M21 Position and Visibility Tonight

Where is M21 right now?

M21 is located in the constellation Sagittarius. It is currently above the horizon at an altitude of 5° toward the south-west, with an apparent magnitude of 5.90.

Open the interactive guide to M21’s position and path tonight

M21 tonight

M21 visibility on 2026-10-23

M21 Visible from sunset until before midnight

M21 rise and set timetable

	Time	Elevation
Moonrise, 80.5% illuminated	14:26	29°
M21 transit	15:06	30°
Sunset	16:20	28°
Civil sunset	16:47	26°
Twilight start (−12°)	17:18	23°
Astronomical observing session begins	17:48	19°
M21 set	19:51
Moonset	02:40	-74°
Astronomical observing session ends	03:56	-71°
M21 rise	10:16

Track M21 position throughout the night

← 23 October 2026 →

Time
Altitude
Azimuth

Shift the map to change the time and observe M21 changing position in the night sky.

M21 - Open Cluster

M21 is an open cluster located in the constellation Sagittarius. It was discovered by Charles Messier in 1764. The cluster contains a mix of young, hot stars and older stars.

M21 spans about 15 light-years across and contains around 57 stars. The cluster is approximately 4,250 light-years away from Earth and has an apparent magnitude of 6.5, making it visible with binoculars or a small telescope.

M21 — Image Gallery

DSS Blue

Blue images highlight younger, hotter stars that emit strongly at blue wavelengths.

DSS Red

Red images reveal older, cooler stars and emission nebulae glowing strongly in hydrogen-alpha light.

DSS Near-Infrared

Near-infrared images penetrate dust that obscures visible light and reveal hidden structures.

DSS Composite Image

DSS color images combine blue, red and often near-infrared exposures into a composite view.

The images come from the Digitized Sky Survey 2 (DSS2), produced at the Space Telescope Science Institute (STScI) under contract with NASA, using data from UK Science and Technology Facilities Council (STFC), European Southern Observatory (ESO), National Geographic Society-Palomar Observatory Sky Survey (POSS II).

Special thanks to National Optical Astronomy Observatory (NOAO), Royal Observatory, Edinburgh, California Institute of Technology for their significant contributions.

M21 Passage Through Night

Double-click to unlock the map.

Current position of M21

Time	19:24
Latitude	37.3541
Longitude	-121.955
Elevation	5°
Azimuth	237°

Here you can see the current position of M21 on the map, as well as its positions for rise and set. This tool lets you track its movement throughout the night with accurate, up-to-date information.

When Is M21 Visible Throughout the Year?

M21 will become visible again around April 8 after moving far enough from the Sun.

Date	Sat, 24 October 2026
Astronomical observing session begins	17:46
Astronomical observing session ends	03:54
Astronomical observing duration	10h 8m
Rise	10:16
Set	19:47
Elevation at transit	30°
Transit time	15:02
Equatorial coordinates	RA: 18h 04m 13s", Dec: -22° 29' 24s
Magnitude	6
Constellation	Sagittarius

The graph illustrates the annual visibility pattern of M21, including its daily appearances and transit times. The vertical axis shows the hours of the day and the horizontal axis spans the year. The reddish area marks when the object is above the horizon, while the white line marks its daily transit.
You can also see when M21 is visible throughout the year in a table with exact rise, transit, and set times for each date.

Astrometric and Physical Parameters of M21

Coordinates and Visibility

Right Ascension	18h 04m 13s
Declination	-22° 29′ 24″
Magnitude	5.9
Constellation	Sagittarius
Elevation	4.7°
Azimuth	236.9°

Data Credits

The deep-sky information on this page comes from the OpenNGC project developed by Matteo Verga. OpenNGC provides detailed catalog data for nebulae, galaxies, clusters and other deep-sky objects.

For details or contributions, visit the official repository: OpenNGC GitHub.

Observation Settings