Celestia Forums

I have just read that a 100m asteroid, recently discovered, is passing very close to Mars on January 30th, and could even hit the planet (actually, close to Opportunity!). Wouldn't it be so cool?

I read it here: http://www.msnbc.msn.com/id/22350742/

Regards,

Guillermo

If it does hit, It would be really cool to see the hirise images from the impact site. About a foot per pixel resolution.
cartrite

^^ 2007 WD5

Currently a 1 - 75 chance. More observations should clear this up.

I get about 50,000 km using ephemeris from Horizons/JPL, wheeee!





cel://Follow/Sol:2007WD5/2008-01-30T09: ... 1200&ver=2

Sucks to be Mars, eh?

Well, if it hits, wonderful. If it doesn't, wonderful. I haven't decided which I would prefer. I guess a hit would be pretty cool. Asteroid impacts have a way of ruining one's day though, and it wouldn't be all to great for unforseen aspects of an impact to affect our operations there. i.e. debris flying into orbit, being a hazard to orbiring spacecraft.

I don't know if that's possible, but the thought came to mind.

Passing that close to Mars, how come nobody is asking about the possible change to its trajectory/orbit due to Mars' gravity? Will it be passing Sol-side or space-side (?terminology?)... or will that even matter at all?

I think somebody asked about tha ton the Bad Astronomy forum. The reply was something like "There are thousands of potentially hazardous asteroids, and you're going to worry about just one? If 2007WD5 misses Mars, you'll never hear a word from it again." I would potentially agree. The odds are low that the asteroid's orbit will be placed into an orbit that could result in an impact with anything. I'm not saying it's impossible though.

New info from NASA about the hit:

Mars Impact Probability Increases to 4 Percent
The impact probability for a collision of asteroid 2007 WD5 with Mars on January 30 has increased from 1.3% to 3.9%. Pre-discovery observations of asteroid 2007 WD5, taken on November 8, 2007 have allowed its orbit to be refined and the uncertainties for the late January Mars encounter have been improved. The impact probability resulting from the recent orbit refinement has increased to a surprising 3.9% (about 1 in 25 odds).

More info here:
http://neo.jpl.nasa.gov/news/news153.html

Update! 2 January:

New Observations Slightly Decrease Mars Impact Probability

Additional position observations for asteroid 2007 WD5 taken on December 29 through January 2 have been used to improve the accuracy of the asteroid's orbit. As a result, the range of possible paths past Mars has narrowed by a factor of 3 and the most likely path has moved a little farther away from the planet, causing the Mars impact probability to decrease slightly to 3.6% (about one chance in 28 ).

More info here:
http://neo.jpl.nasa.gov/news/news154.html

LordFerret wrote:Passing that close to Mars, how come nobody is asking about the possible change to its trajectory/orbit due to Mars' gravity? Will it be passing Sol-side or space-side (?terminology?)... or will that even matter at all?

I highly doubt that an asteroid of this size would do anything to mars itself except for making a nice new impact crater

if he hits - yay! give us some cool HD photos or even videos of it.
if it misses - where will it go?
this very close flyby would probably change is orbit quite a bit.

phoenix wrote:

LordFerret wrote:Passing that close to Mars, how come nobody is asking about the possible change to its trajectory/orbit due to Mars' gravity? Will it be passing Sol-side or space-side (?terminology?)... or will that even matter at all?

I highly doubt that an asteroid of this size would do anything to mars itself except for making a nice new impact crater

I'm rather certain he was asking about Mars' effect on the asteroid, not the other way around.

Oh no! Another update again

2007 WD5 Mars Collision Effectively Ruled Out - Impact Odds now 1 in 10,000
Since our last update, we have received numerous tracking measurements of asteroid 2007 WD5 from four different observatories. These new data have led to a significant reduction in the position uncertainties during the asteroid's close approach to Mars on Jan. 30, 2008. As a result, the impact probability has dropped dramatically, to approximately 0.01% or 1 in 10,000 odds, effectively ruling out the possible collision with Mars.

Full story here:
http://neo.jpl.nasa.gov/news/news156.html

I demand that NASA launch an emergency mission to mars to push the asteroid 2007 WD5 back on target.

I want see this happed in in real time.

This would be approximately the size of the impact. Basically a city killer. Talk about urban renewal.

http://www.meteorcrater.com/index.php
http://en.wikipedia.org/wiki/Meteor_Crater

Seriously, is anyone surprised? The odds were low anyway. Sure they were high compared to the usual near-miss, but we shouldn't be surprised.

Hungry4info wrote:Seriously, is anyone surprised? The odds were
low anyway. Sure they were high compared to the usual near-miss,
but we shouldn't be surprised.

No surprise at all here, but it really would be nice to see the actual
effects of a collision with this relatively small asteroid. Would be
very nice to obtain some data from which more general impact
information could be derived. Yes?

phoenix wrote:

LordFerret wrote:Passing that close to Mars, how come nobody is asking about the possible change to its trajectory/orbit due to Mars' gravity? Will it be passing Sol-side or space-side (?terminology?)... or will that even matter at all?

I highly doubt that an asteroid of this size would do anything to mars itself except for making a nice new impact crater

if he hits - yay! give us some cool HD photos or even videos of it.
if it misses - where will it go?
this very close flyby would probably change is orbit quite a bit.

That's exactly what I was wondering about (marked in red). All this discussion about the possibility of it hitting... should it not, it's going to pass very close. Mars's gravity only being 0.376 of Earth's (1.0), it should still have some kind of influence on this object. That's why I'm asking where will it be passing (inside its orbit or outside as it were)? Which direction will its altered trajectory swing?

Just curious.

LordFerret, The asteroid is one of the few that cross Earth and Mars, this is an incredibly high precision trajectory. If anything this will remove it as an Earth crossing asteroid. Don't get me wrong, it will still come into the inner solar system (closer to the sun then earth, but it would be out of alignment to hit Earth.

Unless I am misinterpreting what I see in Celestia, 2007 WD5's orbit does not cross Earth's, but it does come close. I would guess that the asteroid will be thrown into a trajectory that'll make it an Earth and Mars crosser.

Thanks MKruer, not that I was all that concerned about it with regard to Earth. I'll imagine then that its new orbital parameters are something which will not be known with any precision until after it is well past Mars and Mars' gravitational influence. That thought is based on something Fridger just recently mentioned about the complexities involved in n-body calculations. I'm sure this object will be watched now for some time to come. It will be interesting to see what becomes of it.