01/24/2023 – Ephemeris – The “green” comet’s designation is C/2022 E3 (ZTF)

This is Bob Moler with Ephemeris for Tuesday, January 24th. Today the Sun will be up for 9 hours and 29 minutes, setting at 5:40, and it will rise tomorrow at 8:09. The Moon, 3 days past new, will set at 9:26 this evening.

Yesterday, I began covering new comet that’s in our skies. I didn’t mention its name. It’s got an odd one. Its designation is C/2022 E3, which means it was discovered in 2022. E means that it was in the 5th half month of the year, which puts it in early March, and three is the third object in that period. The name that goes along with it is actually the initials ZTF which stand for Zwicky Transient Facility which is actually 2 observatory complexes, one in California and the other one in Chile which looks for things that go bump in the night. Basically, things that change their brightness or movement in the short period of time. They cover the whole sky eventually and get back and see what’s changed. The facility is named after astronomer Fritz Zwicky.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.

Addendum

The track of Comet ZTF from tonight at 9 pm to January 30, 2023. Two constellations are named. The unnamed constellation line running through the image is the tail of Draco the dragon. The red dots are galaxies, much dimmer than the comet. The depiction of the comet’s tail simply suggests the direction of the tail. Comet positions are set for 9 pm on the dates shown. For each position, the date and magnitude are shown as in “mm-dd mag”, the year is omitted. Magnitudes are very subjective.