Collinder 140

Collinder 140 is a nearby open cluster of stars in the constellation Canis Major. It was first catalogued in 1751 by the French astronomer Nicolas Louis de Lacaille, who described it as a "nebulous star cluster". It was catalogued again by the Swedish astronomer Per Collinder in 1931.^[5] Fitzgerald et al. (1980) describe it as "a young extended cluster" and note that it is not obviously a cluster and may instead be a mere grouping of stars that formed together.^[4]

Observation data (J2000.0 epoch)
Right ascension	07h 24m 53s[1]
Declination	−31° 52′ 23″[1]
Distance	1,226 ly (376 pc)[2]
Apparent magnitude (V)	3.5[3]
Apparent dimensions (V)	60′[1]
Physical characteristics
Estimated age	20 million years[4]
Other designations	Cr 140
Associations
Constellation	Canis Major
See also: Open cluster, List of open clusters

Based on the combined parallax measurements of nine cluster members, this cluster has an estimated parallax of 2.66 ± 0.13 mas, which is equivalent to a distance modulus of 7.88 ± 0.11,^[2] or a distance of 1,226 light-years (376 pc). The cluster has a density of 0.21 solar masses per cubic parsec; roughly double the density of stars near the Sun. It is about 20 million years old,^[4] and may have been created from the same interstellar cloud that formed NGC 2516 and NGC 2547.^[6]