Less than 3 weeks ago, while America was getting the kids to school and arriving at work, an asteroid the size of a building slipped past Earth from a distance about halfway to the moon.
Now a similar space rock is about to zoom by our helpless planet.
The new near-Earth object (NEO), dubbed asteroid 2017 BX, was only discovered a few days ago, on Friday, January 20. It's slated to swing by Tuesday night at 11:54 p.m. ET at a distance of about 162,000 miles (261,000 kilometers) — roughly two-thirds the way to the moon.
We first heard about it via an email from Slooh, a company that airs live views of space, and they're hosting a broadcast about 2017 BX — which they've nicknamed "Rerun" — starting at 5:30 p.m. ET on Tuesday.
Asteroid 2017 BX, according to Slooh and data from NASA JPL, is similar to asteroid 2017 AG13, which flew by Earth on Monday, January 9. But this new asteroid is much smaller, at roughly 13 to 46 feet (4 to 14 meters) across — between the size of a car and a bus — and is moving at half the speed, approximately 16,600 miles (26,700 kilometers) per hour.
This is too small and too slow-moving of a rogue space rock to pose any real harm to Earth.
If its path had targeted our planet, and if it had been a loose pile of rocks (as most asteroids are) and not a metallic asteroid, it would break apart and burn up thousands of feet in the air, according to an asteroid-impact simulator called "Impact Earth!" by Purdue University.
However, the last-minute detection of 2017 BX is just another example of how blind we are to the millions of NEOs that could smack into our planet and release many atomic bombs' worth of energy.
NASA recently had the opportunity to fund a space telescope called NEOCam that'd help find 90% of NEOs of a size that's hard to detect yet could pose serious threats to human civilization. However, it balked for reasons that have yet to be made public, choosing two other missions (and ones to asteroids, no less).
Depending on where you live, pause for a moment tonight — Tuesday, January 24 at 11:54 p.m. ET — and imagine a rock the size of a truck flying overhead at 4.6 miles (7.4 kilometers) per second.
Then imagine 300,000 much-larger rocks out there that are big enough and moving fast enough to wipe out a major city.
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