INCOMING!, Detection and observation of Earth-approaching asteroids. Options

[ugordan]

Am I the only one who WANTS another to hit? (though obviously below a size limit where damage might occur)

Guilty here...

[SFJCody]

Same. If it's under 20m in diameter bring it on!

[SolarSystemRubbl...]

As seems to happen with the tiny close approach asteroids, the observation count for 2010 TD54 is skyrocketing. Already 62 obs in 2 days with a late evening update. (Sentry data, NEODyS has not updated)

The close approach time has advanced 2 minutes to 10:49 UTC tomorrow, Oct 12 (A bit less than 8 hours from now)

The distance is reduced a bit, to (nominal distance) 51,789 km (32,180 miles) from the earth's center, or about 45,420 km from the surface. Minimum distance (1 sigma) is about 75 km less. 0% chance of impact.

Number of listed close approaches to other objects have increased. Passes about 1 LD from the moon 2 hours after earth CA. Venus in November this year and 2016, Vesta in 2029, Earth in 2055,2057,2068, and 2126, Mars in 2071 and 2127, and Venus in 2129 and 2135. Obviously, they are manually running the projection past the normal Sentry automatic 2110 cutoff.

[dilo]

Thanks for this update, SolarSystemRubble!
Any new information on object physical characteristics? (size, rotation, etc)?

[SolarSystemRubbl...]

Size (estimated from H=28.8) would be expected to be 4-10 meters, but that's a guess based on assumed albedo. Any rotation data would take a bit of time to be analyzed, and since was only discovered 48 hours ago, obs are coming in hot and heavy. About 80 minutes to close approach (will pass over southeast Asia, from what I've read)

[SolarSystemRubbl...]

2010 TD54 including 76 observations through 01:50 UT.

No change to timing (10:49 UTC, about 40 minutes from now) or nominal distance (51,789 km from earth center). Uncertainty in CA distance reduced to 51 km.

Future close appoaches trimmed.

Moon, 2 hours after earth CA, 317,000 km

Venus Nov 9 (Sentry only) 0.09 AU
Venus 2016 (Sentry only) 0.07 AU
4 Vesta 2029 (Sentry and NEODyS) 0.02/0.03 AU
Mars 2030 (NEODyS only) 0.02 AU
Earth 2033 (NEODyS only) 0.11 AU
Earth 2044 (Sentry and NEODyS) 0.10 AU
Earth 2046 (Sentry only) 0.41 AU
Earth 2068 (NEODyS only) 0.07 AU

[SolarSystemRubbl...]

In response to the earlier question about rotation; if you look at the second video, you can see there is a periodic light curve, so with a little time some shape and rotation estimates will be possible.

http://www.universetoday.com/75564/video-a...close-to-earth/

Just a rough estimate, I'd say about a 30 second peak to peak light curve.

[hendric]

Any comments that this might be a spent rocket stage of some sort?
I love the fact that soon we'll be able to detect these early enough and figure out where to fly for one HELL of an awesome fireball.

[Paolo]

Any comments that this might be a spent rocket stage of some sort?

from the latest orbital elements the perihelion is at 0.68 AU and aphelion is at 2.89 AU. artificial objects tend to have one of the two close to Earth's orbit because that is the less "expensive" way to place something in orbit around the Sun.
I am quite sure that this is a natural rock

[brellis]

soon we'll be able to detect these early enough and figure out where to fly for one HELL of an awesome fireball.

Amusing to think of a bunch of folks waiting for an incoming meteor like SF Giants baseball fans in McCovey Cove in their kayaks, waiting for a home run!

[stevesliva]

from the latest orbital elements the perihelion is at 0.68 AU and aphelion is at 2.89 AU. artificial objects tend to have one of the two close to Earth's orbit because that is the less "expensive" way to place something in orbit around the Sun.
I am quite sure that this is a natural rock

Would all the early space-age probes that flew by Venus still have a 1 AU aphelion?

[dmuller]

Would all the early space-age probes that flew by Venus still have a 1 AU aphelion?

Probably not, but ... I'm speculating here ... raising aphelion from 1AU to 2.8AU (half-way to Jupiter) with accidental (i.e. non-targeted, non-planned) gravity assists at Venus seems a stretch. Galileo needed a well-planned Venus AND Earth flyby to raise its aphelion to 2.8AU-ish. IIRC early Soviet probes to Venus had a strongly type 1 (or 2 ... always mix them up) trajectory, trying to get there faster than a Hohman transfer, but I don't think their aphelions were far beyond Earth.

[jasedm]

Same. If it's under 20m in diameter bring it on!

It would be great to have a ringside seat for a nearside moon impact of something of this size (or bigger), a bit scary being underneath something headed for earth though.

Incidentally, an interesting calculator of local and global effects of impactors can be found here

It's a program whereby you can enter different parameters for the incoming body (size, density, velocity etc) and the program generates information on the impact effects.

Ghoulish, but fun..

[Holder of the Tw...]

A small rock (about four feet across, or a meter to a meter and a half) just skimmed by the earth. It was spotted and tracked several hours before closest approach.

JPL report link

[tasp]

Interesting.

A ring side seat watching an object shift from an Apollo asteroid orbit to an Aten class.

60 degree deflection upon encountering earth's gravity!