Water on the Moon and Much, Much More: Latest LCROSS Results

An image of debris, ejected from Cabeus crater and into the sunlight, about 20 seconds after the LCROSS impact. The inset shows a close-up with the direction of the sun and the Earth. Image courtesy of Science/AAAS

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A year ago, NASA successfully slammed a spent Centaur rocket into Cabeus Crater, a permanently shadowed region at the lunar South Pole. The “shepherding” LCROSS (Lunar Crater Observation and Sensing Satellite) spacecraft followed close on the impactor’s heels, monitoring the resulting ejecta cloud to see what materials could be found inside this dark, unstudied region of the Moon. Today, the LCROSS team released the most recent findings from their year-long analysis, and principal investigator Tony Colaprete told Universe Today that LCROSS found water and much, much more. “The ‘much more’ is actually as interesting as the water,” he said, “but the combination of water and the various volatiles we saw is even more interesting — and puzzling.”

The 2400 kg (5200 pound) Centaur rocket created a crater about 25 to 30 meters wide, and the LCROSS team estimates that somewhere between 4,000 kilograms (8,818 pounds) to 6,000 kilograms (13,228 pounds) of debris was blown out of the dark crater and into the sunlit LCROSS field of view. The impact created both a low angle and a high angle ejecta cloud. (Read more about the unusual plume in our interview with LCROSS’s Pete Schultz).

The LCROSS team was able to measure a substantial amount of water and found it in several forms. “We measured it in water vapor,” Colaprete said, “and much more importantly in my mind, we measured it in water ice. Ice is really important because it talks about certain levels of concentration.”

With a combination of near-infrared, ultraviolet and visible spectrometers onboard the shepherding spacecraft, LCROSS found about 155 kilograms (342 pounds) of water vapor and water ice were blown out of crater and detected by LCROSS. From that, Colaprete and his team estimate that approximately 5.6 percent of the total mass inside Cabeus crater (plus or minus 2.9 percent) could be attributed to water ice alone.

Colaprete said finding ice in concentrations – “blocks” of ice — is extremely important. “It means there has to be some kind of process by which it is being enhanced, enriched and concentrated so that you have what is called a critical cluster that allows germ formation and crystalline growth and condensation of ice. So that data point is important because now we have to ask that question, how did it become ice?” he said.

In with the water vapor, the LCROSS team also saw two ‘flavors’ of hydroxyl. “We saw one that was emitting as it if it was just being excited,” Colaprete said, “which means this OH could have come from grains — it could be the adsorbed OH we saw in the M Cubed data, as it was released or liberated from a hot impact and coming up into view. We also see an emission from OH that is called prompt emission, which is unique to the emission you get when OH is formed through photolysis.”

Then came the ‘much more.’ Between the LCROSS instruments, the Lunar Reconnaissance Orbiter’s observations – and in particular the LAMP instrument (Lyman Alpha Mapping Project) – the most abundant volatile in terms of total mass was carbon monoxide, then was water, the hydrogen sulfide. Then was carbon dioxide, sulfur dioxide, methane, formaldehyde, perhaps ethylene, ammonia, and even mercury and silver.

“So there’s a variety of different species, and what is interesting is that a number of those species are common to water,” Colaprete said. “So for example the ammonia and methane are at concentrations relative to the total water mass we saw, similar to what you would see in a comet.”

The LCROSS NIR spectrometer field of view (green circle), projected against the target area in the crater Cabeus. Credit: Colaprete, et al.

Colaprete said the fact that they see carbon monoxide as more abundant than water and that hydrogen sulfide exists as a significant fraction of the total water, suggests a considerable amount of processing within the crater itself.

“There is likely chemistry occurring on the grains in the dark crater,” he explained. “That is interesting because how do you get chemistry going on at 40 to 50 degrees Kelvin with no sunlight? What is the energy — is it cosmic rays, solar wind protons working their way in, is it other electrical potentials associated with the dark and light regions? We don’t know. So this is, again, a circumstance where we have some data that doesn’t make entirely a lot of sense, but it does match certain findings elsewhere, meaning it does look cometary in some extent, and does look like what we see in cold grain processes in interstellar space.”

Colaprete said that finding many of these compounds came as a surprise, such as the carbon monoxide, mercury, and particularly methane and molecular hydrogen. “We have a lot of questions because of the appearance of these species, “ he said.

There were also differences in the abundances of all the species over the time – the short 4 minutes of time when they were able to monitor the ejecta cloud before the shepherding spacecraft itself impacted the Moon. “We actually can de-convolve, if you will, the release of the volatiles as a function of time as we look more and more closely at the data,” he said. “And this is important because we can relate what was released at the initial impact, what was released as grains sublimed in sunlight, and what was “sweated out” of the hot crater. So that’s where we’re at right now, it’s not just, ‘hey we saw water, and we saw a significant amount.’ But as a function of time there are different parts coming out, and different ‘flavors’ of water, so we are unraveling it to a finer and finer detail. That is important, since we need to understand more accurately what we actually impacted into. That is really what we are interested in, is what are the conditions we impacted into, and how is the water distributed in the soil in that dark crater.”

So the big question is, how did all these different compounds get there? Cometary impacts seem to offer the best answer, but it could also be outgassing from the early Moon, solar wind delivery, another unknown process, or a combination.

“We don’t understand it at all, really,” Colaprete said. “The analysis and the modeling is really in its infancy. It is just beginning, and now we finally have some data from all these various missions to constrain the models and really allow us to move beyond speculation.”

LCROSS was an “add-on” mission to the LRO launch, and the mission had several unknowns. Colaprete said his biggest fear going into the impact and going into the results was that they wouldn’t get any data. “I had fears that something would happen, there would be no ejecta, no vapor and we’d just disappear into this black hole,” he confessed. “And that would have been unfortunate, even though it would have been a data point and we would have had to figure out how the heck that would happen.”

But they did get data, and in an abundance that — like any successful mission — offers more questions than answers. “It really was exploration,” Colaprete said. “We were going somewhere we had absolutely never gone before, a permanently shadowed crater in the poles of the Moon, so we knew going into this that whatever we got back data-wise would probably leave us scratching our heads.”

Additional source: Science

STS-133 Crew Conducts TCDT Training

The crew of STS-133 discusses their perspectives on the final flight of space shuttle Discovery with the media. Photo Credit: Universe Today/awaltersphoto.com

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The crew for the last mission for space shuttle Discovery spent the week at NASA’s Kennedy Space Center conducting the Terminal Countdown Demonstration Test or as it is more commonly know – TCDT. The crew arrived Tuesday, Oct. 12 and immediately set to work. This week of training is the last major milestone on the path to launch, currently scheduled to take place on Nov. 1 at 4:40 p.m. EDT.

TCDT consists of is training that simulates the final hours up until launch. This provides training for both the crew and the launch team. The launch team practices launch day timelines as well other, crucial flight-day procedures. The crew on the other hand went through a number of exercises that included:

• Rescue training – The astronauts will run through several simulations where they practice what to do in the event of an emergency. The crew will be instructed on how to use the emergency baskets that will allow them to escape the launch pad in case there is a fire. They will also learn how to operate the tank-like M113 personnel carrier and other emergency equipment.
• The commander in pilot will perform abort landings and other flight aspects in the Shuttle Training Aircraft (STA). The plane is a Grumman Gulfstream II and it duplicates the shuttle’s approach profile and many of the orbiter’s handling qualities.
• Conduct a launch day simulation that includes everything that will happen on launch day – except the launch. The crew walked out in their bright orange launch and entry suits. TCDT also includes a simulated abort so that the crew is well-versed as to what do to in case of that scenario.

STS-133 crew members arrive at NASA's Kennedy Space Center in their sleek T-38 jets. Photo Credit: Universe Today/awaltersphoto.com

These activities allow the crew and flight teams to do a rehearsal of all the events that will take place on launch day.

“This is a dress rehearsal for the real flight so the crew is kind of peaked up; they’ve put all the sequence of events together, when they go out to the pad they’ll do everything except igniting the main engines,” said Robert Springer a two-time shuttle veteran. “It’s a chance to review all your procedures and make sure everything is in place.”

The crew of STS-133 consists of Lindsey, Pilot Eric Boe and Mission Specialists, Michael Barratt, Tim Kopra, Alvin Drew and Nicole Stott. The crew is comprised entirely of space flight veterans.

NASA's official crew portrait of the crew of STS-133. Image Credit: NASA
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STS-133 is an 11-day mission to the International Space Station (ISS) to deliver the Leonardo Permanent Multipurpose Module (PMM) which contains, among other thing, the first humanoid robot to fly into space – Robonaut-2 (R2). Also onboard is the Express Logistics Carrier-4 and spare parts for the orbiting laboratory.

Springer’s first flight was on space shuttle Discovery and as he watched the crew for her final mission his thoughts reflected on his experiences and the end of the shuttle era.

“It’s going to be a little tough, my personal experiences that I have of Discovery and my memories that I have of that time make it a little bittersweet to realize that this will be the last time that Discovery will go into space.”

More Recent Landslides Spotted on Mars

Recent Landslide in Zunil Crater on Mars. Credit: NASA/JPL/University of Arizona

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Thanks to the Mars Reconnaisance Orbiter and the on-board HiRISE camera, scientists are able to monitor Mars for changes taking place on the landscape. They do this by comparing older images with newer ones, and also by seeing “fresh” features — like this recent landslide in Zunil Crater. “The color and albedo patterns indicate that a landslide occurred here very recently–too recently to have been re-covered by dust,” writes Alfred McEwen, principal investigator of HiRISE, writing on the camera’s website. “Looking for changes such as this will help us to better understand active processes.” McEwen said the landslide could have been triggered by a Marsquake or a small impact event.”

See more recent landslides below:

This landslide was spotted by Stu Atkinson; boulders and debris are below a steep north polar boundary scarp. Credit: NASA/JPL/University of Arizona

Our ‘eagle-eyed’ pal Stuart Atkinson found this landslide on a steep scarp in the north polar region. It looks as though a lot of rock has fallen from the cliff, and discussion among other image artists on UnmannedSpaceflight.com indicated that the blue areas could easily be patches of ice deposited from the cliff face. You can see the original image at the HiRISE website.

Frosted Gullies in the Northern Summer. Credit: NASA/JPL/University of Arizona

This image is so amazing, in that from orbit, we are looking down the side of a crater wall, where gullies have formed. There are two schools of thought on these types of gullies: one, many scientists believe that these gullies have been carved by liquid water, and were carved recently, so this recent, present-day activity is of immense interest.

A second opinion is that accumulations of frost in the gully alcoves starts an avalanche of loose material that does not involve liquid water. The MRO scientists will continue to analyze many images like this in order to try and answer the broader question of whether liquid water is responsible for the the gullies, landslides and avalanches or not.

andslides along the Walls of Bahram Vallis. Credit: NASA/JPL/University of Arizona

This image of Bahram Vallis has large mounds of material at the base of the valley floor. These deposits of material have the characteristic shape of rotational landslides or slumps on Earth where material along the entire wall slumps down and piles debris at the base of the slope, “much like a person who slumps down the back of a chair,” writes Frank Chuang from the HiRISE team. “Right at the cliff edge at the top of the slope, the shape of the area where the valley wall gave way to a landslide is not straight, but rather curved or semi-circular. This is typical of large landslides where the failure area has an arcuate “crown” shape. The fact that landslides have occurred here indicates that the valley walls are not stable and the materials respond to Martian gravity with mass movements.”

See more images at the HiRISE website.

Is the World Ready for An Asteroid Threat? Apollo’s Schweickart Pushes for Action

Computer generated simulation of an asteroid strike on the Earth. Credit: Don Davis/AFP/Getty Images

If we discover an asteroid heading directly towards Earth, are we ready to deal with the challenges of either deflection strategies or an evacuation prior to impact? Apollo 9 astronaut Rusty Schweickart has spent years championing the need for the human race to prepare for what will certainly happen one day: an asteroid threat to Earth. Schweickart is Chairman of the Board of the B612 Foundation, a non-profit private foundation that supports the development and testing of a spaceflight concept to protect the Earth from future asteroid impacts, and he says we have the technology today to deal with it, but nothing has been verified or tested. “We need to mobilize that technology and achieve an international consensus on what actions should be taken,” he told Universe Today.

Schweickart also co-chairs — with another former astronaut, Tom Jones — the Planetary Defense Task Force of the NASA Advisory Council. On October 6, 2010, the Task Force submitted a list of five recommendations to the Council to suggest how NASA should organize, investigate, prepare, and lead national and international efforts defending our planet from an asteroid impact.

Rusty Schweickart

“Our report and recommendations are a necessary, but not sufficient element of a sequence of actions which hopefully will lead to humanity being able to prevent future asteroid impacts with Earth,” Schweickart explained. “Assuming positive action by OSTP (Office of Science and Technology Policy) and the Congress, we’ll be well on our way to preventing future impact disasters.”

The report stresses that NASA should significantly improve the ability to discover and track potential NEO impactors to allow for early detection, develop effective impact mitigation techniques, and prepare an adequate response to the range of potential impact scenarios.

These recommendations have been approved by the Advisory Council, and the report was submitted to the NASA Administrator. Then, the Office of Science and Technology Policy (OSTP) is supposed to make a decision by tomorrow – Friday, October 15, 2010 –to make assignments in the US government as to what the breakdown of work should be to protect the Earth from an asteroid impact.

Among the recommendations in the PDTF report is developing mitigation techniques. But could NASA do this type of work within their new budget? “People intuitively think that if you’re going to be pushing asteroids around, that work will take over NASA,” said Schweickart said in a phone interview with Universe Today . “Wrong. It would be a ripple in NASA’s budget, a pimple, 1.5-2.0 percent at the most of NASA’s annual budget for 10 years then dropping back to less than 0.5%. It does not displace anything else that NASA is doing. It would be a small budgetary issue, but the importance of it is huge. This saves lives, protects the global environment, and saves future generations.”

*Update (10/16/10) Schweickart asked to add to his comments about budgetary needs, as there were some misinterpretations. “I certainly did not intend that it be interpreted as no budget increment is needed! In fact our report makes very clear that we strongly recommend that Congress increment the existing budget for this purpose and not take it out of existing programs. It is not costly, but other NASA programs should not be penalized in order to support a responsible, public safety program which would amount to only a 1.5-2.0% increment in the NASA budget.”

Artist concept of a space tug. Credit: NASA

The technology needed exists today, Schweickart said, “that is, we do not have to go into a big technology development program in order to deflect most asteroids that would pose a threat of impact. However, that technology has not been put together in a system design, and not been verified, tested or demonstrated that it could actually deflect an asteroid. So, we need to test everything – test the very sequence we would use for a deflection campaign.”

The best way to test it would be to have NASA, or perhaps a consortium of space agencies, carry out an actual mission to test the entire system.

“Not with an asteroid that threatens an impact,” said Schweickart, “but with an asteroid that is just minding its own business, and we’d have the opportunity to show we can change its orbit slightly in a controlled way.”

The crew of Apollo 9: Commander James McDivitt, Command Module Pilot Dave Scott and Lunar Module Pilot Rusty Schweickart. Credit: NASA

Schweickart said the B612 foundation, and the Association of Space Explorers (ASE; the professional organization of astronauts and cosmonauts from around the world) and every planetary defense conference held recently has discussed the need for such a capability validation.

But the recommendations made by the PDTF are, for now just suggestions, and certainly not a mandate for NASA to prepare in a meaningful way for an asteroid threat.

“There’s no official design of a deflection mission because there is no responsibility to do it,” Schweickart said. “Right now, NASA’s assignment is only to find these asteroids. Period. That’s it.”

But, with the October 15 deadline almost here, Schweickart is hopeful. “Hopefully, that will begin the process of NASA actually having this responsibility,” he said, “and that Congress will respect that and a budget be allocated in order to do the job. Then mission planners can start designing demonstration missions.”

However, if the past is any indication, any mandate wouldn’t necessarily mean a mission would happen soon.

The Pan-STARRS telescope on Haleakala, Hawaii. Photograph by Rob Ratkowski for the PS1SC

Congress directed NASA to do the “Spaceguard” survey to find all asteroids around 40 meters and larger by 2020. “To come close to achieving that, we need to have new telescopes that will have greater capabilities than what we’ve been using to date,” said Schweickart. “Right now the Pan-STARRS telescope has the equivalent of one eye squinting, and it is not exactly knocking everybody’s socks off. LSST (Large Synoptic Survey Telescope) is still hundreds of millions of dollars before being a fully funded project.”

Schweickart said the Task Force heard presentations on perhaps better ways to complete that Congressional goal and their report indicates that at least 87% of the large asteroids whose impacts could pose a global threat to our civilization have been discovered. Right now, none pose a credible threat of a collision with Earth for the foreseeable future. But the discovery rate of the much more numerous smaller NEOs, — which represent a regional or local impact hazard — “will soon confront us with objects presenting worrisome but uncertain probabilities for a future collision with Earth. Such situations will appear more frequently as the discovery rate increases, and the nation presently has no clear policy on how to address such a situation,” the report says.

“Congress’s favorite thing to do is to tell you to do something and not give you any money for it,” Schweickart said. “That is not very responsible and it doesn’t always work and it’s not the right way a government should operate, especially where public safety is at issue. Therefore it is important that the OSTP lead the way on this issue on October 15.”

Tomorrow: What would an asteroid deflection campaign entail?

For more information:
B612 Foundation

Planetary Defense Task Force of the NASA Advisory Council

Office of Science and Technology Policy

Pan-STARRS

Large Synoptic Survey Telescope

‘Secret’ X-37B Space Plane Disappears Again

Artist impression of the Boeing X-37B (USAF)

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The game between the United States Air Force and amateur satellite trackers continues: the unmanned X-37B space plane – a classified project of the Air Force – has changed orbit once again, leaving those that monitor the flyovers of the space plane scrambling to locate it once again.

The X-37B was launched on April 22nd, 2010 on an Atlas V rocket from Cape Canaveral, Florida, and has been orbiting the Earth ever since. During the period between July 29th and August 14th of this year, the plane changed its orbit and forced the amateurs that monitor the satellite to find it again, and recalculate its orbital path. According to Spaceweather.com yesterday, the X-37B has once again changed its location. It did not pass over at the expected time on the nights of October 7th and October 9th.

Possibilities for this latest change in orbit include a simple maneuvering test or change in the current testing phase of the plane, or the potential that it is finally about to land. The gallium arsenide solar panels on the craft should allow it to stay in space for up to 270 days, but it has only been 173 days since the launch.

The X-37B is controlled remotely, and can automatically land. Once this flight is over, it will land at either the Vandenberg Air Force Base or the Edwards Air Force Base, both located in California.

Not much has been said about the the secret project by the Air Force. Started at NASA in 1999, the automated space plane was handed over to the Pentagon in 2004. This initial flight of the X-37B is billed as a test of the craft by the Air Force. Here’s its description according to the Air Force fact sheet:

“The X-37B Orbital Test Vehicle, or OTV, is a non-operational system that will demonstrate a reliable, reusable, unmanned space test platform for the U.S. Air Force. The objectives of the OTV program include space experimentation, risk reduction and a concept of operations development for reusable space vehicle technologies.”

Of course, there has been much speculation about whether this constitutes the “weaponization of space”, since it is, after all, a project of the Air Force instead of NASA. To put your mind at ease, here’s a link to an analysis of potential uses of the X-37B by former Air Force officer Brian Wheeden, who is now a Technical Adviser to the Secure World Foundation. He places the likelihood that the space plane could be used as a weapon at zero, but its capabilities as an orbital spy platform are feasible.

If you want a comprehensive look into the history and the possible uses of the X-37B, there is a lengthy article over at Air & Space by associate editor Michael Klesius.

There’s also a video up on Space.com by satellite tracker Kevin Fetter of Brockville, Ontario showing a flyover of the plane.

We’ll keep you posted as to when the X-37B is recovered by amateurs, if it has landed, or in the unlikely event that the Air Force decides to release any information about its current mission.

Source: Spaceweather.com

JAXA: Hayabusa Capsule Contains Particles, Maybe of Asteroid

Artist concept of the Hayabusa spacecraft, which visited asteroid Itokawa in 2005 and returned samples to Earth in 2010. Credit: JAXA
Artist concept of the Hayabusa spacecraft, which visited asteroid Itokawa in 2005 and returned samples to Earth in 2010. Credit: JAXA

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At a press conference yesterday, officials from the Japan Aerospace Exploration Agency (JAXA) announced that they had “scraped up” a hundred or so particles of dust, perhaps grains of dust from the asteroid, Itokawa, inside the sample return capsule of the Hayabusa spacecraft. This is great news, as previous reports from JAXA indicated they weren’t sure if there were any particles at all inside the container. Originally, the mission had hoped to bring back “peanut-sized” asteroid samples, but the device that was supposed to fire pellets at the asteroid may not have worked, and for a time, scientists were even unsure if the spacecraft had even touched down on the asteroid.

During the seven-year round trip journey, Hayabusa arrived at Itokawa in November, 2005. After a circuitous and troubled-filled return trip home, the sample return capsule was ejected and landed in Australia in June of this year.

The 100 or so grains reported yesterday are extremely tiny, and the micron-sized particles were scraped off the sides of container and are now being examined with an electron microscope. They don’t appear to be metallic, so are not fragments from the container, but they don’t have absolute proof yet that the particles are from the asteroid.

Soon, the grains will be examined using particle accelerator/synchrotron. Additionally, some reports indicated there is another yet unopened compartment that will be examined soon.

A little surfing of the net (in all languages) reveals there are tons of news articles out there reporting this. The only problem is that some of these news reports called the potential asteroid particles “extraterrestrial,” which then became translated as “extraterrestrial life” in the next article in another language. Ah, the wonders of the internet!

We’ll keep you posted!

Comet Hartley 2 Scouted by WISE, Hubble for Upcoming Encounter

This image of Hartley 2 - Deep Impact's next cometary target - was taken on Sept. 25th by the Hubble Space Telescope. Image Credit: NASA, ESA, H. Weaver (The Johns Hopkins University/Applied Physics Lab)

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In a little less than a month, NASA’s Deep Impact spacecraft (its current mission is called EPOXI) will fly by the comet Hartley 2 to image the comet’s nucleus and take other measurements. In preparation for this event, both the Wide-field Infrared Survey Explorer (WISE) and the Hubble Space Telescope have imaged the comet, scouting out the destination for Deep Impact.

On November 4th of this year, Deep Impact will come within 435 miles (700 km) of the comet Hartley 2, close enough to take images of the comet’s nucleus.

The name of the mission is EPOXI, which is a combination of the names for the two separate missions the spacecraft has been most recently tasked with: the extrasolar planet observations, called Extrasolar Planet Observations and Characterization (EPOCh), and the flyby of comet Hartley 2, called the Deep Impact Extended Investigation (DIXI). The spacecraft itself is still referred to as Deep Impact, though, despite the changes and extensions of its mission.

NASA’s Deep Impact mission to slam a copper weight into comet Tempel 1 was a wonderful success, sending back data that greatly improved our understanding of the composition of comets. After the encounter, though, there was still a lot of life left in the spacecraft, so it was tasked with another cometary confrontation: take images of the comet Hartley 2.

Deep Impact is an example of NASA using a single spacecraft to perform multiple, disparate missions. In addition to impacting and imaging Tempel 1 and performing a flyby of Hartley 2, the spacecraft took observations of 5 different stars outside of our Solar System during the period between January and August of 2008 (8 were scheduled, but some observations were missed due to technical difficulties).

It looked at stars with known exoplanets to observe transits of those planets in front of the star, giving astronomers a better idea of the orbital period, albedo – or reflectivity – and size of the planets.

Click here for a list of the various stars and transits it observed, as listed on the mission page.

Deep Impact also took data on both the Earth and Mars as they passed in front of our own Sun, to help characterize what exoplanets with a similar size and composition the Earth and Mars would look like passing in front of a star.

NASA's WISE infrared observatory took this image of Hartley 2, showing the extent of its tail, on May 10th, 2010. Image Credit: NASA/JPL-Caltech/UCLA

As of September 29th, Deep Impact was about 23 million miles (37 million km) away from Hartley 2. It is approaching at roughly 607,000 miles a day (976,000 km), so that puts it at about 18 million miles (29 million km) away from the comet today. As it approaches, Deep Impact will speed up, to over 620,000 miles (1,000,000 km) per day.

The path of Comet Hartley 2. Image courtesy Sky & Telescope.

You won’t have to depend on NASA’s observatories and the spacecraft to see a view of Hartley 2, though – you should be able to see it with the naked eye or binoculars near the constellation Perseus throughout the month of October. On October 20th, it will make its closest approach to Earth at a distance of 11 million miles (17.7 million km). The comet is officially designated 103P Hartley, and for viewing information you can go to Heavens Above.

As always, check this space regularly for updates on the upcoming flyby.

Sources: JPL here, here and here, Hubblesite, Heavens Above

Rosetta Uncovers a Thick, Dusty Blanket on Lutetia

An image taken by the Rosetta spacecraft on its closest approach to 21-Lutetia in July. Recent analysis of the data shows a thick, dusty blanket coating the asteroid. Image Credit:ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

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If you think that asteroids are boring, unchanging rocks floating in space waiting only to crop up in bad science fiction films, think again. Images and data that are being returned from various asteroid flybys – such as those by the Rosetta spacecraft and Hayabusa sample return mission – show that asteroids are dynamic, changing miniature worlds unto themselves.

During the recent flyby of the asteroid 21-Lutetia in July, the ESA’s Rosetta spacecraft took an amazing amount of data. After combing through all of this data over the past few months, astronomers have calculated that the asteroid is covered in a 2000-foot (600 meter)-thick blanket of rocks and dust called regolith. This dust is not unlike the outer layer of the Earth’s Moon, consisting of pulverized material that has accumulated over billions of years.

Rosetta is on a course to meet up with the comet 67P/Churyumov-Gerasimenko in 2014, but the spacecraft is no stranger to asteroid visits – on September 6th, 2008, Rosetta made its closest approach of the asteroid 2867-Steins. During this brief visit, Rosetta came within 500 miles (800km) of the small, diamond-shaped asteroid. Among the discoveries made were a chain of impact craters that were likely caused by the collision with a meteoroid stream, or the impact with another small body.

It then approached 21-Lutetia on July 10th of 2010, monitoring the asteroid with 17 instruments on board the spacecraft.

Rosetta took a number of images of the flyby, as well as examining the asteroid with electromagnetic detectors that covered the gamut from the UV to radio waves. Here’s a short animation showing the flyby:

Dr. Rita Schulz from the ESA Research and Scientific Support Department in the Netherlands presented this new information about 21-Lutetia’s regolith today at the Division for Planetary Sciences meeting in Pasadena, CA. She said that the regolith on the asteroid has been determined to be about 2000 feet (600 meters) thick, and that it resembles the regolith on the Moon. Images from the flyby reveal landslides, boulders, ridges, and other kinds of different geologic (or asterologic?) features.

21-Lutetia was determined by the July flyby to have a large, bowl-shaped impact crater on its surface, as well as an abundance of smaller craters. The thick covering of dust “softens” the sharper edges of impact craters in many of the images taken. Whether or not most asteroids of this size are covered in a similar blanket of material remains to be seen.

Boulders can be seen in this close-up image of 21-Lutetia, as taken by Rosetta during the July flyby. Image Credit: mage credit: ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

In understanding more about asteroids and comets, astronomers are better able to hone their model of how our Solar System formed. By studying the composition and frequency of impacts of various asteroids, they can improve their data of just how things have changed since the primordial Solar System.

You can bet your boulders that Rosetta isn’t the only spacecraft to be making multiple rendezvous missions with the smaller denizens of our Solar System. Close flybys, impacts and landings on asteroids and comets are becoming almost commonplace for spacecraft.

There’s the Deep Impact mission, which slammed a huge copper weight into the comet Tempel 1, and has since been renamed EPOXI and is set to approach the comet Hartley 2. The upcoming approach of Vesta and Ceres by the Dawn mission is very much anticipated, and of course the recent success of the Hayabusa asteroid explorer has been a terrific tale of just how much we stand to learn from the trail of small celestial cairns that lead into our past.

Source: ESA, DPS Press Release

No Glory: NASA Delays Climate Change Satellite Mission

Artists impression of the Glory satellite at work. Credit: NASA

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A satellite mission to study climate change on Earth has been delayed due to problems with its solar arrays. The Glory mission was scheduled for a November 22, 2010 launch, but it now has been tentatively pushed back to February 23, 2011. Reportedly, ground testing revealed a problem with a mechanism in one of the two solar panels on the Glory satellite. “The new launch date provides the necessary additional time required to complete preparations for the rocket and the spacecraft,” said a NASA status report issued on Friday. The mission is slated to launch on an Orbital Sciences Taurus XL rocket from Vandenberg Air Force Base in California.

The $424 million Glory mission will gather data to help scientists to better understand the Earth’s energy budget. It will look at the properties of aerosols, including black carbon, in the Earth’s atmosphere and climate system, and enable a greater understanding of the seasonal variability of aerosol properties.

It will also collect data on solar irradiance for the long-term effects on the Earth climate record, helping to help in our understanding whether the temperature increase and climate changes are by-products of natural events or whether the changes are caused by man-made sources is of primary importance.

On the last Taurus XL launch in February 2009 — for the Orbiting Carbon Observatory, another NASA climate change research satellite — a fairing failed to separate, and the mission failed.

Source: KSC

Astronomy Cast Ep. 200: The Mariner Program

Mariner 10

Congratulations to Fraser Cain and Dr. Pamela Gay on Astronomy Cast podcast #200! This week’s podcast is about the Mariner program, the first interplanetary series of missions. These successful spacecraft visited Mercury, Venus, and Mars, and laid the groundwork for the US missions to the outer planets. Let’s take a look at the program and their incredible accomplishments.

Click here to download the episode

The Mariner Program – Show notes and transcript

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