INCOMING! (An asteroid, that is... tonight!)

[Astroboy14]

See the story here.

I hope someone in the Sudan has a video camera handy!

[Astroboy14]

Fine! No one but me cares… and it’s too late now anyways.

Woulda been cool though, if you were in the Sudan…

[Santo_Rugger]

Great username/thread combo, if nothing else.

I do wonder how they arrive at their TNT equivilancy number, though. Any idea?

[Zebra]

Are we going to Addis Ababa Mr. Luthor?!?!?

[Astroboy14]

Serious answer: no idea.

I’m betting it’s just a guess, since obviously there’s no way of telling the composition of the asteroid. It could be rock, or it could be nickle-iron; I think the results would be different, so they just averaged them out and estimated. I could easily be wrong on that though… not current on my asteroids…

[Chronos]

I do wonder how they arrive at their TNT equivilancy number, though. Any idea?

It’s pretty straightforward. They can estimate the size from the brightness, and take an educated guess as to the density (a few times that of water, for a chondrite, or up to almost 8 for an iron one), which gives them a rough value for the mass. The same orbital data that they used to tell them it was going to hit also tells them the speed. From there, it’s just a matter of KE = 1/2 m*v[sup]2[/sup], and convert the energy units to TNT equivalency.

[Astroboy14]

@Chronos

It’s pretty straightforward. They can estimate the size from the brightness, and take an educated guess as to the density (a few times that of water, for a chondrite, or up to almost 8 for an iron one), which gives them a rough value for the mass. The same orbital data that they used to tell them it was going to hit also tells them the speed. From there, it’s just a matter of KE = 1/2 m*v[sup]2[/sup], and convert the energy units to TNT equivalency.

EXACTLY what I was trying to say in my prior post.

Yeah.

[Ale]

@Astroboy14

Serious answer: no idea.

I’m betting it’s just a guess, since obviously there’s no way of telling the composition of the asteroid. It could be rock, or it could be nickle-iron; I think the results would be different, so they just averaged them out and estimated. I could easily be wrong on that though… not current on my asteroids…

I think it’s made of TNT…

[Squink]

@Chronos

They can estimate the size from the brightness

What’s the albedo of cold neutronium? :dubious:

[Frodo]

@Squink

What’s the albedo of cold neutronium? :dubious:

We’ll have to ask Quagdop the Mercotan, i think.

[Squink]

Earth Impactor 2008 TC3 en route to Northern Sudan

The above image is a small section from a much larger image, exposed while asteroid 2008 TC3 entered Earth’ shadow about one hour before expected atmospheric impact over northern Sudan. The image was made with one of La Sagra Sky Survey’s (LSSS) 45-cm f/2.8 telescopes. It is a six minute exposure tracked at siderial rate. Exposure start time was 2008 Oct. 07, 01:45:23 UT. The section shows a field which is half a degree wide, comparable to the size of the full moon. The asteroid moved from west (right) to east (left). At start of exposure it was at a distance of 29600 kilometers, approaching at a speed of 7.61 kilometers per second. The periodic light variation along the early part of the trail indicates a fast rotation of the intruder around its spin axis. Long before the exposure ended, the trail got dimmer and completely invisible, confirming the predicted time of entry into Earth’ shadow.

[detop]

So, What kind of <insert your choice here> end of the world creature, invader from outer space, angelic visitor, etc. </insert> did it release ?

[Squink]

There seems to be no news coming out of northern Sudan tonight.

:eek:

[garygnu]

You can practice defending the Earth here.

[KneadToKnow]

@Zebra

Are we going to Addis Ababa Mr. Luthor?!?!?

Excellent!

I can’t frakking believe someone beat me to that.

[Squink]

Impact of Asteroid 2008 TC3 Confirmed

Confirmation has been received that the asteroid impact fireball occurred at the predicted time and place. The energy recorded was estimated to be 0.9 to 1.0 kT of TNT and the time of detection was 02:45:45 on October 7 (Greenwich Standard Time).

[ftg]

Presumably several real and “non-existent” satellites tracked it’s entry in order to collect data. We might finally have some asteroid impact data to compare to the mysterious Vela Incident.

[Squink]

The full story of Earth-impacting asteroid 2008 TC3 - The Planetary Society Blog

I have received confirmation that a KLM airliner, roughly 750 nautical miles southwest of the predicted atmospheric impact position, has observed a short flash just before the expected impact time 0246 UTC.
…
A very preliminary examination of several infrasound stations proximal to the predicted impact point for the NEO 2008 TC3 has yielded one definite airwave detection from the impact. The airwave was detected at the Kenyian Infrasonic Array, (IMS station IS32), beginning near 05:10 UT on Oct 7, 2008 and lasting for several minutes.