NASA 'effectively ruling out' asteroid collision with Mars

[HURAKAN]

Ominous Asteroid Threatens Mars
Alicia Chang, Associated Press e-mail share bookmark print

A newly discovered hunk of space rock has a one in 75 chance of slamming into the Red Planet on Jan. 30, scientists said Thursday.

"These odds are extremely unusual. We frequently work with really long odds when we track ... threatening asteroids," said Steve Chesley, an astronomer with the Near Earth Object Program at NASA's Jet Propulsion Laboratory.

The asteroid, known as 2007 WD5, was discovered in late November and is similar in size to an object that hit remote central Siberia in 1908, unleashing energy equivalent to a 15-megaton nuclear bomb and wiping out 60 million trees.

Scientists tracking the asteroid, currently halfway between Earth and Mars, initially put the odds of impact at 1 in 350 but increased the chances this week. Scientists expect the odds to diminish again early next month after getting new observations of the asteroid's orbit, Chesley said.

"We know that it's going to fly by Mars and most likely going to miss, but there's a possibility of an impact," he said.

If the asteroid does smash into Mars, it will probably hit near the equator close to where the rover Opportunity has been exploring the Martian plains since 2004. The robot is not in danger because it lies outside the impact zone. Speeding at 8 miles a second, a collision would carve a hole the size of the famed Meteor Crater in Arizona.

In 1994, fragments of the comet Shoemaker-Levy 9 smacked into Jupiter, creating a series of overlapping fireballs in space. Astronomers have yet to witness an asteroid impact with another planet.

"Unlike an Earth impact, we're not afraid, but we're excited," Chesley said.
_______________________________________________________________________________________________________

More information on 2007 WD5. I'll be keeping an eye on this as it develops over the next month.

[HURAKAN]

The current position of asteroid 2007 WD5, with its orbit shown in blue. The asteroid's orbit stretches from just outside the Earth's orbit at its closest point to the Sun, to the outer reaches of the asteroid belt at its farthest.



Uncertainty Region for 2007 WD5 at encounter with Mars, shown as white dots. The thin white line is the orbit of Mars. The blue line traces the motion of the center of the uncertainty region, which is the most likely position of the asteroid.



Animation showing the motion of the uncertainty region of 2007 WD5 as it approaches Mars.The thin white line is the orbit of Mars. The blue line traces the motion of the center of the uncertainty region, which is the most likely position of the asteroid.

Recently Discovered Asteroid Could Hit Mars in January

Steve Chesley and Paul Chodas
NASA/JPL Near-Earth Object Program Office
December 21, 2007

A recently discovered asteroid which passed close to the Earth in November, is now headed towards a very close passage by Mars in late January, and there is a small chance that it could hit that planet. The probability of a collision is only 1 chance in 75, but scientists are excited about the possibility. If it happens, the impact would occur on January 30, 2008 at around 10:55 UT (2:55 a.m. PST).

In the likely event that the asteroid misses Mars, it could come back to the vicinity of the Earth years or decades later, but our routine hazard monitoring shows that there is no threat of an impact with the Earth.

Designated 2007 WD5, the asteroid was discovered on Nov. 20, 2007 by the NASA-funded Catalina Sky Survey using a 1.5m telescope on Mt. Lemmon, near Tucson. The object had already passed within 7.5 million km (5 million miles) of the Earth on Nov. 1, before it was discovered. Based on its magnitude, we estimate the asteroid to be about 50 meters (160 feet) across. As the accompanying diagram shows, it has already reached the halfway point between Earth and Mars. When it closes in on Mars, it will approach from the day side, and would then be very difficult to observe from any of the spacecraft on or around Mars. Our current best estimate predicts the asteroid will miss Mars by 50,000 km, but the miss distance is highly uncertain because the asteroid's path is not known with sufficient accuracy. The uncertainty region during the Mars encounter currently extends over a million kilometers (700,000 miles) along a very slender ellipsoid only 1200 km (700 miles) wide, but the ellipsoid does intersect Mars. The zone of potential impact on the surface of Mars is approximately 800 km wide, and sweeps across the Martian equator from southwest to northeast, crossing the equator at roughly 30 deg W longitude. The MER Opportunity rover is close to the southern edge of this possible impact zone but clearly outside it.

The asteroid is becoming increasingly difficult to observe, since it is receding from the Earth and the waxing Moon is approaching the same part of the sky. But it should become observable again early in January. These new measurements will lead to a significant improvement in the orbit accuracy, and we will then be able to refine the probability that the asteroid might collide with Mars.

If the asteroid is indeed on a collision course, it would hit Mars with a velocity of about 13.5 km/s (8.4 miles per second), and would produce an explosion equivalent to about 3 MT of TNT. We can only speculate as to the effects of such an impact, but it would be reasonable to expect a crater nearly a kilometer across and a significant amount of dust lifted into the atmosphere.

An impact would not be unprecedented: 21 fragments of Comet Shoemaker-Levy 9 impacted Jupiter in July, 1994. Those impacts were predicted with near certainty almost a year before the impact. But, with a 1-in-75 chance, this asteroid's possible impact with Mars is far from certain.

[JonathanBelles]

wow!!! will we be able to see Mars near (possible) collision time?

[HURAKAN]

Mars won't be visible at the time of the possible impact. http://www.weatherunderground.com/sky/S ... n=0&Hour=7

[Ptarmigan]

This will be interesting to watch. I remember Shoemaker-Levy 9 impact on Jupiter in 1994.

[Aslkahuna]

Mars is just past opposition in January and will be visible in the sky from the Western US westward to the sunset terminator (and thus Hawaii) at the predicted time of impact. Thus, the large telescopes in NM,AZ,CA, SW TX, and HI should be able to observe any impact that occurs if skies are clear. Whether or not small amateur scopes will be able to see the impact is debateable though the dust cloud after impact might be visible in smaller scopes. Here in SV and neighboring areas we have a few amateur scopes of 1 meter diameter so they may also be able to see any impact that occurs.

Steve

[HURAKAN]

Asteroid 'may hit Mars in January'
Email Print Normal font Large font December 23, 2007 - 9:58AM

Mars could be in for an asteroid hit.

A newly discovered hunk of space rock has a one in 75 chance of slamming into the Red Planet on January 30, US scientists said.

"These odds are extremely unusual. We frequently work with really long odds when we track ... threatening asteroids," said Steve Chesley, an astronomer with the Near Earth Object Program at NASA's Jet Propulsion Laboratory.

The asteroid, known as 2007 WD5, was discovered in late November and is similar in size to the Tunguska object that hit remote central Siberia in 1908, unleashing energy equivalent to a 15-megaton nuclear bomb that wiped out 60 million trees.

Scientists tracking the asteroid, which is halfway to Mars, initially put the odds of impact at one in 350 and increased the chances this week after analysing the data. Scientists expect the odds to diminish again early next month after getting new observations of the asteroid's orbit, Chesley said.

"We know that it's going to fly by Mars and most likely going to miss, but there's a possibility of an impact," he said.

If the asteroid does smash into Mars, it will likely aim near the equator close to where the rover Opportunity has been exploring the Martian plains since 2004. The robot is not in danger because it lies outside the impact zone. Speeding at 12.8km a second, a collision would carve a hole the size of the famed Meteor Crater in Arizona.

In 2004, fragments of the comet Shoemaker-Levy 9 smacked into Jupiter, creating a series of overlapping fireballs in space. Astronomers have yet to witness an asteroid impact with another planet.

"Unlike an Earth impact, we're not afraid, but we're excited," Chesley said.

© 2007 AP
___________________________________________________________________________________________

Just another oops!!

[HURAKAN]

Chance of Asteroid Hit on Mars Increases
By ALICIA CHANG – 5 hours ago

LOS ANGELES (AP) — The chance of a football field-sized asteroid plowing into Mars next month has been increased to 4 percent, scientists said Friday after analyzing archival data.

Though still a long shot, some researchers are hoping for a cosmic smash.

"I think it'll be cool," said Don Yeomans, who heads the Near-Earth Object Program at NASA's Jet Propulsion Laboratory. "Usually when an asteroid is headed toward Earth, I'm not rooting for an impact."

The space rock, known as the nondescript 2007 WD5, was discovered in late November by the NASA-funded Catalina Sky Survey in Arizona. Based on the latest information available, scientists said last week there was a 1-in-75 chance the asteroid could hit Mars on Jan. 30.

The odds were increased to 1-in-25 this week after a Ph.D. student pored through the archives and plotted the asteroid's motions before its official discovery. The new information allowed scientists to improve their calculations of the asteroid's orbit and flight path.

Scientists will continue to monitor the asteroid to better predict the possibility of a Martian impact. Yeomans said he expects the odds to decrease with new observations gathered early next year.

The likelihood of an asteroid hit usually "peaks before plummeting to zero with additional data," he said.

The asteroid poses no threat to Earth and is closing in on the Red Planet at 27,900 mph.

Should a collision occur, it would likely blast a half-mile-wide crater north of where the rover Opportunity has been exploring since 2004.

The impact could release energy similar to the 1908 Tunguska object that exploded over remote central Siberia and wiped out 60 million trees.

On the Net:
Near Earth Object Program: http://neo.jpl.nasa.gov/

[RL3AO]

Sweet! This would be great for collecting data.

[Coredesat]

Hopefully they'll be able to get the rover into a good position by the time of the impact.

[JonathanBelles]

Hopefully they'll be able to get the rover into a good position by the time of the impact.

And the Orbiter.

This will be interesting to watch.

[tropicana]

i was listening to some guy on the radio last night (late), he was saying the moon gets impacted all the time (hence all the craters). The asteroid impact on Mars he went on to say would be significant if you were happening to stand near or at the point of impact, but say you were just a few miles away, it wouldn't really affect you, so it will be local impact on Mars. Finally, he said there is no risk to planet Earth, since the fragments won't be able to rain down on us.
If a Mars fragment landed in my neighborhood, you better believe I'd keep it! haha

-justin-

[Aslkahuna]

Mars fragments HAVE landed on Earth and you can even buy a piece provided you are willing to pay thousands of dollars per gram. We also have Lunar fragments that have landed. I have a couple of meteorite pieces myself-the prized on is a piece of the Pueblito de Allende which has dust grains (of Interstellar Origin) that predate the Solar System.

Steve

[Beam]

Better Mars than us!

[tropicana]

Better Mars than us!

hahaha yeah u can say that again!

[HURAKAN]

Martian Asteroid Collision Chances Now One In 28
January 4, 2008 7:58 a.m. EST

Isabelle Duerme - AHN News Writer
Washington, D.C. (AHN) - An asteroid spotted while on a path towards Mars is now given a one in 28 chance of colliding with the Red Planet. Scientists have predicted that the body will be flying by Mars on January 30, 2008, but have also considered the possibility of the object hitting the planet.

The chance of collision was a significant change from a couple of weeks ago, when scientists deemed probabilities were 1 in 75, while taking readings from the Magdalena Ridge Observatory in New Mexico. It was, however a drop the one in 25 estimate based on readings taken on December 28, 2007.

Scientists will continue to monitor the path of the asteroid, noting that any chances that drop below 100 are something to be given attention.

The chances might eventually drop to zero should the asteroid even narrowly miss Mars by a few miles, said TG Daily, citing experts.

The asteroid, named Asteroid 2007 WD5, was first spotted in late November, and was placed on the "watch list", because its apparent orbit was to pass within the Earth's vicinity.

Scientists are sitting up and taking interest in the asteroid's possible collision with Mars, as explained by Steve Chesley, scientist.

"We estimate such impacts to occur on Mars every thousand years or so," the UPI quoted Chesley.

He predicted that a collision would see the asteroid travelling 30,000 miles per hour, and leaving a half-mile wide dent on the Red Planet's surface.

Experts are comparing the possible scene of a collision to that of an asteroid near-hit back in 1908, in Siberia. The asteroid disintegrated in Earth's atmosphere. It resulted in an air explosion that leveled large forest areas.

[Coredesat]

So it's very slightly more unlikely that the asteroid will hit. This will get very, very interesting as the 30th nears.

[Ptarmigan]

This will be interesting to watch. I will deploy my telescope when it happens.

[TexasStooge]

This will be very interesting to see if the predictions are correct.

[HURAKAN]

NASA 'effectively ruling out' asteroid collision with Mars

Washington - Scientists have drastically reduced the chances of a 50-metre-wide asteroid striking Mars later this month, saying Thursday the rock will likely keep a distance of about 26,000 kilometres. US space agency NASA said it was "effectively ruling out" a collision, reducing the probability to 1 in 10,000. Ten days ago the odds stood at 1 in 25 - nearly 4 per cent.

The 2007 WD5 asteroid, discovered late November, resembles in its dimensions one that exploded over Siberia in 1908, destroying 80 million trees over an area of nearly 2,200 square kilometres. It is expected to pass Mars on January 30.

Scientists said it was natural for the probability of an impact to increase dramatically before all uncertainty is eliminated, but 1 in 25 was still an unusually large chance. Steve Chesley, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, said astronomers rarely had to deal with odds greater than 1 in a million.