An illustration of what asteroid 2012 DA 14 may look like as it approaches Earth.

The rock known as 2012 DA14 will fly past around 2:24 p.m. ET. It will be closer than many satellites and the size of an office building. And it will be nearer to the planet than anything else of its size that we know of.

NASA calls it a "small near-Earth asteroid."

And though "2012 DA14" will come within about 17,000 miles of our planet and be closer than some satellites, the space agency assures everyone that "there is no chance that the asteroid might be on a collision course with Earth."

Still, if what we read about this rock and our calculations are correct, the asteroid that comes whizzing by around 2:24 p.m. ET on Friday:

-- Will be traveling at 17,000 miles per hour.

-- Will be about 150 feet across. NPR's Nell Greenfieldboyce compares it to a small office building.

-- Will be about the same weight as 318 fully loaded Boeing 747s.

-- Will set a record for "close[st] approach for a known object of this size," according to NASA.

So, if somebody's miscalculated it's path ...

Let's just not go there.

Though, if you really want to calculate what an asteroid like that would do to the planet if it did hit, Purdue University has a handy "Impact Earth" calculator.

Oh, and sorry folks in the U.S. You won't be able to see it. (We hope.)

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