1-in-75 Chance Of Tunguska-Size Impact On Mars
Written by Ian O'Neill
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A 164-foot (50 meter) wide asteroid will be crossing the orbit of Mars at the end of January 2008. Currently, there is a 1-in-75 chance of the "Mars Crosser" hitting the Red Planet, and if it does, the 30,000 mile per hour speeding mass would generate a three megaton explosion (approximately the size of the terrestrial Tunguska impact over Siberia in 1908) and create a crater half-a-mile wide somewhere north of Meridiani Planum. So, the Mars Rover Opportunity will get a ringside seat should this once-in-a-thousand-year event occur…
NASA's Near-Earth Object Office at the Jet Propulsion Laboratory (JPL) in Pasadena, California reported this month that a known Near Earth Asteroid (NEO) will be crossing the path of Mars on January 30, 2008. This puts asteroid "2007 WD5" in a special group of asteroids: "Mars Crossers". NASA's Near Earth Object Observation Program (or "Spaceguard" program) is intended to track asteroids that come close to the orbit of Earth, but also provides data for any asteroids tracked near our planetary neighbors.
Scientists are both excited and concerned by the possibility of an impact on Mars. Whilst this is a once in a lifetime opportunity to observe an impact of this size on Mars (remember the excitement at Shoemaker-Levy hitting Jupiter in 1994?), this event would eject millions of tons of dust into the Mars atmosphere, interfering with the Mars Expedition Rovers, and hindering orbital imaging of the planet. The Phoenix mission (currently en-route) will undoubtedly be affected. Looking far into the future, this event could have serious consequences for manned exploration.
"Right now asteroid 2007 WD5 is about half-way between the Earth and Mars and closing the distance at a speed of about 27,900 miles per hour [...] Over the next five weeks, we hope to gather more information from observatories so we can further refine the asteroid's trajectory," – Don Yeomans, manager of the NEO Office at JPL.
Although the odds are low, and the asteroid is expected to miss Mars by 30,000 km, asteroid hunters will be keeping a close eye on the progress of 2007 WD5 as it barrels closer and closer to the Red Planet and our robotic explorers.
Source: Near Earth Object Program
Tags: asteroid, impact, MarsRelated stories on Universe Today
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December 29th, 2007 at 2:19 am
what about phobos and deimos?
December 29th, 2007 at 3:47 am
The chances of impact have since been upgraded to 3.9%, or 1 in 25 roughly. Should it occur, would an impact of this magnitude be visible from Earth with moderate equipment?
December 29th, 2007 at 9:59 am
If the Asteriod Misses Mars will there be a high chance of the Asteriod Impacting Earth?
December 29th, 2007 at 11:42 am
I think this is rather exciting should it happen , a great chance to observe an asteroid hit and outcome from close range. I think an awful lot could be learned from this that would far outway other science mission losses
December 30th, 2007 at 12:09 am
If the asteroid continues on its present course but with one or two minor modifications within the next few weeks, and then, upon approaching very close to Mars, is seen to adjust its behavior fairly radically (in that it puts out braking devices are alters its orientation to the planet's surface) and then lands very, very softly upon the surface of Mars—if all that is seen to happen, Dear Reader, then my question is:
Should we be jealous?
Oh oh.
[ j/k ]
December 30th, 2007 at 8:18 am
This is a great oppurtunity for us, because after the impact the bedrock of Mars will exposed and will make it easy for us. Material ejected would contain whatever is beneath the surface. So I think scientists should examine spectral signature of the ejected dust.
January 2nd, 2008 at 10:38 am
If the Asteroid Misses this time around, we should be asking and looking closely at thus question – whether it will hit Mars or not any time soon ?
January 3rd, 2008 at 6:03 am
I understand that an extrapolation of the orbit of 2007 WD5 shows that it poses no risk of hitting the Earth – but presumably a near miss of Mars would disturb the asteroid's orbit. I wonder if this would change that prediction?
January 5th, 2008 at 2:39 pm
What a pity Earth did not send its Earthling in time to observe and record the event, if it happens. What a lot of useful information might have been gathered to save the Earth in a similar event. Earthlings should hurry up and set a station as near as possible to observe. I wonder if Hubble would take photoes?
January 5th, 2008 at 10:29 pm
So, is it heading Sunward or Earthward past Mars or what?? Can we see it from the southern U.S on a crystal clear night? Where can we see a possible trajectory?
January 6th, 2008 at 7:20 am
well ive been looking and now its a 3.6% chance of impacting Mars it would be a Miracle* if it did infact impact Mars but im still wondering, if it does miss and get's affacted by Mars gravitional pull and changes it course…. i highly doubt it would impact us..right?
January 12th, 2008 at 9:39 am
[...] 1-in-75 Chance Of Tunguska-Size Impact On Mars [...]
January 13th, 2008 at 9:48 am
Indeed, it might be a great chance to observe an asteroid hit and many conclusions can be drawn from this , but honestly, 1:75 rate to happen is too small.
January 27th, 2008 at 4:52 pm
[...] all the excitement surrounding the possibility of asteroid 2007 WD5 hitting Mars and the concern of Near Earth Asteroid 2007 TU24 dropping to Earth, we now have something new [...]
January 27th, 2008 at 5:53 pm
[...] spy satellite After all the excitement surrounding the possibility of asteroid 2007 WD5 hitting Mars and the concern of Near Earth Asteroid 2007 TU24 dropping to Earth, we now have something new [...]
January 28th, 2008 at 10:02 am
hey sorry but now no good newses for our earth because thier will be to much of things which will efectto us also and the first is the water level will increse and will reach to much high that we could not image about it, it is said that the end of 2008 all space object will come nearer to each other and will after some 90 years and will finish the life of the full earth, the earth's all the satelities will be jamed because of the sun has a black spot and their too much of wind and rain is falling like anything so the veg. will be affected after no long the life will be present on earth.
Thank you,
for more e-mail me on vinod_pasnani@yahoo.com.