Cancer Constellation
Cancer (The Crab)
Cancer is one of the 13 ecliptic constellations and represents a crab in Greek mythology. Though it is relatively faint and lacks bright stars, Cancer is rich in history and mythological significance. It is best known for the famous Beehive Cluster located within its boundaries.
Key Features
- Bright Stars: Cancer does not have exceptionally bright stars, but it includes:
- Beta Cancri (Tarf): The brightest star in Cancer, an orange giant located approximately 290 light-years away.
- Delta Cancri (Asellus Australis): A yellow giant star marking part of the crab’s body, also notable for its proximity to the Beehive Cluster.
- Gamma Cancri (Asellus Borealis): A white star representing the northern part of the crab’s body.
- Deep-Sky Objects: Cancer is home to one of the most famous star clusters:
- Beehive Cluster (Messier M44): A bright open star cluster visible to the naked eye, often described as a "swarm of bees."
- Messier 67 (M67): An older and more compact open cluster, containing thousands of stars and considered one of the most studied star clusters.
Mythological Background
In Greek mythology, Cancer is associated with the crab sent by Hera to distract Heracles during his battle with the Hydra. Despite being crushed by Heracles, the crab was honored by Hera and placed among the stars. Cancer’s story reflects themes of perseverance and loyalty, even in the face of overwhelming odds.
The crab also appears in Babylonian mythology, where it was linked to the Moon and water, symbolizing life, fertility, and renewal.
Cultural Significance
Cancer has been historically significant in marking the summer solstice in ancient times. The Tropic of Cancer, a line of latitude, derives its name from the constellation because the Sun once appeared in Cancer during the solstice. Although precession has shifted this alignment, the name persists as a reminder of Cancer’s role in early astronomy.
Cancer Rise and Set Timetable
| Time | Elevation | |
| Cancer transit | 09:04 | 70° |
| Cancer set | 15:57 | |
Moonrise, 100% illuminated  | 17:35 | -17° |
| Astronomical observing session begins | 18:42 | -26° |
| Cancer rise | 02:07 | |
| Astronomical observing session ends | 03:36 | 17° |
| Civil sunrise | 04:08 | 23° |
| Sunrise | 04:36 | 29° |
| Moonset | 05:04 | 35° |
Track Cancer Position Throughout the Night
← 28 August 2026 →
| Time | |
| Altitude | |
| Azimuth |
Nebulae in the constellation Cancer
M44
Open Cluster
M67
Open Cluster
NGC2744 NED01
Galaxy
Annual motion of Cancer
| Date | Fri, 28 August 2026 |
| Twilight start | 19:11 |
| Twilight end | 02:56 |
| Twilight duration | 8h 45m |
| Rise | 02:07 |
| Set | 15:53 |
| Elevation at transit | 70° |
| Transit time | 09:00 |
| Equatorial coordinates | RA: 08h 20m 10s", Dec: 17° 02' 10s |
| Magnitude | - |
| Constellation |
The vertical axis shows the hours of the day, while the horizontal axis spans the days of the year.
The reddish area marks when the constellation is above the horizon. The white line shows when it reaches its highest point in the sky. View detailed visibility information in a table with rise, transit, and set times for each date.
Acknowledgements
We gratefully acknowledge the International Astronomical Union (IAU) for defining and standardizing the official constellation boundaries used in celestial mapping.
Special thanks to Sky & Telescope Magazine and contributors Roger Sinnott and Rick Fienberg for producing the charts and tables. Alan MacRobert’s constellation patterns were influenced by the work of H. A. Rey and adjusted to align with earlier traditions.