. Credit: NASA, ESA, and D. Jewitt (University of California, Los Angeles). Photo No. STScI-2010-07 [larger image]

"The filamentary appearance of P/2010 A2 is different from anything seen in Hubble images of normal comets, consistent with the action of a different process," Jewitt says. An impact origin also would be consistent with the absence of gas in spectra recorded using ground-based telescopes.

The asteroid belt contains abundant evidence of ancient collisions that have shattered precursor bodies into fragments. The orbit of P/2010 A2 is consistent with membership in the Flora asteroid family, produced by collisional shattering more than 100 million years ago. One fragment of that ancient smashup may have struck Earth 65 million years ago, triggering a mass extinction that wiped out the dinosaurs. But no such asteroid-asteroid collision has been caught "in the act"--until now.

At the time of the Hubble observations, the object was approximately 180 million miles from the sun and 90 million miles from Earth. The Hubble images were recorded with the new Wide Field Camera 3 (WFC3).

Editor: james.a.phillips@earthlink.net"> Dr. Tony Phillips | Credit: Science@NASA

via science.nasa.gov

The Hubble Space Telescope has shown us many beautiful images over the years and provided us with exciting space walks and repair projects too. The observation of predicted asteroid collisions in the asteroid belt has got to be among Hubble's greatest observations.

@dmgerbino

Asteroid Explodes Over Indonesia - SpaceWeather.com -- WoW!

INDONESIAN ASTEROID: Picture this: A 10-meter wide asteroid hits Earth and explodes in the atmosphere with the energy of a small atomic bomb. Frightened by thunderous sounds and shaking walls, people rush out of their homes, thinking that an earthquake is in progress. All they see is a twisting trail of debris in the mid-day sky:


Click to view an Indonesian news report

This really happened on Oct. 8th around 11 am local time in the coastal town of Bone, Indonesia. The Earth-shaking blast received remarkably little coverage in Western press, but meteor scientists have given it their full attention. "The explosion triggered infrasound sensors of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) more than 10,000 km away," report researchers Elizabeth Silber and Peter Brown of the Univ. of Western Ontario in an Oct. 19th press release. Their analysis of the infrasound data revealed an explosion at coordinates 4.5S, 120E (close to Bone) with a yield of about 50 kton of TNT. That's two to three times more powerful than World War II-era atomic bombs.

The asteroid that caused the blast was not known before it hit and took astronomers completely by surprise. According to statistical studies of the near-Earth asteroid population, such objects are expected to collide with Earth on average every 2 to 12 years. "Follow-on observations from other instruments or ground recovery efforts would be very valuable in further refining this unique event," say Silber and Brown.

via spaceweather.com

This is so amazing! I just had to share this story.