question about the Russian meteorite hit

[Divine Discontent]

was this one so small that they didn't know it was coming (like they do the one that will be a near-hit very soon), despite reports I've read that said it might have been 10 tons itself? I guess so, but I wanted anyone's thoughts on this that may know about meteors. If the one that will be a near-hit were to slam into the Earth, it would possibly kill millions, yes?

[JI7]

1. the other one is an asteroid isn't it ?

i think we don't know about meteors until they hit but they are smaller than asteroids. with asteroids they are larger and we can see them further away.

someone else should be able to clear it up more. i'm kind of confused myself.

[Warpy]

2. I'd think most of what hit the ground was pretty small

This thing pretty much blew itself up, making me think it was mostly ice.

I know all the injuries there were cited as being from flying glass broken by the shock wave, not high speed rocks.

It will be interesting to find out what the meteorite hunters find on the ground outside town.

What amazes me is how bright this thing was. Most of the fireballs that come in aren't visible during the day. This one looked as bright as sunlight.

Noisy bugger, too, blast followed by a couple of sonic booms were on one of the videos.

[longship]

4. They definitely sounded like sonic booms, didn't they.

I thought so, too. Not surprising from the reports of broken windows, etc. classic sonic boom results.

[Tree-Hugger]

8. It was

Sonic booms are not uncommon with bolides. The smoke trails are normal for them as well.

[longship]

12. I've seen several of them.

Once, while watching the Perseid meteor shower in the Mojave, a rather large bolide streaked through the sky. It made a sound similar to sizzling bacon. Amazing. No sonic boom, though. The trail lit up in all sorts of colors as it zoomed across the sky. I'll never forget that one.

[Tree-Hugger]

14. Same here

I heard hissing from one years ago. It was so cool. I thought I was hearing things. I put up a link further down this thread that explains the two types of sound that can occur. One is the hissing and crackling sound and the other is the sonic boom.

[Fumesucker]

7. The average meteorite velocity is from 20 to 70 kilometers per second

Mach one is 340 meters per second.

That means meteors are doing anywhere from Mach 30 over 100.

Sonic boom it was.

[Warpy]

15. No, it blew apart over Chelyabinsk.

The sound was detonation followed by two distinct sonic booms.

[blkmusclmachine]

3. Seems like we're flyin' blind sometimes.

[Fumesucker]

5. Anything big enough to see in advance with our current capabilities is a mega killer

Most space rocks are dark colored, the distances are vast and the only means we have of finding them is from reflected sunlight or possibly the fact that they are slightly warmer than the background of deep space.

[hobbit709]

11. Exactly. If it's big enough to be seen, it's big enough to do a major whomp.

[doc03]

6. John McCain has called for an investigation on this, what did Obama have to with

it and why didn't he stop it?

[Tree-Hugger]

9. +1 nt

[KharmaTrain]

10. We're Constantly Pelted With Space Debris...

...it's how many scientists believe water and life came to be on this planet. There are tons of space rocks and ice that hit our atmosphere each year...most burns up long before it gets to the lower atmosphere...and those that do survive that far burn up just like in that video. It's actually quite natural...one hell of a light show.

Since the earth is 75% water and there are many areas...such as the Poles and desert regions that are sparsely populated...we rarely get to view these events. This is a classic "shooting star". We've launched tons of junk weighing 10 tons or more that regularly fall back to earth. NASA claims they track them...but it's a proverbial needle in a cosmic haystack.

[Tree-Hugger]

13. Not an asteroid

This was a meteorite. We can predict meteor showers as we move through debris fields. Individual little guys aren't really predictable.

This was a large fireball known as a bolide. Thecearth gets over a thousand of these a day, but they generally go unnoticed as they are not as bright as this one. The smoke trail and delayed sonic boom are normal for this kind of thing.

There is a lot of misinformation on the net about this thing right now. I have been passing around a link with more information.

http://www.amsmeteors.org/fireballs/faqf/