Two Asteroid Day

By coincidence, two asteroids will come quite close to Earth today. They will pass by a bit closer than the Moon is to us, but not close enough to threaten our planet.

The first, 2010 RX30, passed by us this morning around 2:51am PDT.  It was about 151,100 miles from Earth (the Moon is on average 238,857 miles from us). RX30 is the bigger of the two we’ll see today, but still fairly small as asteroids go—it’s only about 32 to 65 feet across.

The second, 2010 RF12, is estimated at 20 to 46 feet in size and will pass by around 2:12pm PDT today at a distance of 49,088 miles.

Due to their small size, both were only recently discovered on Sunday morning during a routine monitoring of the skies as part of the Catalina Sky Survey near Tucson, Arizona. They orbit the sun in different patterns, so it is purely a “cosmic coinicidence” [SpaceWeather.com] that we’re seeing them both on the same day.

Perhaps most importantly, according to Universe Today,

Although the bodies were just discovered this week, their orbits have already been well established for the near future and neither will collide with Earth.

Dwayne Brown at NASA confirms we will be safe:

Neither of these objects has a chance of hitting Earth. A 10-meter-sized [32 feet] near-Earth asteroid from the undiscovered population of about 50 million would be expected to pass almost daily within a lunar distance, and one might strike Earth's atmosphere about every 10 years on average.

Even if they do, there’s no need to worry, says Universe Today:

The majority of the mass for such small objects would burn up in the atmosphere with only small fragments surviving to the ground.