M18 Observation Details
M18 Daily Motion
M18 will rise at 13:44, reaching 35° when twilight begins at 18:37. It will reach transit at 36° by 18:49 and will set before twilight ends at 23:54.M18 will be visible until October, 20, when it will move too close to the Sun. During this time, its proximity to the Sun will cause it to disappear from the night sky, making it unobservable for a while.
M18 Visibility Timetable on August 31
M18 Rise and Set Timetable
| Time | Elevation | |
| Moon Rise, 46.4% illuminated | 11:58 | -20° |
| M18 rise | 13:44 | |
| Sunset | 17:37 | 33° |
| Civil sunset | 18:05 | 35° |
| M18 transit | 18:49 | 36° |
| Astrosession begin | 19:10 | 35° |
| Moon Set | 21:19 | 25° |
| M18 set | 23:54 | |
| Astrosession end | 03:06 | -38° |
Track M18 Position Throughout the Night
← Sun, 31 August 2025 →
| Time | |
| Altitude | |
| Azimuth |
Where is M18 right now?
M18 is located in the constellation Sagittarius, at right ascension 18h 19m 58s" and declination -17° 06' 07s. Although it is currently above the horizon at an altitude of 10 degrees, M18 is not visible because it is daytime.M18 - Open Cluster
M18 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.
M18 spans about 8 light-years across and contains around 20 stars. The cluster is approximately 4,900 light-years away from Earth and has an apparent magnitude of 7.5, making it visible with binoculars or a small telescope.
M18 Image Gallery
DSS Blue
DSS Red
DSS Near-Infrared
DSS Composite image
The photos are taken from the Digitized Sky Survey 2 (DSS2), which was produced at the Space Telescope Science Institute (STScI) under NASA contract, using data from the UK Science and Technology Facilities Council (STFC), the European Southern Observatory (ESO), and the National Geographic Society-Palomar Observatory Sky Survey (POSS II).
Special thanks to the National Optical Astronomy Observatory (NOAO), the Royal Observatory, Edinburgh, and the California Institute of Technology for their significant contributions.
Finder Chart for M18
| Object name | M18 |
| Field of view | |
| Limiting magnitude | |
| M18 coordinates | 18.33291, -17.10197 |
| Center coordinates | 18.33291, -17.10197 |
M18 Passage Through Night
Current position of M18
| Time | 14:42 |
| Latitude | 37.3541 |
| Longitude | -121.955 |
| M18 elevation | 10° |
| M18 Azimuth | -121° |
Annual motion of M18
| Date | Sun, 31 August 2025 |
| Twighlight start | 19:06 |
| Twighlight end | 02:59 |
| Twighlight duration | 8h 54m |
| Rise | 13:40 |
| Set | 23:50 |
| Elevation at transit | 36° |
| Transit time | 18:45 |
| Equatorial coordinates | RA: 18h 19m 58s", Dec: -17° 06' 07s |
| Magnitude | 7 |
| Constellation | Sagittarius |
The graph is structured with the vertical axis showing the hours of the day, ranging from 12 AM to 12 AM the next day, while the horizontal axis spans each day of the year.
The reddish shaded area indicates the periods when the M18 is above the horizon, visible to observers. The white line marks the times when the celestial object reaches its highest point in the sky each day, known as the transit.
Astrometric & Physical Parameters of M18
Coordinates & Visibility
| Right Ascension | 18.33291° |
| Declination | -17.10197° |
| Magnitude | 6.90 |
| Constellation | Sagittarius |
| Elevation | 10.3° |
| Azimuth | -120.9° |
Data Credits
The nebulae information on this page is sourced from the OpenNGC project, developed by Matteo Verga. OpenNGC provides detailed data on the NGC catalog, which is a valuable resource for exploring deep-sky objects such as nebulae.
For more details or to contribute to OpenNGC, visit the official GitHub repository: OpenNGC on GitHub.