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Asteroid set to come closer to the Earth than the moon Nov. 8

nasa.gov

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Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#11

Post by Achshar »

ibrow wrote: post #9
Achshar wrote: post #4

Earlier quoted context omitted.

from NASA's gif, it doesn't even bend its trajectory.. and also it's gravity will not affect earth's tides and tectonic plates :) EDIT: although from the gif it appears that it was a close call on the moon. But i close my eyes and i see a world where i get out and see a small piece of rock hit our moon with a decent explosion when the moon is full. Man if it does't affect out planet in any way, i would really like to…

There's a thought. What would happen, hypothetically speaking, if an asteroid large enough were to hit the moon and spin it out of its orbit? What would happen to life here on Earth? Obviously tides would be affected, and I am assuming that this in itself would probably affect a lot of animals, fish, birds etc?

well moon moving out of its trajectory means alot more than tides (which in itself is pretty darn serious) IMO. The nights would be absolutely dark, also earth's rotation speed (AFAIK) is also affected by moon's gravity and bulges in both earth and moon's softer crust. Plus maybe we can adapt to such changes but our culture will change and it will be alot more difficult to live through that, imagine explaining to your kids/grandchildren what moon is (or rather was) and how it looked when it was closer/farther.

PS if moon gets a major hit, its highly unlikely earth stays 'physically' unaffected. The aftermath of the collision would leave numerous chunks of huge rocks in earth's near space and it would be almost certain that some of then then hit earth. And the effect of decent sized rock hitting the planet is better known to our long lost friends, the dinosaurs :)

Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#15

Post by nitrogen »

ibrow wrote: post #9
Achshar wrote: post #4

Earlier quoted context omitted.

from NASA's gif, it doesn't even bend its trajectory.. and also it's gravity will not affect earth's tides and tectonic plates :) EDIT: although from the gif it appears that it was a close call on the moon. But i close my eyes and i see a world where i get out and see a small piece of rock hit our moon with a decent explosion when the moon is full. Man if it does't affect out planet in any way, i would really like to…

There's a thought. What would happen, hypothetically speaking, if an asteroid large enough were to hit the moon and spin it out of its orbit? What would happen to life here on Earth? Obviously tides would be affected, and I am assuming that this in itself would probably affect a lot of animals, fish, birds etc?

An asteroid that could move the moon would have to be moving insanely fast, or be close to the size of the moon (due to conservation of momentum).

Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#16

Post by mturmon »

Cushman wrote: post #8
adyus wrote: post #3

Let's hope it has enough velocity to escape Earth's field and carry on. I'm sure it does, but I'll keep my fingers crossed, just in case.

Give science a little more credit :) The n-body problem is hard, but it's more like "we don't know if this same asteroid will hit the Earth 20 years from now" hard than "this asteroid could shift course at any moment!" hard.

From an earlier press release on this asteroid, from a 2010 pass:

[The radar imaging] reveals 2005 YU55 as a spherical object about 400 meters (1,300 feet) in size.

Not only can the radar provide data on an asteroid's dimensions, but also on its exact location in space. Using Arecibo's high-precision radar astrometry capability, scientists were able to reduce orbit uncertainties for YU55 by 50 percent.

"At one time we had classified 2005 YU55 as a potential threat," said Steve Chesley, a scientist at JPL's Near-Earth Object Program Office. "Prior to the Arecibo radar passes on April 19 thru 21 [2010], we had eliminated almost all upcoming Earth flybys as possibilities of impact. But there were a few that had a low remaining probability of impact. After incorporating the data from Arecibo, we were able to rule impacts out entirely for the next 100 years."

*

So, they do know this one will be well-behaved for 100 years.

Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#17

Post by brlewis »

Achshar wrote: post #2

Brace yourselves: the doomsday articles/memes/stories are coming.. PS will it be visible to naked eye? if yes then when and where and for how long and where in the sky? can there be a real time Google earth 3d simulation like NASA did for space shuttle launch?

The asteroid's surface is darker than charcoal at optical wavelengths. Amateur astronomers who want to get a glimpse at YU55 will need a telescope with an aperture of 6 inches (15 centimeters) or larger.

Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#18

Post by hugh3 »

Cushman wrote: post #8
adyus wrote: post #3

Let's hope it has enough velocity to escape Earth's field and carry on. I'm sure it does, but I'll keep my fingers crossed, just in case.

Give science a little more credit :) The n-body problem is hard, but it's more like "we don't know if this same asteroid will hit the Earth 20 years from now" hard than "this asteroid could shift course at any moment!" hard.

The n-body problem is hard to solve analytically, but trivially easy to solve to arbitrarily high precision numerically.

Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#19

Post by ibrow »

Achshar wrote: post #11
ibrow wrote: post #9

Earlier quoted context omitted.

There's a thought. What would happen, hypothetically speaking, if an asteroid large enough were to hit the moon and spin it out of its orbit? What would happen to life here on Earth? Obviously tides would be affected, and I am assuming that this in itself would probably affect a lot of animals, fish, birds etc?

well moon moving out of its trajectory means alot more than tides (which in itself is pretty darn serious) IMO. The nights would be absolutely dark, also earth's rotation speed (AFAIK) is also affected by moon's gravity and bulges in both earth and moon's softer crust. Plus maybe we can adapt to such changes but our culture will change and it will be alot more difficult to live through that, imagine explaining to you…

Thanks for that. Quite a thought. Hopefully this will never happen - am assuming that the Earth has more chance of being hit than the moon (the moon being smaller and faster)?

But would the nights be totally dark? I've experienced a lot of nights out on a boat on a moonless night and the stars provide a (relatively) large amount of light on their own.

Re: Asteroid set to come closer to the Earth than the moon Nov. 8

#20

Post by hugh3 »

Achshar wrote: post #4
adyus wrote: post #3

Let's hope it has enough velocity to escape Earth's field and carry on. I'm sure it does, but I'll keep my fingers crossed, just in case.

from NASA's gif, it doesn't even bend its trajectory.. and also it's gravity will not affect earth's tides and tectonic plates :) EDIT: although from the gif it appears that it was a close call on the moon. But i close my eyes and i see a world where i get out and see a small piece of rock hit our moon with a decent explosion when the moon is full. Man if it does't affect out planet in any way, i would really like to…

Don't forget that's a two-dimensional picture of 3D space, so it's probably not nearly as close to the moon as it appears. While most of the objects in the solar system are in kinda-sorta the same plane, they're not quite.
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