Asteroid Threatens to Hit Mars

December 21, 2007 Mars

Astronomers funded by NASA are monitoring the trajectory of an asteroid named 2007 WD5 that is expected to cross the orbital path of Mars early next year. Calculations by NASA's Near-Earth Object Office at the Jet Propulsion Laboratory indicate that the 164-ft wide asteroid may pass within 30,000 miles of Mars at about 6 a.m. EST on Jan. 30, 2008.

"Right now asteroid 2007 WD5 is about half-way between the Earth and Mars and closing the distance [to Mars] at a speed of about 27,900 miles per hour," said Don Yeomans, manager of the Near Earth Object Office at JPL.

There is a 1-in-75 chance of 2007 WD5 hitting Mars; researchers can't be more confident than that because of uncertainties in the asteroid's orbit. If this unlikely event were to occur, however, the strike would happen somewhere within a broad swath across the planet north of where the Opportunity rover is.

"We estimate such impacts occur on Mars every thousand years or so," said Steve Chesley, a scientist at JPL. "If 2007 WD5 were to thump Mars on Jan. 30, we calculate it would hit at about 30,000 miles per hour and might create a crater more than half-a-mile wide." The Mars Rover Opportunity is currently exploring a crater approximately this size.

Such a collision could release about three megatons of energy. Scientists believe an event of comparable magnitude occurred here on Earth in 1908 in Tunguska, Siberia, but no crater was created. The object was disintegrated by Earth's atmosphere before it hit the ground, although the air blast devastated a large area of unpopulated forest. The Martian atmosphere is much thinner than Earth's so a similar sized impactor would be more likely to reach the ground.

Asteroid 2007 WD5 was first discovered on Nov. 20, 2007, by the NASA-funded Catalina Sky Survey and put on a "watch list" because its orbit passes near the Earth. Further observations from both the NASA-funded Spacewatch at Kitt Peak, Ariz., and the Magdalena Ridge Observatory in New Mexico gave scientists enough data to determine that the asteroid was not a danger to Earth, but could potentially impact Mars.

Because the asteroid has been tracked for little more than a month, there is still some uncertainly about the path it will take. "Over the next five weeks, we hope to gather more information from observatories so we can further refine the asteroid's trajectory," says Yeomans. More data could eliminate or confirm the possibility of an impact.

Source: NASA


print this article email this article download pdf blog this article bookmark this article     Stumble it Digg this share on Facebook retweet share on Reddit add to delicious
Rate this story - 4.6 /5 (33 votes)

Rank Filter

Move the slider to adjust rank threshold, so that you can hide some of the comments.


Display comments: newest first

  • Ashibayai - Dec 21, 2007
    • Rank: 4 / 5 (3)
    A fresh impact crater would make a very interesting site for a mars rover...
  • ShadowRam - Dec 21, 2007
    • Rank: 1 / 5 (1)
    ^^ Very very true
  • quantum_flux - Dec 21, 2007
    • Rank: 1 / 5 (1)
    I don't find it ethical to be excited about a large asteroid impacting the Moon or Mars. Mars has a really bad dust-storm problem as it is, and that could only be made worse by a gigantic crator impact which would lead to exponentiating nuclear winter conditions. The thing is that the Moon and Mars are some of mankind's future assets (terraforming should begin within 80 years) and thereby they should to be protected and maintained if at all possible. I know that's simply not possible right now, but the mindset should be adopted pronto.
  • axemaster - Dec 22, 2007
    • Rank: 3 / 5 (1)
    Uh, quantum, how is there going to be a nuclear winter on Mars when there is barely enough atmosphere to hold any dust up? The dust will go up, there'll be a cloudy day or two (24 hour days), and then most will fall down again. Besides this is only a relatively small asteroid; as they say it is the same as the one that hit Siberia. Sure there'll be some damage, but nothing significant in the long term.

    -Axemaster

December 21, 2007 all stories

Comments: 4

4.6 /5 (33 votes)
  • Stumble this up

  • Digg this

  • share this

  • hide
  • Related Stories




  • hide
  • Relevant PhysicsForums posts

  • The shape of our solar system's orbits.
    created Nov 07, 2009
  • Above or Below the Line of Nodes
    created Nov 07, 2009
  • Supernova vs. Nova?
    created Nov 07, 2009
  • Supernova's Gamma Rays and Comets
    created Nov 06, 2009
  • More from Physics Forums - General Astronomy

Other News

Deep creep means milder, more frequent earthquakes along Southern California's San Jacinto fault

Deep creep means milder, more frequent earthquakes along Southern California's San Jacinto fault

Space & Earth / Earth Sciences

created 18 hours ago | popularity 4.5 / 5 (4) | comments 0

With an average of four mini-earthquakes per day, Southern California's San Jacinto fault constantly adjusts to make it a less likely candidate for a major earthquake than its quiet neighbor to the east, the ...


Success in 'space elevator' competition (AP)

Success in 'space elevator' competition (Update 3)

Space & Earth / Space Exploration

created Nov 05, 2009 | popularity 4.3 / 5 (33) | comments 50

(AP) -- A robot powered by a ground-based laser beam climbed a long cable dangling from a helicopter on Wednesday to qualify for prize money in a $2 million competition to test the potential reality of the ...


In a Galaxy Far, Far Away...

In a Galaxy Far, Far Away...

Space & Earth / Astronomy

created Nov 06, 2009 | popularity 4.8 / 5 (5) | comments 17

(PhysOrg.com) -- Astronomers have published the discovery of the farthest known object in the cosmos: a star that exploded when the universe was only 630 million years old -- only 4.6% of its current age. ...


'Dropouts' pinpoint earliest galaxies

'Dropouts' pinpoint earliest galaxies

Space & Earth / Astronomy

created Nov 06, 2009 | popularity 4.2 / 5 (10) | comments 13

Astronomers, conducting the broadest survey to date of galaxies from about 800 million years after the Big Bang, have found 22 early galaxies and confirmed the age of one by its characteristic hydrogen signature ...


Space hotel taking bookings for 2012 opening

Space hotel taking bookings for 2012 opening

Space & Earth / Space Exploration

created Nov 05, 2009 | popularity 4.4 / 5 (21) | comments 11

(PhysOrg.com) -- The first orbiting space hotel is on track to open for its first customers in 2012, but hurry, as bookings are filling fast.