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Ephemeris: 09/05/2024 – Looking at the center of the Milky Way

September 5, 2024 Comments off

This is Ephemeris for Thursday, September 5th. Today the Sun will be up for 13 hours even, setting at 8:11, and it will rise tomorrow at 7:11. The Moon, 3 days past new, will set at 9:09 this evening.

The moon sets in twilight so it will not bother viewing of the Milky Way when it gets dark. Looking to the south and little Teapot asterism of the constellation Sagittarius is the center of the Milky Way. It’s located just off the tip of the spout of that teapot. It’s about 25 to 27,000 light years away and is blocked from our view by clouds of gas and dust. In it lies the Milky Way’s central black hole. Astronomers have found that most galaxies have a black hole in their centers. Ours, it turns out, is a little smallish for our size of galaxy. It has the mass of four million times the mass of the Sun. Imaging of our black hole occurred at the same period of time that the data for the black hole in the galaxy M87. But its image took longer to produce due to the obstruction of that dust and gas.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT–4 hours). Times will be different for other locations.

Addendum

A visible light photograph of Sagittarius annotated with the Teapot asterism and pointer to the center of the Milky Way Galaxy behind that dark cloud.
The seeming chaos at the heart of our galaxy, seen here in three different wavelengths of electromagnetic radiation. Red is far infrared from the Spitzer Space Telescope. Yellow is from the near infrared from the Hubble Space Telescope. And blue is X-rays from the Chandra Space Telescope. Sagittarius A is the first radio source ever discovered beyond the Sun and marks the center of the Milky Way Galaxy. It contains the supermassive black hole Sagittarius A*. Click or tap on the image to enlarge it. Credit: NASA.
Milky Way Black Hole
This is the image released May 12, 2022 by the Event Horizon Telescope Collaboration of Sagittarius A*, the supermassive black hole at the center of our galaxy. Note that the asterisk (*) is pronounced “star”.