Another moon for Earth

Astronomers have discovered an asteroid whose solar orbit is almost identical to Earth’s, and has it hovering so near the Earth that it is almost another moon.

Based on orbital data the scientists estimate that the asteroid, between 300 to 1000 feet in diameter, has been hovering near Earth for the past 775 years, and it will only drift away in about 165 years from now.

Correction: Engineer and regular reader James Fincannon emailed me to note that this asteroid really doesn’t have an orbit “almost identical to the Earth.” As he wrote, “Seems to go between Venus and Mercury and then all the way out to Mars! It seems to pass by Earth occasionally.” Thus, this recent period of closeness is only a temporary one.