Posted on 05/03/2014 5:11:16 PM PDT by SunkenCiv
Don't worry, NASA's known about it for ages. Like, four whole days.
So here’s a fun fact: while you were sleeping last night, you had a near-death experience. Yes, you – and everyone else on this lovely planet. In the wee hours of the morning, a pretty sizeable asteroid soared by the Earth, just missing it. But we’re okay. For now.
At 4:13am EDT, asteroid 2014 HL129 essentially side-swiped the Earth, coming within 186,000 miles of our planet. For reference, the moon is 238,855 miles away. Which means the asteroid was much, much closer to us than the moon will ever be. And the moon is pretty damn close. Like, we-sent-people-there-in-the-’60s close.
Oh, and why is it called “2014 HL129?” It’s because we pretty much just discovered that this asteroid exists. Yep, a rock that NASA’s Asteroid Watch says was about 25 feet wide (approximately the size of a bus) and came within space-moments of smacking our planet around was completely unknown until April 28th. Four days ago. But no big deal guys, no need to panic. We’re fine.
Just know planet-wide destruction could be under a week away and we could have no idea. Neato.
(Excerpt) Read more at geekosystem.com ...
Larger, but hollow.
No, not from a 25 foot one, from a larger one capable of causing massive destruction — as noted above, he’s talking about the short time frame between detection and encounter.
Ah...that would make a difference, I suppose.
Yeah, that’s close and if it impacted, depending where there would be a lot of damage and possible loss of life, again depending on where it hit. But ‘’planet-wide destruction’’ from something the size of a bus? No. A mile or more across, yeah, definitely would be a very bad day on Planet Earth but not something on the order of this object.
25 feet wide would be a “big-bada-boom” but not a threat to the entire planet.
If that asteroid missed us by 186,000 miles this time, is it possible that it would hit us on the next swing by?
the damage caused by a meteor depends on its composition
:’) A rock perhaps a quarter mile across would do that, by how much would depend on where it hit, velocity, mass, and composition.
Quite right. If it detonated (like the Russian rock from a year or so ago) over a major city, damage would be in the billions, and there would almost certainly be people killed.
Didn’t he win the Oscar for that role? ;’)
I believe his reference to planet-wide destruction wasn’t referring to a 25 foot object; he was pointing out that an object large enough to cause that kind of damage could show up with no or inadequate warning, just as this little dust speck did.
Thanks, I failed to address that part of the post and only considered the size of the impactor. I have heard that something approaching from sunward is the worst case, the glare masks larger asteroids very well.
We spot them better. Recently we weren’t looking for anything this small.
Until about 25 years ago, there was almost no detection system at all; objects of this kind were found quite by accident during surveys of the sky in search of comets. Until 1994, there was a really stubbornly stupid streak among many astronomers, who insisted that looking for these was a waste of time, because the consequences of impact were very nearly zero due to the small size.
In 1994 the SL-9 comet fragments smacked one after another into Jupiter, leaving Earth-sized scars in that planet’s atmosphere. That sobered people up something wonderfully. I’d be surprised if some of those old blowhards didn’t have nervous breakdowns and have to retire from that experience, just as happened after the ascendancy of the Alvarez model for mass extinctions became widely accepted (except in Darwin-mired England).
The SL-9 discovery was a small independent project consisting of three people (the Shoemakers, and David Levy) using a largish small reflector (or maybe it’s a Schmidt-Cassegrain) up on Mount Palomar. They spent night after night searching for (and finding) Earth-crossing asteroids; Carolyn Shoemaker still has the record I believe for most comet discoveries by a single, live person (the overall record is held by an automated orbital telescope).
Spacewatch (or is it called Spaceguard?) started sometime prior to that, I think in Australia, and it started as a small operation, gradually bringing other low-budget independent operations around the world into a network, and all searching for nearby potential threats. Budgets rose after the SL-9 impacts.
The short answer is, both — more efforts are made to find them, and therefore there’s an apparent increase in the number coming by. The fact is, any fluctuations in number of arrivals is quite random, and the big increase over the last couple of decades is due to the systematic search for them. They were there before, just like Antarctica’s ozone hole or extrasolar planets, but no one had ever noticed them before.
Not only hollow, but the walls are pretty thin. The ISS would not burn up quite as thoroughly as the Skylab did. Oddly enough the only large piece of the Skylab that made it to ground was a fiberglas tank — I’ve got a chunk of that certified by NASA and attached to a poster of Skylab, given as a gift for memberships of the Space Society back then.
NASA probably will have that info by this time next year, when they’ve got enough observations of the object to calculate its ephemeris. These little pieces of space shmutz sometimes get the old come-hither from the Earth and burn on in; more often they cross our path when we don’t happen to be around.
The one in Russia was larger, and obviously didn’t miss. :’) Twice the diameter means 8 times the size (2x, 3 dimensions).
http://www.freerepublic.com/focus/bloggers/2989088/posts
http://www.freerepublic.com/focus/news/3088302/posts
http://www.freerepublic.com/tag/chelyabinsk/index
videos:
http://www.freerepublic.com/focus/chat/2988812/posts
http://www.freerepublic.com/focus/news/2988894/posts
http://www.freerepublic.com/focus/chat/2988950/posts
http://www.freerepublic.com/focus/chat/2989002/posts
Soviet-style agitprop from the immediate aftermath:
http://www.freerepublic.com/focus/chat/2988836/posts
http://www.freerepublic.com/focus/chat/2988896/posts
http://www.freerepublic.com/focus/bloggers/2988756/posts
http://www.freerepublic.com/focus/news/2988776/posts
My Dad worked for bell labs, and MANY years ago he brought home a piece of the material that was used to make Echo 1, the USA’s first telecommunications satellite (Before even Telstar!)
He made a bet with me that i couldn’t rip it, but I worried that thing for three straight days and finally won the bet!
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