Bob Moler's Ephemeris Blog

This is Ephemeris for Thursday, July 10th. Today the Sun will be up for 15 hours and 21 minutes, setting at 9:28, and it will rise tomorrow at 6:08. The Moon, at full today, will rise at 9:58 this evening.

In recent programs I’ve talked about an asteroid, 2024 YR4, that has a 4% chance of hitting the Moon in 2032, and the possibility that debris from the lunar impact would make it all the way back to the Earth and cause problems with our satellites. The asteroid is too far away now to for further observations, so that’s where the probability stands. The asteroid has a four-year orbit of the Sun so toward the latter part of the year 2028 it should again be in range for astronomers to observe and refine its orbit to see if the probability of striking the Moon increases or even decreases. According to a recent paper about the ejecta from the impact, there seems a better chance of earthward debris if the asteroid hits the trailing part of the Moon, that is its right side as we see it.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum