The Crater is the goblet of Apollo. Its shape
does resemble a drinking glass, slightly askew in the sky, which is
why other ancient cultures also saw this group of stars as some kind
of vessel. Its stars are generally fourth
Alpha Crateris is known as Alkes, Arabian for "shallow basin". The star marks the western corner of the stem, with beta Crateris marking the other corner.
Alkes is an orange (or yellow) giant, about 15 times the diameter of the Sun, and 110 light years away.
The brightest star in the constellation is delta Crateris, which
marks the bottom of the bowl. It's about seven times the size of our
Sun, and is 73 light years away.
Double stars in Crater:
Gamma Crateris is a fixed binary: 4.1, 9.6; PA 96º, separation
Iota Crateris is a close binary: 5.5, 11; PA 226º, separation
Psi Crateris is an even closer binary: 6.5, 7; PA 358º, separation 0.2".
Variable Stars in Crater:
None of the Bayer stars of Crater are considered to be variable. The
constellation has several semi-regular variables, the brightest of which
is R Crateris: 8.0-9.5 with a period of about 160 days.
Deep Sky Objects in Crater:
Crater has no Messier objects, and its reported deep sky objects are all
very faint galaxies.
For a closer appreciation of Crater, visit the Binocular Section.