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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No visible material from asteroid Itokawa was found inside the second compartment of a canister returned to Earth by the Hayabusa spacecraft. However, JAXA also announced that more micron-sized grains have been found in the first compartment, opened earlier this year. Reportedly, the first compartment has about 1,500 tiny particles, however some might be aluminum particles from the container itself. But about 20 grains were rocky or mineral-based. However, according to the Daily Yomiuri Online, no visible material was inside the second chamber, although further investigations of the second compartment will be done with a special microscope.
Hayabusa attempted to land on Itokawa twice. The cylindrical canister was divided into two chambers, and the second chamber was to contain material collected during the spacecraft’s first landing.
JAXA officials expect the second compartment to contain more microscopic particles from Itokawa since the first landing was longer than the second.
As far as the particles from the first chamber, several have been observed with an electron microscope, and according to UmannedSpaceflight.com, the “rocky” ones are 30 microns in size, with several larger ones are about 100 microns.
JAXA hopes to provide more insight on the nature of the grains by the end of the year.
(596) Scheila, the asteroid with a tail. Image credit: Peter Lake
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When is an asteroid not an asteroid? When it turns out to be a comet, of course. Has this ever happened before? Why, yes it has. In fact it was just announced December 12, 2010 that the asteroid (596) Scheila has sprouted a tail and coma! This is likely a comet that has been masquerading as an asteroid.
Taken from New Mexico Skies between 8h15m and 11h45m UT. The image is a stack of 10 x 600 sec exposures using a 20 inch RCOS and STL11K camera. Scale is 0.91 asec/px.. Image courtesy of Joseph Brimacombe
Steve Larson of the Lunar and Planetary Laboratory (LPL), University of Arizona first reported that images of the minor planet (596) Scheila taken on December 11th showed the object to be in outburst, with a comet-like appearance and an increase in brightness from magnitude 14.5 to 13.4. The cometary appearance of the object was confirmed by several other observers within hours.
A quick check of archived Catalina images of Scheila from October 18, November 2 and November 11 showed Scheila to look star-like, which is what asteroids look like from Earth. They just happen to be moving across the field of view in contrast to the fixed background stars. The image taken by Catalina on December 3rd shows some slight diffuseness and an increase in overall brightness. So, it appears this event began on or around December 3rd.
Upon hearing the news, there was some speculation that this might be evidence of an impact event. Had something crashed into asteroid Scheila? It seems unlikely, and this is a story we have heard before.
The asteroid discovered in 1979 and named 1979 OW7 was lost to astronomers for years and then recovered in 1996. It was subsequently renamed 1996 N2. That same year it was discovered to have a comet-like appearance, and many believed this was the signature of an impact between two asteroids. After years of inactivity 1996 N2 sprouted a tail again in 2002. One collision between two asteroids was unlikely enough. The odds of it happening again to the same object were essentially zero. What we had was a comet masquerading as an asteroid. This object is now known by its cometary name 133P/Elst-Pizarro, named after the two astronomers who discovered its initial cometary outburst.
The 2002 outburst and the discovery of more active asteroids showing mass-loss led to a paper (Hsieh and Jewitt 2006, Science, 312, 561-563) introducing an entirely new class of solar system objects, Main Belt Comets (MBC). MBCs look like comets because they show comae and have tails but they have orbits inside Jupiter’s orbit like main belt asteroids.
The most likely cause of the mass loss activity in MBCs is sublimation of water ice as the surface of the MBC is heated by the Sun. This is suggested most strongly by the behavior of the best-studied example, namely 133P/Elst-Pizarro. Its activity is recurrent, and it is strongest near and after perihelion, the point in its orbit nearest the Sun, like other comets.
MBCs are interesting to astronomers because they appear to be a third reservoir of comets in our solar system, distinct from the Oort cloud and Kuiper belt. Since we know of no way for these other reservoirs to have deposited comets in the inner solar system, the ice in MBCs probably has a different history than the ice in the outer comets. This allows researchers to study the differences in the Sun’s proto-planetary disk at three separate locations. This might lead to information on the Earth’s oceans, one of the continuing lines of investigation by solar system scientists.
Now it seems we have another MBC to add to the sample. And Scheila will probably be getting a new name soon. Asteroid (596) Scheila was discovered Feb. 21, 1906, by A. Kopff at Heidelberg. The 113Km in diameter ‘asteroid’ was named after an acquaintance, an English student at Heidelberg. In the future it will be called XXXP/Lawson or something similar, and Kopff’s Scheila will become just another footnote in the history of astronomical nomenclature.
Astronomers have been busy trying to determine the spin period and composition of Venus’ moon. December 8, 2010, results were announced by JPL/Caltech scientists, led by Michael Hicks.
“Wait a minute; back up”, I hear you ask. “Venus has a Moon?”
Of course it does. Well, kind of…
Let me explain.
It has the rather unfortunate name of 2002 VE68. That is because it was discovered on November 11, 2002 by LONEOS, the Lowell Observatory Near Earth Object Search. 2002 VE68 is an earth orbit-crossing asteroid that has been designated a Potential Hazardous Asteroid by the Minor Planet Center. For obvious reasons, this makes it a very interesting subject of study for JPL scientists.
2002 VE68 used to be a run of the mill, potential impact threat, Near Earth Object. But approximately 7000 years ago it had a close encounter with Earth that kicked it into a new orbit. It now occupies a place in orbit around the Sun where at its closest it wanders inside the orbit of Mercury and at its furthest it reaches just outside the orbit of the Earth. It is now in a 1:1 orbital resonance with Venus.
An orbital resonance is when two orbiting bodies exert a regular, periodic gravitational influence on each other due to their orbital periods being related by a ratio of two small numbers. For example, Pluto and Neptune are in an orbital resonance of 2:3, which simply means for every two times Pluto goes around the Sun, Neptune makes three trips around.
In the case of Venus and 2002 VE68, they both take the same time to orbit the Sun once. They are in a 1:1 orbital resonance. So by definition, 2002 VE68 is considered a quasi-satellite of Venus. If you watch the Orbital Viewer applet at the JPL small body page you can watch this celestial dance as the two bodies orbit the Sun and each other as 2002 VE68 dodges Earth and Mercury in the process.
Often these resonances result in an unstable interaction, in which the bodies exchange momentum and shift orbits until the resonance no longer exists. In this case, scientists believe 2002 VE68 will only remain a Venusian quasi-satellite for another 500 years or so.
So getting back to the story, Hicks and his team used the recent close apparition of 2002 VE68 to do photometric measurements over the course of three nights in November using the JPL Table Mountain 0.6m telescope near Wrightwood, California. From the color data they obtained they determined that 2002 VE68 is an X type asteroid. This is a group of asteroids with very similar spectra that could potentially have a variety of compositions. They are further broken down into Tholen classification types as either E, M or P types. Unfortunately Hicks’ team was not able to resolve the sub-classification with their equipment.
They were able to determine the approximate size of the asteroid to be 200 meters in diameter, based on its absolute magnitude, and they determined a spin rate of 13.5 hours. The amplitude of the fluctuation on the light curve of 2002 VE68 could imply hat it is actually a contact binary, two clumps of asteroidal material orbiting a center of mass in contact with each other.
For more information on some of the strange and curious beasts in the asteroidal zoo, visit the NASA Near Earth Object Program website.
A small asteroid will make a fairly close flyby of Earth tonight, November 16, 2010 at 10:44 p.m. EST (0344 GMT), but it is not a threat to hit the planet. Plus, at 3 meters wide, (10 ft) the asteroid, named 2010 WA, would break apart if it hit Earth’s atmosphere. Still, finding and tracking the small asteroid is “good practice in detection,” wrote NASA’s @AsteroidWatch Twitter feed.
2010 WA will pass about 1/10 lunar distance, or about 38,000 kilometers (24,000 miles) away, and have a magnitude of about 14.5, so it won’t be visible “without a good sized telescope” said @AsteroidWatch. But if you do have such a telescope, the asteroid could be seen over the middle to east coast of US.
For references, geostationary satellites are in orbit about 36,000 km (22,350 miles) up, while the International Space Station is about 350 km (220 miles) above Earth.
NASA is constantly on the lookout for asteroids, or Near Earth Objects (NEO), and has a mandate by Congress for the “Spaceguard” survey to find all asteroids around 40 meters and larger by 2020.
NASA says several teams of astronomers worldwide are surveying the sky to find NEOs. One of the most most productive NEO surveys is the LINEAR search program of the MIT Lincoln Lab, carried out in New Mexico with US Air Force and NASA support. The LINEAR team, which operates two search telescopes with one-meter aperture. Recently, the Catalina Sky Survey in Tucson, Arizona has been extremely productive, as well. Other active survey groups include the NEAT search program in Hawaii, carried out jointly by the NASA Jet Propulsion Lab and the US Air Force; the Spacewatch survey at the University of Arizona, and the LONEOS survey at Lowell Observatory in Flagstaff Arizona. Other astronomers — many of them amateurs — follow up the discoveries with supporting observations.
An electron micrograph image of the edge of a special Teflon spatula that scraped the interior surfaces of Hayabusa's sample return capsule. Credit: JAXA
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The Japan Aerospace Exploration Agency (JAXA) has confirmed that the tiny particles inside the Hayabusa spacecraft’s sample return container are in fact from the asteroid Itokawa. Scientists examined the particles to determine if the probe successfully captured and brought back anything from the asteroid, and in a press release said “about 1,500 grains were identified as rocky particles, and most were determined to be of extraterrestrial origin, and definitely from Asteroid Itokawa.”
These are the first samples from an asteroid ever returned to Earth; the only other extraterrestrial samples brought back to Earth came from the Apollo missions to the Moon. See correction, below.
Previously, JAXA said that although particles were inside the container, it wasn’t clear if they were from the asteroid or if they could be of terrestrial origin (dust from Earth that could have been inside the container).
The particles samples were collected from the chamber by a specially shaped Teflon spatula and examined with a scanning electron microscope. There were two chambers inside the container, and from the press release (in Japanese) it appears all the particles were found in one chamber, Chamber A.
Most of the particles are extremely small, about 10 microns in size and require special handling and equipment. Unfortunately they aren’t the “peanut-sized” chunks of rock that the mission originally hoped to capture. This will make analyzing the particles difficult, but not impossible.
Hayabusa's sample return cannister and parachute on the ground in the Australian outback. Credit: JAXA
During the seven-year round trip journey, Hayabusa arrived at Itokawa in November, 2005. The mechanism that was intended to capture the samples apparently failed, but scientists were hopeful that at least some dust had made its way into the return canister. After a circuitous and troubled-filled return trip home, the sample return capsule was ejected and landed in Australia in June of this year.
Here are the other successful sample return missions:
Apollo Moon missions (1969-1972)
Soviet Union’s Luna 16 (1970) returned 101 grams of lunar soil
Luna 20 (1974) returned 30 grams
Luna 24 (1976) returned 170.1 grams.
The Orbital Debris Collection (ODC) experiment, deployed on the Mir space station for 18 months during 1996–1997, used aerogel to capture interplanetary dust particles in orbit.
Genesis (2001-2004) captured and returned molecules collected from the solar wind. It crashed in the Utah desert, but samples were able to be retreived.
Stardust (1999-2006) collected particles from the tail of a comet, as well as a few interstellar dust grains.
A 20-km asteroid has just been predicted to hit Earth and you want to know if a. You should run for it, b. You should call Bruce Willis, or c. You can rest easy because your part of the world won’t be affected. All you have to do is input the parameters of the asteroid on the recently updated “Impact Earth” website, and you’ll find out everything about what an impactor will do to Earth, including an estimate of the size of the crater, how far away you’ll need to be in order to avoid being affected by the impact (and if that is possible), tsunami wave height, and other details of the subsequent disaster. The fun part is, you can simulate the destruction of Earth multiple times, without hurting anyone.
The original Impact Earth website was created in 2002 for use by NASA and homeland security. The new version, built in a collaboration between Purdue University and Imperial College London, is more user-friendly for the general public, as well as providing more visual details of an impact. Besides being rather fun to play around with, the website is highly educational about what a various sized impacts would do Earth, depending on if it hit ground or water.
Computer generated simulation of an asteroid strike on the Earth. Credit: Don Davis/AFP/Getty Images
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During the past 24 hours, the Earth has been hit by about a million small meteoroids – most of which burned up in the atmosphere as shooting stars. This happens every day. And occasionally – once every 10,000 years or so — a really big asteroid (1 km in diameter or larger) comes along and smacks Earth with an extinction-level impact. That idea might cause some of us to lose some sleep. But in between are other asteroid hits that occur every 200-300 years where a medium-sized chunk of space rock intersects with Earth’s orbit, producing a Tunguska-like event, or worse.
“Those are the objects we are concerned with,” said former Apollo astronaut Rusty Schweickart, speaking at a 3-day workshop in Darmstadt, Germany which focused on plans and recommendations for global coordination and response to an asteroid threat. “We need to take action now to bring the world together and recognize this as a global threat so that we can make a cooperative international decision to act to extend the survival of life on Earth.”
There are likely about one million Near Earth Objects out there that could do substantial damage if one hit the Earth. This isn’t anything new – Earth has been in this same environment for billions years.
“What’s new is that we have now opened our eyes via telescopes and are seeing something flying by our heads, so to speak,” said Schweickart during a media event at the workshop. “When you see something flying by your head, you duck. It turns out we have the capability of ducking and causing these objects to miss us. Because we now know about this threat and because we can in fact prevent an impact, we then have a moral obligation to do so.”
Former astronaut Tom Jones, who also attended the workshop, told Universe Today that NASA hopes to find all the 500 meter objects within a few decades, “and thus through action be able to prevent an impact from that large an object, removing it from the overall asteroid hazard. Smaller objects are much more numerous (the approximately million NEOs mentioned above) and can cause city-size damage. We’ll have to search diligently for those in the coming decade and it’ll be several decades before we find those hundreds of thousands of 30-meter sized -subTunguskas.”
Schweickart discussed in a recent Universe Today article that we do possess the technology to move asteroids or change their orbits, and that this technology does need to be tested, and tested soon. But since an impact event could affect the entire world, the decisions on policies and international agreements about asteroid mitigation could actually pose a bigger challenge in dealing with an asteroid threat than putting the technology together.
“Bureaucracy is the most likely reason we will be hit with an asteroid in the future, not the technology,” said Schweickart. “That is an audacious statement to make, but if we can get past that and do our jobs right we should never be hit in the future by an asteroid that could threaten life on Earth. And it’s going to be a heck of a challenge.”
The Mission Planning and Operations Group (MPOG) workshop included astronauts and space scientists and was the latest in a series of workshop designed to offer suggestions to the UN Committee on the Peaceful Uses of Outer Space. Included were representatives from NASA, ESA, the Secure World Foundation and the Association of Space Explorers. They are working on defining future planning tasks and studies for the Group that will later be merged with findings of other experts to create a final report to the UN committee. This report will recommend how to react to an impact threat.
But there are issues such as, how changing an asteroid’s orbit could make it miss one area on Earth and instead hit another area.
“The issue of NEOs is an issue that the United nations has been considering for 10 years or so,” said Sergio Camacho, representing the UN Committee. “The reason it has to go through the UN is that when we make a decision, whatever action is taken might affect others and put them at risk where they are not at risk at the beginning. That can’t be a unilateral decision, and we need to pool the resources of space agencies in order to address the problem. It will be within the framework of the UN that we will be able to master this cooperation.”
Schweickart and the Association of Space Explorers, have been working on this issue for over 9 years and are just now beginning to see a little headway in the bureaucratic process. Everyone at the workshop agreed that political decisions and political awareness is something that has to be taken seriously.
“Two weeks ago a small object passed in between the Earth and the Moon,” said Schweickart,“ and on Halloween an object half a kilometer in diameter Is going to pass within five lunar distances of Earth — in terms of astronomical distances, that is very close. These things are happening, but I hope we areable to act soon and act responsibly without having to have a reminder” – meaning the wake-up call of an actual impact and not being prepared for it.
Near Earth Objects graphic, created by Zachary Vabolis. Used by permission.
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Just for fun, graphic design student Zachary Vabolis created this fantastic graphic showing the closest and biggest Near Earth Objects. However, Vabolis wants to make clear that the information represented here is not meant to portray that the end of the world is nigh. His image has appeared on several websites recently, and some of the headlines have included words such as “doomsday,” etc. But, that’s not what he intended.
“I’m not sure if anyone who has seen my graphic is reading more into it than I intended,” Vabolis told Universe Today, “but I wanted to state that I did not create this graphic to scare people. In fact if you look at the information it contains, Earth has almost no chance of being hit by any of the asteroids listed and NASA even mentions that as well on their website.”
Vabolis said he created the graphic because he really enjoys creating projects outside of his curriculum to help hone his skills, plus it is just a fun pastime for him. “I’ve always been fascinated by outer space so I wanted to do a graphic within that subject,” Vabolis said in an email. “I came up with the Near Earth Objects topic because it’s a fairly current subject and after doing a little research I found that no one else had created such a graphic yet.”
The graphic was created using the information on NASA’s Near Earth Object Fact Sheet website, which states, “There are no known NEO’s on a collision course with the Earth. There is a possibility that an as yet undiscovered large NEO may hit the Earth, but the probability of this happening over the next 100 years is extremely small.”
So breathe easy and enjoy learning more about NEO’s from Vabolis’ graphic. You can see more of his work at his page on Behance.
Apollo 9 astronaut Rusty Schweickart is among an international group of people championing the need for the human race to prepare for what will certainly happen one day: an asteroid threat to Earth. In an article on Universe Today published yesterday, Schweickart said the technology is available today to send a mission to an asteroid in an attempt to move it, or change its orbit so that an asteroid that threatens to hit Earth will pass by harmlessly. What would such a mission entail?
In a phone interview, Schweickart described two types of “deflection campaigns” for a threatening asteroid: a kinetic impact would roughly “push” the asteroid into a different orbit, and a gravity tractor would “tug slowly” on the asteroid to precisely “trim” the resultant change course by using nothing more than the gravitational attraction between the two bodies. Together these two methods comprise a deflection campaign.
Artist Impression of Deep Impact - Credit: NASA
“In a way, the kinetic impact was demonstrated by the Deep Impact mission back in 2005,” said Schweickart. “But that was a very big target and a small impactor that had relatively no effect on the comet. So, we haven’t really demonstrated the capability to have the guidance necessary to deflect a moderately sized asteroid.”
Most important, the gravity tractor spacecraft would arrive prior to the kinetic impactor, precisely determine the asteroid’s orbit and observe the kinetic impact to determine its effectiveness. Following the kinetic impact it would then determine whether or not any adjustment trim were required.
“You want to know what happens when you do a kinetic impact, so you want an ‘observer’ spacecraft up there as well,” Schweickart explained. “You don’t do a kinetic impact without an observation, because the impactor destroys itself in the process and without the observer you wouldn’t know what happened except by tracking the object over time, which is not the best way to find out whether you got the job done.”
So, 10-15 years ahead of an impact threat — or 50 years if you have that much time — an observer spacecraft is sent up. “This, in fact, would also be a gravity tractor,” Schweickart said. “It doesn’t have to be real big, but bigger gets the job done a little faster. The feature you are interested in the outset is not the gravity tractor but the transponder that flies in formation with the asteroid and you track the NEO, and back on Earth we can know exactly where it is.”
Schweickart said even from ground tracking, we couldn’t get as precise an orbit determination of an NEO as we could by sending a spacecraft to the object. Additionally, generally speaking, we may not know when we send an observer spacecraft what action will be required; whether an impact will be required or if we could rely on the gravity tractor. “You may launch at the latest possible time, but at that time the probability of impact may be 1 in 5 or 1 or 2,” Schweickart said. “So the first thing you are going to do with the observer spacecraft is make a precise orbit determination and now you’re going to know if it really will impact Earth and even perhaps where it will impact.”
Artist concept of an impactor heading towards an asteroid. Credit: ESA
After the precise orbit is known, the required action would be determined. “So now, if needed you launch a kinetic impactor and now you know what job has to be done,” Schweickart said. “As the impactor is getting ready to impact the asteroid, the observer spacecraft pulls back and images what is going on so you can confirm the impact was solid, –not a glancing blow — and then after impact is done, the observer spacecraft goes back in and makes another precision orbit determination so that you can confirm that you changed its velocity so that it no longer will hit the Earth.”
The second issue is, even if the NEO’s orbit has been changed so that it won’t hit Earth this time around, there’s the possibility that during its near miss it might go through what is called a “keyhole,” whereby Earth’s gravity would affect it just enough that it would make an impact during a subsequent encounter with Earth. This is a concern with the asteroid Apophis, which is projected to miss Earth in 2029, but depending on several factors, could pass through a keyhole causing it to return to hit Earth in 2036.
“So if it does go through that keyhole,” said Schweickart, “now you can use the gravity tractor capability of the spacecraft to make a small adjustment so that it goes between keyholes on that close approach. And now you have a complete verified deflection campaign.”
Schweickart said a Delta-sized rocket would be able to get a spacecraft to meet up with an asteroid. “A Delta rocket would work,” he said, “but if there is a more challenging orbit we might have to use something bigger, or we may have to use a gravity assist and do mission planning for type of thing which hasn’t been done yet. So we can get there, we can do it – but ultimately we will probably need a heavy lift vehicle.”
As for the spacecraft, we can use a design similar to vehicles that have already been sent into space.
“A gravity tractor could be like Deep Space 1 that launched in 1998,” Schweickart said. “ You can make any spacecraft into a gravity tractor fairly easily.”
Rusty Schweickart
But it hasn’t been demonstrated and Schweickart says we need to do so.
“We need to demonstrate it because we – NASA, the technical community, the international community — need to learn what you find out when you do something for the first time,” he said. “Playing a concerto in front of an audience is quite different from playing it alone in your house.”
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.”
