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Am I the only one who read the article hoping for a "If it DID hit the earth, X would happen..."?
The Moon is much larger and much farther away from the Earth than you are probably imagining when you hear this. Still cool, though.
http://eoimages.gsfc.nasa.gov/images/imagerecords/51000/5196...
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.
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…
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.
Earlier quoted context omitted.
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.
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?
EDIT: in case you couldn't fathom, that was sarcasm.
EDIT 2: seriously, stop it! or reply as to why are you down voting? is it a crime to mistakenly post a comment and then acknowledge your mistake or are you guys just some proud 'elite' HNers?
The Moon is much larger and much farther away from the Earth than you are probably imagining when you hear this. Still cool, though.
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?
The moon has a mass of 7.349×10²² kg. Its mean orbital velocity is 1023m/s. So, with a perfectly-aligned impact, and perfect efficiency, to add velocity, you'd need to add energy equal to difference in kinetic energy. For 1m/s, that'd be 10²⁵J (assuming the change in mass is negligible). That's an incredible amount of energy, about 20 times greater than the Chicxulub impact (believed to have triggered the mass extinctions at the K-T boundary).
That's 1 m/s. You need far more than that. Earth escape velocity is 11200m/s. So, that would seem to need 10³⁰ J. And an impact would deliver that in well under a minute. Which would be a problem, since that's an order of magnitude greater than the gravitational binding energy of the moon.
Conclusion: impact required would fully obliterate moon.
(Moon mass and velocity, and escape velocity from http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html. Gravitational binding energy and estimate of Chicxulub from Wolfram Alpha)
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?
Good question - an aircraft carrier nearer than the moon? I can't imagine that'd be visible to the naked eye - even ships on the horizon disappear pretty quick. Then again you can see satellites sometimes, but that's like 4 orders of magnitude closer.
Would be interesting if during the flyby our analysis revealed that it was made up of a Gold core or something :). Suddenly NASA might get a bunch of funding to prepare for the next flyby
Wouldn't flooding the market with that much gold...crash it? Are we really talking about that many billions and billions of dollars worth of potential revenue from mining an asteroid?
This all just seems like fun sci-fantasy.
