An Asteroid Passed By Earth At About Half the Distance Between Our Planet and Moon (smithsonianmag.com)

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An Asteroid Passed By Earth At About Half the Distance Between Our Planet and Moon (smithsonianmag.com)

Posted by BeauHD on Tuesday January 10, 2017 @07:00PM from the close-call dept.

On Monday at 7:47 A.M. EST, an asteroid thought to be between 36 and 111 feet wide passed roughly 120,000 miles from Earth -- and astronomers didn't spot it until Saturday. Smithsonian reports: According to astronomer Eric Edelman at the Slooh Observatory, 2017 AG13 is an Aten asteroid, or a space rock with an orbital distance from the sun similar to that of Earth. AG13 also has a particularly elliptical orbit, which means that as it circles the sun it also crosses through the orbits of both Venus and Earth. Lucky for us, 2017 AG13 wasn't a planet killer; according to Wall, the asteroid was in the size range of the space rock that exploded in Earth's atmosphere over Chelyabinsk, Russia, in February, 2013. According to Deborah Byrd at EarthSky, that meteor exploded 12 miles in the atmosphere, releasing 30 times the energy of the Hiroshima nuclear bomb. Not only did it break windows in six cities, it also sent 1,500 people to the hospital. That meteor also came out of the blue, and researchers are still trying to figure out its orbit and track down its origins. While 2017 AG13 would have caused minor damage if it hit Earth, the close call highlights the dangers of asteroids.

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Giant meteor 20?? by Anonymous Coward · 2017-01-10 19:08 · Score: 2, Funny

Once again inanimate rock you have failed us you helped out the dinosaurs god really does hate us
1. Re:Giant meteor 20?? by Black+Parrot · 2017-01-10 20:03 · Score: 2
  
  Once again inanimate rock you have failed us you helped out the dinosaurs god really does hate us
  By no means. This is just God's way of reminding us not to get caught doing what the dinosaurs got caught doing.
  
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  Sheesh, evil *and* a jerk. -- Jade
2. Re:Giant meteor 20?? by MitchDev · 2017-01-11 02:57 · Score: 2
  
  I voted for "Extinction Event Asteroid" in 2016....
meteor also came out of the blue by xxxJonBoyxxx · 2017-01-10 19:28 · Score: 2

>> meteor also came out of the blue

There is no blue...in SPAAACE!
a space rock with an orbital distance from the sun by xxxJonBoyxxx · 2017-01-10 19:29 · Score: 4, Funny

>> a space rock with an orbital distance from the sun similar to that of Earth

Presumably, that's why it almost hit us.
Re:Minor damage by hcs_$reboot · 2017-01-10 19:49 · Score: 4, Insightful

In what world does 30 times the energy of Hiroshima qualify as "minor damage"?
in the world where it explodes 30 times higher in the sky than the Hiroshima bomb.

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Re:Minor damage by hcs_$reboot · 2017-01-10 19:50 · Score: 3, Insightful

(and without radioactivity)

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Re:Minor damage by adjustinthings · 2017-01-10 19:57 · Score: 2

Hiroshima was actually a rather small nuclear bomb. Bombs even 1000x stronger have been tested and guess what, we're still here. http://www.tsarbomba.org/image...
Re:Minor damage by EvilSS · 2017-01-10 20:08 · Score: 5, Insightful

In what world does 30 times the energy of Hiroshima qualify as "minor damage"?
in the world where it explodes 30 times higher in the sky than the Hiroshima bomb.
In a world where larger asteroids could wipe out most complex life on this planet, a rock "only" big enough to destroy a city is still pretty minor.

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Speed in Furlongs per Fortnight ? by Anonymous Coward · 2017-01-10 20:22 · Score: 2, Insightful

36 feet wide, 120,000 miles ?!
GROW UP.
1. Re:Speed in Furlongs per Fortnight ? by Dog-Cow · 2017-01-10 21:22 · Score: 2
  
  Talking to your reflection in the mirror isn't going to help you mature. You might try interacting with other people.
The dangers... by rew · 2017-01-10 20:47 · Score: 2, Insightful

> the close call highlights the dangers of asteroids.
One: Nothing happened. So how dangerous was this? If it HAD hit, maybe several hundred people would've visited hospitals and some windows woudl have had to be replaced.
Two: The danger is teaching people "an asteroid killed the dinosaurs, what if an asteroid kills us?". That is dangerous. A really BIG asteroid killed the dinosaurs. These small ones are nothing to worry about. Let's assume this thing is aiming for earth, but hits randomly somewhere inside the moon's orbit. The earth has a radius of about 6000km, the moon's orbit about 300000km. A ratio of 50, so the chances of hitting earth are 1/2500. The people making a stir about these things are the ones that stand to gain employment from scaring the general public about this.
1. Re:The dangers... by Applehu+Akbar · 2017-01-10 23:04 · Score: 3, Insightful
  
  It was Chelyabinsk-sized. A direct hit on a city could kill millions of people.
2. Re:The dangers... by swb · 2017-01-11 00:00 · Score: 2
  
  Would the Chelyabinsk rock have caused millions of deaths had hit in exactly the same way, except with a major city as its epicenter?
  My non-rocket-scientist reading of the wikipedia page made it sound like it's shallow entry angle caused it to lose a lot of its energy in the atmosphere and that secondary effects (like broken windows from the airburst) was where most of the injuries came from. Although that kind of airburst over a place filled with glass curtain-wall skyscrapers may actually make it more dangerous in some ways.
  I guess we can be lucky that 70% of earth is covered by oceans, so conservatively even if a similar size rock hits again we've got a conservative 60% chance it happens over depopulated ocean.
3. Re:The dangers... by ledow · 2017-01-11 01:01 · Score: 3, Insightful
  
  You can't just divide the numbers. Gravity pulls stuff in, and the windows are tiny. Think Apollo 13 - only a tiny offset makes the difference between direct catastrophic entry and bouncing off the atmosphere.
  And we have NO WAY to change that trajectory anyhow.
  Also, statistically the chances are that most humans will die in such an impact - they're rare but when they happen they are INCREDIBLY serious. This was a BIG object, it would have changed life forever. It would have been "an event" not just a random meteorite landing on a desert or ocean.
  Also, the bit you're missing? We basically missed this. It's been circling the Sun forever, it's been going to hit us forever, and we didn't spot it. We probably don't have a way to effectively spot it and others like it.
  And a few thousands of a degree change in its arc and it would have been something that people recorded for the rest of future history and killed millions. It was only sheer chance that we "escaped".
  So, actually, as a mathematician and therefore of a scientific mind, this is a damn sight more important than what some orange fool said about some actress. By orders of magnitude.
  Roll on the day when THIS is the news and not all that other junk.
Re:Lucky by Opportunist · 2017-01-11 00:11 · Score: 2

False application of statistics. If statistics say that you'll have a flood every 30 years on average doesn't mean that because you had a flood this year it's impossible that there will be one next year. The chance for a flood is 1/30 every year. No matter how many floods you had in the past years.
Same for asteroid hits. One missing today doesn't increase the chance of one hitting tomorrow.

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Re:a space rock with an orbital distance from the by Deadstick · 2017-01-11 02:00 · Score: 3, Informative

A common measure of the "size" of an orbit is the semimajor axis -- which is half the length of the ellipse. You can have an orbit with a semimajor axis intermediate between those of Earth and Venus that can intersect both of them at various times, if its eccentricity is big enough.
Every gravitational interaction between two bodies alters both their orbits, to a degree that depends on their relative masses and on how close the approach is. This one's orbit will almost certainly change significantly -- hell, even Earth's orbit will change, but by an amount too small to observe.
Re:Minor damage by Anonymous Coward · 2017-01-11 02:26 · Score: 2, Informative

Yeah, but their target/placement isn't. Look for the missing islands in the atoll where they tested the really big bombs.
The moon is far by Nukenbar · 2017-01-11 03:01 · Score: 3, Informative

remember this is the real scale of the Earth to the moon.
http://colchrishadfield.tumblr.com/image/57696912776
Re:Minor damage by quenda · 2017-01-11 04:15 · Score: 2

Pedantic note: The bomb dropped on Hiroshima wasn't "nuclear", it was "atomic".

They are all "nuclear". Fission splits the nucleus in two.
> uses nuclear fusion to achieve most of its yield.
Not necessarily. In a big bomb, most of the yield can actually come from fission of the U238 tamper in the secondary.
The "Tsara Bomba" was only 50MT instead of 100 because the replaced the U238 damper with lead.
> "Atomic" bombs are fission-only devices
No, not always. They can be fusion-boosted single-stage weapons.
You're not real great at this "being pedantic" lark eh? :-)