Not mundane or pointless, but I couldn’t figure out a better place to post this.
I didn’t know about this until Neil DeGrasse Tyson mentioned it on The Colbert Report, but an asteroid “roughly as long as a tennis court” passed closer than the moon at about 10:06 pm EDT tonight. Story here.
It’s the third close call this year!
Where are those oilriggers in spaceships with nuclear weapons when you need them?
Happens all the time. No big deal. See http://www.spaceweather.com they have a chart of close approaches at the bottom of the page, every day.
Is that supposed to make us feel better?
I thought I felt a bit of a draught.
It can be kind of scary to be up-to-speed on what is going on ‘out there’. Especially when you stand under a night sky and see meteors now and then, and realize that one of these days…BOOM! Its just gotta happen (again).
Better to just let the telescope-guys stand guard, but IMO, we could use a better set-up for detection/prevention 
So, I guess I’m going to have to complete that project at work today after all… :mad:
In space no one can hear you woosh.
Of course, the normal “shooting star” meteors you see are only sand or gravel-size…
Yeah, but get one of those in your eye and it’s no laughing matter!
Space’ll shoot your eye out!
Sounds like it would mostly just be terrifying rather than devastating (relative to some our more recent natural disasters).
So just how big does one have to be before it actually hits the ground and sets off the Yellowstone volcano?
That I don’t know, and I don’t think anybody does.
The number I’ve heard quoted for causing global, rather than merely local, effects (presumably ignoring scenarios like setting off supervolcanoes or being mistaken for a nuclear weapon) is 1 km in diameter. An asteroid smaller than that hitting Earth could cause devastating damage on a local scale, or tsunamis that would spread over the oceans as tsunamis do, but wouldn’t cause a global impact winter.
How big an asteroid would have to be to hit the ground would depend on the composition of the asteroid. Iron meteorites the size of marbles have been found.
The Impact Calculator will give you typical effects for a variety of bolides impacting the planet. Ballpark, it has to be ~ a mile wide for truly nasty global effects. Of course, Tunguska was very unpleasant for those within 30 miles, and I think the latest dope on the rock that caused it was that it was around 50 meters across.
Comets move a lot faster than your garden variety meteoroid, and consequently hit a lot harder. Niven and Pournelle’s “Lucifer’s Hammer” is an excellent fictional account of Earth getting walloped by a several mile across comet. (Do your best to get through the very dated sociology and author pulpit-thumping. The Hot Fudge Sundae scene, OTOH, is not to be missed)
I’m not sure I follow how that means anything. Presumably, whatever the size limit, an asteroid just bigger than that limit would likely shrink to something marble-sized by the time it hit the ground, whether that turned out to be a Tangerine or Texas.
You can pretty much quit reading it after the part where the comet hits and
Tim Hamner joins the Stronghold The good part is before that.
Here ya’ll go, cracking me up at work.
I am such a Neil Degrasse Tyson groupie. I loved that Colbert nearly broke character on this episde. He seemed eager to show off how knowledgable he was about science. Ha. Loved that.
I always get excited when I hear about near misses, too. Gives me shivers when I daydream about what it would be like if we really did get hit in a way that had a huge impact.
Wellll, no. But it helps you get used to the danger… 
They are, and there are some very good projects running now. Google for LINEAR. There are several other projects running, too. Used to be amateurs discovered all the new comets. Now, an amateur hardly gets a chance, before the LINEAR guys get them. Now if an amateur wants to get a comet, he goes looking thru the newest LINEAR data. But he doesn’t get his name on it. The LINEAR project does. 
http://neo.jpl.nasa.gov/ NASA keeps you up to date on your future death. They give you size, speed and date you will die. Your tax dollars at work.
Even better than my link. I had to bookmark this one. BTW, one of those was discovered by the LINEAR project I mentioned.