the cup · pronounced KRAY-ter. Crater is a faint constellation representing a cup set on the long body of Hydra. Ptolemy catalogued it in the second century, and later Greco-Roman illustrations connected it with Apollo’s cup and the neighboring crow Corvus. No Crater star is brighter than fourth magnitude, so the outline requires a dark sky and is best approached from brighter landmarks in Leo, Virgo and Hydra. Its compact bowl-like polygon is highest on Northern Hemisphere spring evenings and remains accessible from much of the Southern Hemisphere. The constellation looks quiet through binoculars because it lies away from the Milky Way, but that clear extragalactic sightline reveals many remote galaxies. NGC 3511 and NGC 3513 form an attractive contrasting pair, while the unusual quasar RX J1131−1231 is famous for gravitational lensing by a foreground galaxy. Crater’s official IAU boundary defines the astronomical region; the classical cup is only one historical interpretation of selected stars. Cultural systems elsewhere partitioned this equatorial sky differently and should be cross-referenced without being treated as duplicates.
About Crater
Crater is one of the 88 constellations recognized by the International Astronomical Union. Its standard three-letter abbreviation is Crt, and astronomers use the genitive form Crateris when naming stars associated with it. The constellation's reference position lies around right ascension 11.7 hours and declination -15 degrees.
Its location places it in the celestial equator. For a typical mid-latitude observer, this part of the celestial sphere is especially well placed during spring evenings. Exact visibility depends on latitude, local horizon, date and time.
History and mythology of Crater
Historical origin
No Crater star is brighter than fourth magnitude, so the outline requires a dark sky and is best approached from brighter landmarks in Leo, Virgo and Hydra. Its compact bowl-like polygon is highest on Northern Hemisphere spring evenings and remains accessible from much of the Southern Hemisphere.
The modern constellation
Crater became one of the 88 official constellations standardized by the International Astronomical Union. Its boundary is a coordinate-defined sky region, while the familiar line figure joins only selected stars and has no physical depth.
Reading the cultural record
Names and stories attached to this part of the sky changed across languages, periods and communities. Cultural parallels should be identified from specialist sources rather than presented as interchangeable versions of Crater.
How to find Crater
- Use a location-aware chart and observe when Crater reaches its highest evening altitude; check that the full constellation rises from your latitude.
- Locate Delta Crateris, magnitude 3.6, then compare its direction with a brighter neighboring constellation rather than relying on line art alone.
- Trace the main pattern toward Alkes; binoculars reveal the fainter connecting stars while preserving a wide field.
- Move to NGC 3511 with a low-power eyepiece or binoculars, then increase magnification only if its surface brightness permits.
Bright stars in Crater
Delta Crateris
Notable star- Magnitude
- 3.6
- Distance
- 163 ly
An orange giant and the constellation’s brightest star, on the cup’s upper rim.
Alkes
Notable star- Magnitude
- 4.1
- Distance
- 174 ly
An orange giant whose traditional Arabic-derived name refers to the cup.
Gamma Crateris
Notable star- Magnitude
- 4.1
- Distance
- 84 ly
A white binary star marking another corner of the bowl.
Deep-sky objects in Crater
NGC 3511
A highly inclined spiral that shares a low-power field with smaller NGC 3513.
NGC 3513
A compact barred galaxy showing active star formation, near NGC 3511.
RX J1131−1231
A distant quasar split into multiple images by the gravity of an intervening galaxy.
Interesting facts about Crater
- Crater’s traditional name refers to cup, while its official IAU boundary defines a precise region of the sky.
- Delta Crateris, at magnitude 3.6, is a key star in Crater. An orange giant and the constellation’s brightest star, on the cup’s upper rim.
- NGC 3511 is a notable spiral galaxy in Crater. A highly inclined spiral that shares a low-power field with smaller NGC 3513.
- NGC 3513, a barred spiral galaxy, is another observing target within the constellation.
- No Crater star is brighter than fourth magnitude, so the outline requires a dark sky and is best approached from brighter landmarks in Leo, Virgo and Hydra.