APOD: Messier 24: Sagittarius Star Cloud (2023 Jun 28)

[APOD Robot]

Messier 24: Sagittarius Star Cloud

Explanation: Unlike most entries in Charles Messier's famous catalog of deep sky objects, M24 is not a bright galaxy, star cluster, or nebula. It's a gap in nearby, obscuring interstellar dust clouds that allows a view of the distant stars in the Sagittarius spiral arm of our Milky Way galaxy. Direct your gaze through this gap with binoculars or small telescope and you are looking through a window over 300 light-years wide at stars some 10,000 light-years or more from Earth. Sometimes called the Small Sagittarius Star Cloud, M24's luminous stars fill this gorgeous starscape. Covering over 3 degrees or the width of 6 full moons in the constellation Sagittarius, the telescopic field of view includes dark markings B92 and B93 near center, along with other clouds of dust and glowing nebulae toward the center of the Milky Way.

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[Ann]

Messier 24: Sagittarius Star Cloud
Image Credit & Copyright: Emmanuel Astronomono

Messier 24, APOD 2018 June 29. Image Credit & Copyright: Roberto Colombari

The well-known astrophotographer Roberto Colombari had an APOD with his picture of Messier 24 (M24) on June 29, 2018. Colombari is an expert on RGB photography, which is something I love, of course. I find Roberto Colombari's APOD easier to "read" than today's APOD.

There is a great picture by BQ Octantis at Cloudy Nights that helps you put M24 into perspective:

Star clouds, clusters and notable stars in M24.
Credit: BQ Octantis at Cloudy Nights.

The Large Sagittarius Star Cloud is the brightest part of the Milky Way. There is an opening in the thick central dust lane here that allows us to see the bright yellow bulge of the Milky Way.

M24 is a much smaller star cloud. Note, however, its blue color. The color is due to the fact that there are many young stars in M24. By contrast, virtually all the hundreds of millions (or billions?) of stars in the Large Sagittarius are old and yellow.

Ann

[VictorBorun]

is there an IR view of M24 and Large Sgr with dust frames half-transparent?

showing how close they are to the disk and to the bulge of the Milky Way

[Christian G.]

Sometimes a little light pollution can almost be your friend (almost…), in this instance when I look at M24 from where I live it appears as a well-defined sparkling open cluster easy to make out and enjoy! Then an APOD like this comes along and I can fill in countless details...

[Cousin Ricky]

I’ve never seen M24 with this level of clarity before.

[Judith G]

What is the (apparent) string of stars at 11 o'clock in the Messier 24 photo of June 28, 2023?

[johnnydeep]

What is the (apparent) string of stars at 11 o'clock in the Messier 24 photo of June 28, 2023?

Do you mean this arc?

[Judith G]

Yes, and continuing to the left a bit

[johnnydeep]

Yes, and continuing to the left a bit

Then I think that apparent arc of stars is simply a result of random alignment along our particular line of sight. And it just so happens that humans' pattern recognition software is extremely adept at being able to pick out such alignments - and attempting to assign deeper meaning to such alignments - from all the other mostly random positions of stars in a star field.