Archive for December 12, 2022

12/12/2022 – Ephemeris – Orion and the scorpion

December 12, 2022 Comments off

This is Bob Moler with Ephemeris for Monday, December 12th. Today the Sun will be up for 8 hours and 51 minutes, setting at 5:02, and it will rise tomorrow at 8:11. The Moon, 4 days before last quarter, will rise at 9 this evening.

The wonderful constellation of Orion the hard luck hunter is seen rising in the east as twilight fades. According to one Greek myth he was killed by the sting of a scorpion, thus he can only rise as the summer constellation of Scorpius the scorpion sets in the southwest, and he must set as the scorpion rises on early spring evenings. By 9 pm, he is located in the east-southeast. His three belt stars are nearly vertically arranged in a line and equally spaced. They point down to the horizon, where the brightest nighttime star Sirius will rise at about 9:20 pm. The belt stars lie within a large rectangle of stars tilted to the left. His shoulders and knees. The top left star is the bright red Betelgeuse. The bottom right star is blue-white Rigel. We’ll explore more of Orion all winter.

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.


Graphic showing the positions of Orion and Scorpius as the hunter rises

A panorama showing Orion rising while Scorpius the scorpion is below the horizon. Both the atmosphere and the ground were removed in this view. The horizon is the green horizontal line. Orion, apparently, is so afraid of the scorpion, that he won’t enter the sky until the scorpion is long gone, putting the Sun between the two. This business of the two never being in the sky at the same time only works for observers in the Earth’s Northern Hemisphere. Click on the image to enlarge it. Created using Stellarium