Asteroids are raining down on us all the time, most burn up in our atmosphere from the friction they encounter with the molecules of air.  Witness the moons millions of pockmarks because with no atmosphere anything headed to the moon crashes into it.

Most of the free floating minutia in space is pretty small but now and then a sizable asteroid is spotted and sometimes they come near earth.

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Tomorrow an asteroid the size of the Rock of Gibraltar will pass at a 'safe but uncomfortably close distance' according to astronomers.  If you're measuring, the asteroid named 2014-J25 will come within 1.1 million miles of hitting us, that's a distance that's only about five times further out than the moon.

Once it whizzes past us - on it's return leg from a loop around the sun it'll speed on out toward Jupiter before it u-turns and comes back, passing us again around 2600.  The last time J25 was in the neighborhood was about 400 years ago when the British Navy dominated the seas and the United States had hardly even been colonized.

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No asteroid post would be complete without a photo of Bruce Willis,

so here ya go. He has nothing else to do with the post.

Astronomers note that as J25 passes and for a couple of days, it will be visible from Earth with most ordinary telescopes - so go out in the backyard and see if you can spot it over the next couple of nights.

And if you've got your calendar handy, make a note that the next close asteroid fly-by will be 199-AN10 which is a mere half-mile wide rock and it'll come by in about ten years at just 236,000 miles!  Hold onto your hats for that one.