Posted on by Nancy Atkinson

Crowdsourcing the Hunt for Potentially Dangerous Asteroids

Faulkes Telescope, Hawaii. Credit: ESA

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What’s the best way to look for potentially hazardous asteroids? Get as many eyes on the sky as you can. That’s the impetus behind a new partnership between the European Space Agency and the Faulkes Telescope Project, which will encourage amateur astronomers to look for asteroids, as well as providing educational opportunities that will allow students to discover potentially dangerous space rocks, too.

ESA’s Space Situational Awareness (SSA) program is part of an international effort to be on the lookout for space hazards – not only asteroids but disruptive space weather and space debris objects in Earth orbit.

But asteroids pose a problem. Often, they are hard to see because they can be very dark, they can approach rather too close before anyone sees them, and they’re often spotted only once and then disappear before the discovery can be confirmed.

That’s where crowdsourcing comes in, to get more eyes on the skies. ESA is turning to schools and amateur astronomers to help as part of Europe’s contribution to the global asteroid hunt.

This month, the UK’s Faulkes Telescope Project will become the latest team to formally support the SSA program. Spain’s La Sagra Sky Survey, operated by the Observatorio Astronomico de Mallorca, began helping SSA earlier this year.

“The wider astronomy community offers a wealth of expertise and enthusiasm, and they have the time and patience to verify new sightings; this helps tremendously,” says Detlef Koschny, Head of NEO activity at ESA’s SSA program office. “In return, we share observing time at ESA’s own Optical Ground Station in Tenerife and provide advice, support and professional validation. We’ll assist them in any way we can.”

The Faulkes Telescope Project runs both educational and research programs, based at the University of Glamorgan in the UK. The project has been active in public education and science outreach, and is a partner of the US-based Las Cumbres Observatory Global Telescope network, which owns and operates two telescopes. Faulkes supports hundreds of schools across Europe, offering free access to their online observing program to schools.

The Faulkes project has two telescopes where you can sign up for observing online: Haleakala, Hawaii (Latitude: N 20 42′ 27.35″ Longitude: W 156 15′ 21.72″) and Siding Spring, Australia (Latitude: S 31 16′ 23.5″ Longitude: E 149 04′ 13.0″)

“Our new cooperation with ESA is a great opportunity. Use of the 2 m-diameter telescopes in Hawaii and Siding Spring, Australia, will greatly enhance asteroid-spotting for the SSA programme, enabling fainter object detection and tracking from a global telescope network,” says Nick Howes, Pro-Am Program Manager at the Faulkes Telescope. “For European students, collaborating on exciting ESA activities and possibly detecting new NEOs is very appealing, as its engagement with one of the world’s great space agencies doing critical scientific work.”

While the Faulkes project focuses on schools, amateurs will be able to freely access the data archives. ESA’s archives are also open to all, and they work with amateur astronomers with the Teide Observatory Tenerife Asteroid Survey (TOTAS) team, who use a 1-meter telescope at the ESA’s Optical Ground Station on Tenerife in the Canary Islands. Since starting their SSA-sponsored survey work in January 2010, the TOTAS amateur astronomers have identified hundreds of asteroid candidates, over 20 of which have been confirmed and named.

Find out more about how where students in schools across the UK/EIRE and some European locations can sign up.

ESA’s Space Situational Awareness program

Source: ESA

Posted on by Nancy Atkinson

You Just Got a Haircut from Asteroid 2012 JU

Orbit diagram for asteroid 2012 JU. Click for interactive orbital diagram from JPL.

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OK, we admit that’s a bit of an exaggeration, but an asteroid about the size of a school bus did come fairly close to Earth yesterday! On May 13, Asteroid 2012 JU passed harmlessly between Earth and Moon. This space rock is somewhere between 8 and 17 meters across, and it came within about 190,000 kilometers (118,000 miles) from Earth — about a half a Lunar Distance (LD), or 0.0014 AU. Its looping orbit is currently closely aligned with Earth’s (click image to see JPL’s orbit diagram applet) and will be moving rather slowly away from us over the next few weeks. There are two other known space rocks that will be making somewhat close passes by Earth later this month: 2010 KK37, which might be about 43 meters wide, will come within 2.3 LD (880,000 km) on May 19, and 2001 CQ36, which might be as big as 170 meters wide, will go by at 10 LD (3.8 million km) on May 30. There is no threat of any of these asteroids hitting our planet.

Asteroids passing between the Earth and Moon happens on a fairly regular basis. Last month, on April 1, a 46-meter wide asteroid named 2012 EG5 came within 230,000 km, and on March 26 of this year, two smaller asteroids shaved by at a mere 58,000 km and 154,000 km. And in January 2012 BX34 passed by at just 59,600 km from the Earth’s surface.

Last November, a biggie, asteroid 2005 YU55, a 400 meter wide space rock came within 325,000 km of Earth.

As for the upcoming NEO’s passing by Earth, the Lunar Meteorite Hunters website suggests being ready to view the night sky with eyes and cameras to witness any other debris that may be accompanying the space rocks. If you have a meteor/fireball/bolide sighting report please let them know by filing a sighting report at their website.

Posted on by Fraser Cain

Weekly Space Hangout – May 3, 2012

Here’s the May 3, 2012 edition of the Weekly Space Hangout, where we were joined by our usual cast of space journalists, including Alan Boyle, Nicole Gugliucci, Ian O’Neill, Jason Major, Emily Lakdawalla and Fraser Cain. We were then joined by two new people, Amy Shira Teitel from Vintage Space and Sawyer Rosenstein from the Talking Space Podcast.

It was an action-packed episode talking about asteroid mining, SpaceX delays, Shuttle retirement, killer black holes, supermassive planets (aka brown dwarfs), Enceladus/Dione flybys, and a new mission to Jupiter.

Want to watch an episode live? We record the Weekly Space Hangout every Thursday at 10:00am PDT, 1:00pm EDT. The live show will appear in Fraser’s Google+ stream, or on our YouTube Channel. You can also watch it live over on Cosmoquest.org.

Posted on by Nancy Atkinson

Planetary Resources: The Video

Planetary Resources, Inc. has announced its plan to mine Near Earth Asteroids for their raw resources, ranging from water to precious metals like platinum. Using their Arkyd line of spacecraft, they will head to NEOs for exploration and extraction. One of the founders, Eric Anderson said they will launch their first spacecraft within 24 months, and eventually build ‘gas stations’ in space to enable deep space exploration.

The founders of this company say that resource extraction from asteroids will deliver multiple benefits to humanity and could be valued at billions of dollars annually. “The effort will tap into the high concentration of precious metals found on asteroids and provide a sustainable supply to the ever-growing population on Earth,” they said.

Posted on by Nancy Atkinson

Planetary Resources Group Wants to Mine Asteroids

Asteroid mining concept. Credit: NASA/Denise Watt

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Last week a new company backed by a number of high-tech billionaires said they would be announcing a new space venture, and there was plenty of speculation of what the company –– called Planetary Resources — would be doing. Many ventured the company would be an asteroid mining outfit, and now, the company has revealed its purpose really is to focus on extracting precious resources such as metals and rare minerals from asteroids. “This innovative start-up will create a new industry and a new definition of ‘natural resources,’” the group said.

Is this pie in the sky or a solid investment plan?

It turns out this company has been in existence for about three years, working quietly in the background, assembling their plan.

The group includes X PRIZE CEO Peter Diamandis, Space Adventures founder Eric Anderson, Google executives K. Ram Shriram, Larry Page and Eric Schmidt, filmmaker James Cameron, former Microsoft chief software architect Charles Simonyi — a two-time visitor to the International Space Station — and Ross Perot Jr.
Even though their official press conference isn’t until later today, many of the founders started talking late yesterday. The group will initially focus on developing Earth orbiting telescopes to scan for the best asteroids, and later, create extremely low-cost robotic spacecraft for surveying missions.

A demonstration mission in orbit around Earth is expected to be launched within two years, according to the said company co-founders, and within five to 10 years, they hope to go from selling observation platforms in orbit to prospecting services, then travel to some of the thousands of asteroids that pass relatively close to Earth and extract their raw materials and bring them back to Earth.

But this company also plans to use the water found in asteroids to create orbiting fuel depots, which could be used by NASA and others for robotic and human space missions.

“We have a long view. We’re not expecting this company to be an overnight financial home run. This is going to take time,” Anderson said in an interview with Reuters.

President and Chief Engineer Chris Lewicki talked with Phil Plait yesterday and said “This is an attempt to make a permanent foothold in space. We’re going to enable this piece of human exploration and the settlement of space, and develop the resources that are out there.”

Lewicki was Flight Director for the NASA’s Spirit and Opportunity Mars rover missions, and also Mission Manager for the Mars Phoenix lander surface operations. He added that the plan structure is reminiscent of that of Apollo: have a big goal in mind, but make sure the steps along the way are practical.

Another of the aims of Planetary Resources is to open deep-space exploration to private industry, much like the $10 million Ansari X Prize competition, which Diamandis created. In previous talks, Diamandis has estimated that a small asteroid is worth about “20 trillion dollars in the platinum group metal marketplace.”

“The resources of Earth pale in comparison to the wealth of the solar system,” Eric Anderson told Wired.

The company will reveal more details in their press conference today (April 24) at 10:30 AM PDT | 12:30 PM CDT | 1:30 PM EDT | 5:30 UTC. You can watch at this link.

Planetary Resources website

Sources: Bad Astronomy, Wired, Reuters

Posted on by Nancy Atkinson

Asteroid Lutetia Flyby Animation

All asteroids and comets visited by spacecraft as of November 2010 Credits: Montage by Emily Lakdawalla. Ida, Dactyl, Braille, Annefrank, Gaspra, Borrelly: NASA / JPL / Ted Stryk. Steins: ESA / OSIRIS team. Eros: NASA / JHUAPL. Itokawa: ISAS / JAXA / Emily Lakdawalla. Mathilde: NASA / JHUAPL / Ted Stryk. Lutetia: ESA / OSIRIS team / Emily Lakdawalla. Halley: Russian Academy of Sciences / Ted Stryk. Tempel 1, Hartley 2: NASA / JPL / UMD. Wild 2: NASA / JPL.

In today’s Weekly Space Hangout, Emily Lakdawalla from the Planetary Society mentioned an animation of recently released images from the Rosetta mission’s flyby of asteroid Lutetia. It was put together and processed by Ian Regan, and Emily suggested you play this on a hand-held device (like a smart phone) in a dark room and move it around like you yourself are maneuvering the flyby! Try it — it is a very cool effect!

And while you’re at it, you also need to check out Emily’s montage poster of asteroids and comets, below:


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Check out more pretty images of Lutetia by Emily at the Planetary Blog.

Posted on by Ken Kremer

Orion Crew Capsule Targeted for 2014 Leap to High Orbit

The Orion Exploration Flight Test-1 (EFT-1) is scheduled to launch the first unmanned Orion crew cabin into a high altitude Earth orbit in 2014 atop a Delta 4 Heavy rocket from Cape Canaveral, Florida. Artist’s concept. Credit: NASA

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NASA is on course to make the highest leap in human spaceflight in nearly 4 decades when an unmanned Orion crew capsule blasts off from Cape Canaveral, Fla., on a high stakes, high altitude test flight in early 2014.

A new narrated animation (see below) released by NASA depicts the planned 2014 launch of the Orion spacecraft on the Exploration Flight Test-1 (EFT-1) mission to the highest altitude orbit reached by a spaceship intended for humans since the Apollo Moon landing Era.

Orion is NASA’s next generation human rated spacecraft and designed for missions to again take humans to destinations beyond low Earth orbit- to the Moon, Mars, Asteroids and Beyond to deep space.


Orion Video Caption – Orion: Exploration Flight Test-1 Animation (with narration by Jay Estes). This animation depicts the proposed test flight of the Orion spacecraft in 2014. Narration by Jay Estes, Deputy for flight test integration in the Orion program.

Lockheed Martin Space Systems is making steady progress constructing the Orion crew cabin that will launch atop a Delta 4 Heavy booster rocket on a two orbit test flight to an altitude of more than 3,600 miles and test the majority of Orion’s vital vehicle systems.

The capsule will then separate from the upper stage, re-enter Earth’s atmosphere at a speed exceeding 20,000 MPH, deploy a trio of huge parachutes and splashdown in the Pacific Ocean off the west coast of California.

Lockheed Martin is responsible for conducting the critical EFT-1 flight under contract to NASA.

Orion will reach an altitude 15 times higher than the International Space Station (ISS) circling in low orbit some 250 miles above Earth and provide highly valuable in-flight engineering data that will be crucial for continued development of the spaceship.

Orion Exploration Flight Test One Overview. Credit: NASA

“This flight test is a challenge. It will be difficult. We have a lot of confidence in our design, but we are certain that we will find out things we do not know,” said NASA’s Orion Program Manager Mark Geyer.

“Having the opportunity to do that early in our development is invaluable, because it will allow us to make adjustments now and address them much more efficiently than if we find changes are needed later. Our measure of success for this test will be in how we apply all of those lessons as we move forward.”

Lockheed Martin is nearing completion of the initial assembly of the Orion EFT-1 capsule at NASA’s historic Michoud Assembly Facility (MAF) in New Orleans, which for three decades built all of the huge External Fuel Tanks for the NASA’s Space Shuttle program.

In May, the Orion will be shipped to the Kennedy Space Center in Florida for final assembly and eventual integration atop the Delta 4 Heavy rocket booster and launch from Space Launch Complex 37 at nearby Cape Canaveral. The Delta 4 is built by United Launch Alliance.

The first integrated launch of an uncrewed Orion is scheduled for 2017 on the first flight of NASA’s new heavy lift rocket, the SLS or Space Launch System that will replace the now retired Space Shuttle orbiters

Continued progress on Orion, the SLS and all other NASA programs – manned and unmanned – is fully dependent on the funding level of NASA’s budget which has been significantly slashed by political leaders of both parties in Washington, DC in recent years.

…….

March 24 (Sat): Free Lecture by Ken Kremer at the New Jersey Astronomical Association, Voorhees State Park, NJ at 830 PM. Topic: Atlantis, the End of Americas Shuttle Program, Orion, SpaceX, CST-100 and the Future of NASA Human & Robotic Spaceflight

Posted on by Ken Kremer

Dawn gets Big Science Boost at Best Vesta Mapping Altitude

Vesta imaged by NASA’s Dawn Asteroid Orbiter. Dawn is currently at work at the Low Altitude Mapping Orbit (LAMO) acquiring new imagery and spectra of much higher resolution compared to these images acquired at higher altitudes and is also filling in gaps of surface data. The image from Dawn’s Framing Camera, at left, was taken on July 24 at a distance of 3,200 miles soon after achieving orbit around Vesta. The mosaic from Dawn’s Visible and infrared spectrometer (VIR), at right, was acquired from High-altitude mapping orbit (HAMO). Credit: NASA/ JPL-Caltech/ UCLA/ ASI/ INAF/ IAPS. Collage: Ken Kremer

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NASA’s Dawn mission is getting a whopping boost in science observing time at the closest orbit around Asteroid Vesta as the probe passes the midway point of its 1 year long survey of the colossal space rock. And the team informs Universe Today that the data so far have surpassed all expectations and they are very excited !

Dawn’s bonus study time amounts to an additional 40 days circling Vesta at the highest resolution altitude for scientific measurements. That translates to a more than 50 percent increase beyond the originally planned length of 70 days at what is dubbed the Low Altitude Mapping Orbit, or LAMO.

“We are truly thrilled to be able to spend more time observing Vesta from low altitude,” Dr. Marc Rayman told Universe Today in an exclusive interview. Rayman is Dawn’s Engineer at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“It is very exciting indeed to obtain such a close-up look at a world that even a year ago was still just a fuzzy blob.”

The big extension for a once-in-a-lifetime shot at up close science was all enabled owing to the hard work of the international science team in diligently handling any anomalies along the pathway through interplanetary space and since Dawn achieved orbit in July 2011, as well as to the innovative engineering of the spacecraft’s design and its revolutionary ion propulsion system.

“This is a reflection of how well all of our work at Vesta has gone from the beginning of the approach phase in May 2011,” Rayman told me.

Simulated view of Vesta from Dawn in LAMO, low altitude mapping orbit - March, 6 2012
Credit: Gregory J. Whiffen, JPL

Dawn’s initially projected 10 week long science campaign at LAMO began on Dec. 12, 2011 at an average distance of 210 kilometers (130 miles) from the protoplanet and was expected to conclude on Feb. 20, 2012 under the original timeline. Thereafter it would start spiraling back out to the High Altitude Mapping Orbit, known as HAMO, approximately 680 kilometers above the surface.

“With the additional 40 days it means we are now scheduled to leave LAMO on April 4. That’s when we begin ion thrusting for the transfer to HAMO2,” Rayman stated.

And the observations to date at LAMO have already vastly surpassed all hopes – using all three of the onboard science instruments provided by the US, Germany and Italy.

“Dawn’s productivity certainly is exceeding what we had expected,” exclaimed Rayman.

“We have acquired more than 7500 LAMO pictures from the Framing Camera and more than 1 million LAMO VIR (Visible and Infrared) spectra which afford scientists a much more detailed view of Vesta than had been planned with the survey orbit and the high altitude mapping orbit (HAMO). It would have been really neat just to have acquired even only a few of these close-up observations, but we have a great bounty!”

“Roughly around half of Vesta’s surface has been imaged at LAMO.”

Dawn mosaic of Visible and Infrared spectrometer (VIR) data of Vesta
This mosaic shows the location of the data acquired by VIR (visible and infrared spectrometer) during the HAMO (high-altitude mapping orbit) phase of the Dawn mission from August to October 2011. Dawn is now making the same observations at the now extended LAMO (low-altitude mapping orbit) phase of the Dawn mission from December 2011 to April 2012. VIR can image Vesta in a number of different wavelengths of light, ranging from the visible to the infrared part of the electromagnetic spectrum. This mosaic shows the images taken at a wavelength of 550 nanometers, which is in the visible part of the electromagnetic spectrum. During HAMO VIR obtained more than 4.6 million spectra of Vesta. It is clear from this image that the VIR observations are widely distributed across Vesta, which results in a global view of the spectral properties of Vesta’s surface. This image shows Vesta’s southern hemisphere (lower part of the image) and equatorial regions (upper part of the image). NASA’s Dawn spacecraft obtained these VIR images with its visible and infrared spectrometer in September and October 2011. The distance to the surface of Vesta is around 700 kilometers (435 miles) and the average image resolution is 170 meters per pixel. Credit: NASA/ JPL-Caltech/ UCLA/ ASI/ INAF/ IAPS

The bonus time at LAMO will now be effectively used to help fill in the gaps in surface coverage utilizing all 3 science instruments. Therefore perhaps an additional 20% to 25% extra territory will be imaged at the highest possible resolution. Some of this will surely amount to enlarged new coverage and some will be overlapping with prior terrain, which also has enormous research benefits.

“There is real value even in seeing the same part of the surface multiple times, because the illumination may be different. In addition, it helps for building up stereo,” said Rayman.

Researchers will deduce further critical facts about Vesta’s topography, composition, interior, gravity and geologic features with the supplemental measurements.

Successive formation of impact craters on Vesta
This Dawn FC (framing camera) image shows two overlapping impact craters and was taken on Dec. 18,2011 during the LAMO (low-altitude mapping orbit) phase of the mission. The large crater is roughly 20 kilometers (12 miles) in diameter and the smaller crater is roughly 6 kilometers (4 miles) in diameter. The rims of the craters are both reasonably fresh but the larger crater must be older because the smaller crater cuts across the larger crater’s rim. As the smaller crater formed it destroyed a part of the rim of the pre-existing, larger crater. The larger crater’s interior is more densely cratered than the smaller crater, which also suggests that is it older. In the bottom of the image there is some material slumping from rim of the larger crater towards its center. This image with its framing camera on Dec. 18, 2011. This image was taken through the camera’s clear filter. The distance to the surface of Vesta is 260 kilometers (162 miles) and the image has a resolution of about 22 meters (82 feet) per pixel. Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA

The foremost science goals at LAMO are collection of gamma ray and neutron measurements with the GRaND instrument – which focuses on determining the elemental abundances of Vesta – and collection of information about the structure of the gravitational field. Since GRaND can only operate effectively at low orbit, the extended duration at LAMO takes on further significance.

“Our focus is on acquiring the highest priority science. The pointing of the spacecraft is determined by our primary scientific objectives of collecting GRaND and gravity measurements.”

As Dawn continues orbiting every 4.3 hours around Vesta during LAMO, GRaND is recording measurements of the subatomic particles that emanate from the surface as a result of the continuous bombardment of cosmic rays and reveals the signatures of the elements down to a depth of about 1 meter.

“You can think of GRaND as taking a picture of Vesta but in extremely faint light. That is, the nuclear emissions it detects are extremely weak. So our long time in LAMO is devoted to making a very, very long exposure, albeit in gamma rays and neutrons and not in visible light,” explained Rayman.

Now with the prolonged mission at LAMO the team can gather even more data, amounting to thousands and thousands more pictures, hundreds of thousands of more VIR spectra and ultra long exposures by GRaND.

“HAMO investigations have already produced global coverage of Vesta’s gravity field,” said Sami Asmar, a Dawn co-investigator from JPL. Extended investigations at LAMO will likewise vastly improve the results from the gravity experiment.

Dawn Spacecraft Current Location and Trajectory - March, 6 2012. Credit: Gregory J. Whiffen, JPL

“We always carried 40 days of “margin,” said Rayman, “but no one who was knowledgeable about the myriad challenges of exploring this uncharted world expected we would be able to accomplish all the complicated activities before LAMO without needing to consume some of that margin. So although we recognized that we might get to spend some additional time in LAMO, we certainly did not anticipate it would be so much.”

“As it turned out, although we did have surprises the operations team managed to recover from all of them without using any of those 40 days.”

“This is a wonderful bonus for science,” Rayman concluded.

“We remain on schedule to depart Vesta in July 2012, as planned for the past several years.”

Dawn’s next target is Ceres, the largest asteroid in the main Asteroid Belt between Mars and Jupiter

Posted on by Nancy Atkinson

Will Asteroid 2011 AG5 Hit Earth in 2040?

The orbit of asteroid 2011 AG5 carries it beyond the orbit of Mars and as close to the sun as halfway between Earth and Venus. Image credit: NASA/JPL/Caltech/NEOPO

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You may have heard about an asteroid in the news this week that has a 1 in 625 chance of hitting Earth on Feb. 5, 2040. So, will this asteroid, named 2011 AG5, really hit our planet? The quick answer is, probably not. But astronomers will need more observations of this asteroid to say one way or the other for sure.

“Because of the extreme rarity of an impact by a near-Earth asteroid of this size, I fully expect we will be able to significantly reduce or rule out entirely any impact probability for the foreseeable future,” said Donald Yeomans, head of the Near-Earth Object Observations Program at NASA’s Jet Propulsion Laboratory.

Yeomans classified the chance of impact as “unlikely” and here are some facts that we do know about Asteroid about 2011 AG5:

What is the potential that this asteroid will impact Earth?

Currently astronomers have this asteroid ranked as a “1” on the 1 to 10 Torino Impact Hazard Scale. A “1” means this asteroid will have a pass near the Earth that poses no unusual level of danger. Current calculations show the chance of collision is extremely unlikely with no cause for public attention or public concern. Very likely, subsequent telescopic observations will lead to re-assignment to Level 0. The 1 in 625 chance is what the predictions are for the data that NASA has right now. Further observations will likely decrease the odds, and may even bring it to zero.

How big is this asteroid?

2011 AG5 is a 140-meter-wide (460 feet) space rock. Its composition is not yet known – whether it is a rocky, iron or icy asteroid.

How many Near Earth asteroids are out there?

Asteroid 2011 AG5 is one of 8,744 near-Earth objects that have been discovered so far, as of this week (March 1, 2012). NEOs are objects that come within 1.3 AU of the Sun (with Earth at 1 AU, so it means they pass through our neighborhood.)

1,305 of these NEOs have been classified as Potentially Hazardous Asteroids (PHAs), which are those that are larger than about 150 m (500 ft) and come within 0.05 AU of Earth’s orbit, so 2011 AG5 is right at the edge of that classification.

How was this asteroid discovered?

It was discovered on Jan. 8, 2011, by astronomers using a 60-inch Cassegrain reflector telescope located at the summit of Mount Lemmon in the Catalina Mountains north of Tucson, Arizona.

Where is 2011 AG5 now?

Its orbit carries it as far out as beyond Mars’ orbit and as close to the Sun as halfway between Earth and Venus. See the image above for its approximate current location. Its proximity to the Sun from our vantage point on Earth means astronomers can’t make observations right now.

When will astronomers find out more and be able to make better predictions?

“In September 2013, we have the opportunity to make additional observations of 2011 AG5 when it comes within 91 million miles (147 million kilometers) of Earth,” said Yeomans. “It will be an opportunity to observe this space rock and further refine its orbit.”

Yeomans added that even better observations will be possible in late 2015.

Will this asteroid come close to Earth before 2040?

2011 AG5 will next be near Earth in February of 2023 when it will pass the planet no closer than about 1.2 million miles (1.9 million kilometers). In 2028, the asteroid will again be in the area, coming no closer than about 12.8 million miles (20.6 million kilometers). The Near-Earth Object Program Office says the Earth’s gravitational influence on the space rock during these flybys has the potential to place the space rock on an impact course for Feb. 5, 2040, but this has very unlikely odds of occurring at 1-in-625.

“Again, it is important to note that with additional observations next year the odds will change and we expect them to change in Earth’s favor,” said Yeomans.

Screenshot from the Impact Earth website animation.

If Asteroid 2011 AG5 were to hit Earth, what is the potential for damage to Earth?

According to calculations from the Impact Earth website, an object of this size would begin to break up in Earth’s atmosphere at an altitude of 65500 meters (215,000 ft). Some of the larger pieces would reach the ground, with the pieces hitting Earth’s surface (ground) at a velocity Of 2.64 km/s (1.64 miles/s). The impact energy would be 7.52 x 10^15 Joules, or 1.8 MegaTons.

This would not cause any global problems, as the planet as a whole would not be strongly disturbed by the impact.

The broken projectile fragments would strike the ground in an ellipse about 1.17 km by 0.824 km in diameter, and the result of the impact is a crater field, not a single crater. The largest crater would be about 400 meters in diameter (1,310 feet). The impact would create a Richter Scale Magnitude-like event of 4.8.

If you were 1-10 km away from the impact area, you would feel a sensation like a heavy truck striking building. Standing cars would be rocked noticeably. Indoors, dishes and windows, might be disturbed and walls might make a cracking sound. An air blast at speeds of 26.3 m/s = 58.9 mph would arrive approximately 10 – 30 seconds after impact.

If this impactor hit in an ocean, the impact-generated tsunami wave would arrive approximately 6.18 minutes after impact if you were 10 km away, with a wave amplitude is between: 4.78 and 9.55 meters (15.7 feet and 31.3 feet).

How often do asteroids hit the Earth?

Yeomans said that every day, Earth is pummeled by more than 100 tons of material that spewed off asteroids and comets. Fortunately the vast majority of this “spillover” is just dust and very small particles. “We sometimes see these sand-sized particles brighten the sky, creating meteors, or shooting stars, as they burn up upon entry into Earth’s atmosphere,” Yeomans said in his “Top Ten Asteroid Factoids” article. “Roughly once a day, a basketball-sized object strikes Earth’s atmosphere and burns up. A few times each year, a fragment the size of a small car hits Earth’s atmosphere. These larger fragments cause impressive fireballs as they burn through the atmosphere. Very rarely, sizable fragments survive their fiery passage through Earth’s atmosphere and hit the surface, becoming meteorites.”

More info:
Catalina Sky Survey
Minor Planet Center
Asteroid and Comet Impact Hazards website from NASA
NASA’s Near Earth Object Program
Impact Earth website

Posted on by Amy Shira Teitel

NEOShield: a Preemptive Strike Against Asteroids

What an asteroid hitting the Earth might look like. Image credit: NASA/Don Davis.

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Scientists aren’t entirely sure when the last major asteroid hit the Earth, but it’s certain to happen again. Alan Harris, asteroid researcher at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR), is hoping to head the next one off. Last month, Harris established an international collaboration of 13 researchers to investigate methods of shielding the Earth from near Earth objects (NEOs). The project is, appropriately, called NEOShield.

Asteroids approaching the planet typically travel between 5 and 30 kilometres (about 5 to 19 miles) per second. As that speed, a moderate sized body can have major consequences. The Barringer Crater in Arizona, often referred to as Meteor Crater, is a 1,200 metre crater (about 3,950 feet or 0.7 miles) that scientists hypothesize was caused by a 50 metre (164 feet) meteor.

The bad news is that there are thousands of known NEOs just like the one that made Meteor Crater, leading experts to posit that a dangerous collision could occur as often as every two hundred years.

Meteor Crater near Winslow, Arizona. Image credit: NASA.

The good news is that it’s possible to stop an asteroid hitting the Earth. You just have to be in the right place at the right time to give the object the right push in another direction.

Scientists are focusing on possible methods of redirecting threatening asteroids so they miss the Earth. “In order to modify their orbit and prevent a collision with Earth, a force must be exerted on them,” explains Alan Harris. “And at the precise time, as well.” One way to do this is to have a spacecraft impact a threatening asteroid, imparting enough force to change its orbit. “In my opinion, this is a very practical method,” said Harris. But there are still questions to answer, like how to guide the spacecraft to a moving target at the right angle for the right impact and how to minimize the effects of fuel movement on the spacecraft’s path.

Another way is to use the spacecraft’s gravitational pull to nudge the asteroid into a different orbit. If the object is far enough away, a tiny tug could have a big effect. But so far, “this method only exists on paper,” said Harris, “but it could work.”

An asteroid, docile in space but deadly to Earth. Image credit: NASA/JPL

Another third, less appealing prospect, is to use explosive power to break up an Earth-bound asteroid. But this could be disastrous, creating a shower of debris instead of one solid piece. As such, Harris considers this method a last resort. “If a very large, dangerous object with a diameter of one kilometre [0.6 miles] or more is discovered,” explains Harris, changing its orbit won’t be a option. “The greatest force we would be able to use to divert the asteroid from its path would be a nuclear explosion. This technique is regarded as a very controversial.”

Over the next three years, during which the European Union will support the project with four million Euros and international partners will contribute an additional 1.8 million Euros, the NEOShield project will research these defence methods. The scientists will focus on data from asteroid observations and lab experiments to generate computer simulations, ultimately determining how best to protect the Earth from future devastating impacts.

Source: DLR News Portal