Comments on: Another tiny rock will pass Earth tomorrow

By: Vetr

Vetr — Thu, 31 May 2012 11:18:22 +0000

I think, if it had been up to me, I might have called it something that didn’t include ‘KT’.

By: Matt B.

Matt B. — Wed, 30 May 2012 18:25:55 +0000

@0 Phil: I think you’re missing the word “hit” in the fourth to last paragraph–”but the odds of getting hit by one are so small they’re basically zero.”

By: smittypap

smittypap — Tue, 29 May 2012 21:17:25 +0000

Thanks for keeping us updated, Phil. Passing a large stone is never easy.

By: Kevin in Sacramento

Kevin in Sacramento — Tue, 29 May 2012 18:51:28 +0000

An impact by 2012 KT42 would produce an upper atmosphere air burst equivalent to 11 kt TNT, roughly equal to Hiroshima’s Little Boy. The asteroid would be vaporized as these small impacts occur approximately once per year. A comparably-sized object caused the Sutter’s Mill meteorite in California on 2012 April 22.

By: Uncle Al

Uncle Al — Tue, 29 May 2012 17:15:13 +0000

“this rock is way too small to do any damage” , Yeah – “too small.” An iron ball 10 meters in diameter masses 4100 tonnes. Give it a meager 5 miles/second. KE = (mv^2)/2, plus mgh. 4.186×10^12 J/kt

[(4.1x10^6 kg)(8.047x10^3 m/sec)^2][(2)(4.186x10^12) = 31 kilotonnes

By: Pete Jackson

Pete Jackson — Tue, 29 May 2012 12:55:00 +0000

Just picked up on my subspace radio – the tiny inhabitants of a small space rock have recently been most alarmed at seeing the third planet from the Sun, always just a pin-point of light, suddenly grow in size and is now looming over them as an enormous menace. Fortunately, these inhabitants, living in such a harsh environment, have developed enormous technological capabilities to cope, and have already devised a solution to their peril. Their plan is simply: NUKE THE EARTH!

By: Marc

Marc — Tue, 29 May 2012 10:13:11 +0000

@6,

We are all going to die much earlier. More like within 130 years considering that the oldest person is not much more than 120 years.

By: puppygod

puppygod — Tue, 29 May 2012 07:28:59 +0000

With all these asteroids missing the Earth, I can’t help but feel unloved. We’re a perfectly nice planet, why don’t they want to hit us?

It is because we have too shallow gravity well, isn’t it? Aw, shucks. Now I have a small gravity well complex.

By: Messier Tidy Upper

Messier Tidy Upper — Tue, 29 May 2012 04:15:33 +0000

@2. BeerMe : “Phil, do these asteroids pose risks to our space hardware?”

A very, very, *very* exceedingly remote one for satellites and space stations that cannot move out of the way quickly enough just possibly.

To add to what (#10.) Blargh said, most working satellites and the International Space Station are capable of shifting their positions using thrusters and thus can avoid anything large enough to cause serious damage.

The ISS has in fact been forced to take evasive action to dodge space junk on occassion. When a particularly worrisome piece passes close by the crew can be forced to take shelter in the Soyuz capsule which could return them to Earth if the Station was too badly hit. (See for example the article linked to my name here.)

A dead satellite that’s out of fuel or otherwise unable to be controlled may be hit one day – and in a chain reaction could well multiply the amount of space junk up there but given the relative size of the satellites versus the sheer amount of space in, well, space, its highly unlikely to happen for a very long period of time.

By: Messier Tidy Upper

Messier Tidy Upper — Tue, 29 May 2012 03:55:17 +0000

This story reminds me of the recent (non)scares of falling satellites.

Like them, if these very small asteroids did hit Earth – which they won’t – odds are pretty high that it would land in one of the oceans or in a desert area.

Mind you, in some ways for a small asteroid making a big splash and a consequent tsunami is actually more of a problem than a land landing would be! Pretty sure their mass, speed and thus kinetic energy being transformed into heat, light and shockwave is considerably greater than any artificial satellite we’ve yet built – even the ISS.* Right?

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* Which, btw., like Mir, Skylab and the Salyuts is hollow and would break up on re-entry.