Ptolemy's Cluster (M7) Position and Visibility Tonight
Where is M7 right now?
Twilight begins at 18:26 local time. At that moment, M7 will be 18° above the horizon toward the south.
M7 visibility on 2026-09-07
M7 rise and set timetable
| Time | Elevation | |
| M7 rise | 14:05 | |
| Moonset | 14:56 | 7° |
| Sunset | 17:27 | 18° |
| Civil sunset | 17:55 | 18° |
| M7 transit | 17:56 | 18° |
| Twilight start | 18:26 | 18° |
| Astronomical observing session begins | 18:58 | 16° |
| M7 set | 21:48 | |
Moonrise, 21% illuminated  | 23:21 | -14° |
| Astronomical observing session ends | 03:13 | -57° |
Track M7 Position Throughout the Night
← 7 September 2026 →
| Time | |
| Altitude | |
| Azimuth |
M7 - Ptolemy's Cluster
Ptolemy's Cluster (M7) is an open cluster located in the constellation Scorpius. It was known to ancient astronomers and included in Messier's catalog in 1764. The cluster is named after the Greek-Roman astronomer Claudius Ptolemy, who mentioned it in his writings around 130 AD.
M7 spans about 25 light-years across and contains around 100 stars. The cluster is approximately 980 light-years away from Earth and has an apparent magnitude of 3.3, making it visible to the naked eye and easily seen with binoculars or a small telescope.
M7 — Image Gallery
DSS Blue
DSS Red
DSS Near-Infrared
DSS Composite Image
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.
Finder Chart for M7
| Object name | M7 |
| Field of view | |
| Limiting magnitude | |
| M7 coordinates | 17.89755, -34.79283 |
| Center coordinates | 17.89755, -34.79283 |
Ptolemy's Cluster (M7) Passage Through Night
Current position of Ptolemy's Cluster (M7)
| Time | 13:29 |
| Latitude | 37.3541 |
| Longitude | -121.955 |
| Elevation | -5° |
| Azimuth | 131° |
When Is Ptolemy's Cluster (M7) Visible Throughout the Year?
M7 will remain visible until November 19, when it moves too close to the Sun and temporarily disappears from the night sky.
| Date | Mon, 7 September 2026 |
| Twilight start | 18:54 |
| Twilight end | 03:07 |
| Twilight duration | 8h 13m |
| Rise | 14:01 |
| Set | 21:44 |
| Elevation at transit | 18° |
| Transit time | 17:52 |
| Equatorial coordinates | RA: 17h 53m 51s", Dec: -34° 47' 34s |
| Magnitude | 3 |
| Constellation | Scorpius |
You can also see when M7 is visible throughout the year in a table with exact rise, transit, and set times for each date.
Astrometric and Physical Parameters of M7
Coordinates and Visibility
| Right Ascension | 17h 53m 51s |
| Declination | -34° 47′ 34″ |
| Magnitude | 3.30 |
| Constellation | Scorpius |
| Elevation | -5.3° |
| Azimuth | 130.5° |
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.