HCG 1 is a compact group of galaxy in the Hickson Compact Group catalogue identified using a systematic search by the Palomar Observatory Sky Survey led by Paul Hickson in 1982. This group is composed of four interacting member galaxies, two of which are peculiar.
Properties A study proves that HCG 1A is the brightest in this group, having an absolute magnitude of 20.6, Corrected Total Blue Magnitude (B_TC) of 14.43 and Blue minus Red (B-R) 1.29, indicating this galaxy is undergoing vigorous star birth and formation. HCG 1B, 1C and 1D have absolute magnitudes of 20.0, 19.5 and 18.5, suggesting that HCG 1D is in a high chance of being dominated by old, cool and ageing stars. Hickson Compact Group 1 has a Crossing Time () of 0.0479 and a Radial Velocity Dispersion (km/s) of 85.1. This proves that HCG 1 is a stable and moderate evolving group and this group has an environment that is conducive to have frequent gravitational interactions, which affect galaxies morphological shape and may increase star formation in certain interaction areas.
A study shows that HCG 1 have a total of 13 foreground stars, 9 foreground unidentified objects and 10 foreground galaxies. Hickson Compact Group 1 has a total of 2 out of 4 galaxies that are spirals, the spiral fraction is exactly 5 or 0.5.
Another study shows that HCG 1A and 1B has a tidal arm, indicating that they are gravitationally interacting within themselves or with other galaxies.
Members Hickson Compact Group 1 have 4 members. Their details and information are stated in the table below. +Members of HCG 1HGCNameTypeMag.Right AscensionDeclinationDistanceMajor Axis DiameterMinor Axis DiameterB_TCB−RRedshiftVelocity (km/s)1aPGC 1627Sbc? peculiar15.000 26 07.1 +25 43 31460 Mly37.6026.9014.431.290.034147 102371bPGC 1625S0/a? peculiar15.500 26 06.0 +25 43 09460 Mly42.8010.7015.041.360.034227 102661cPGC 1614E115.900 25 54.4 +25 43 25450 Mly10.7010.7015.571.690.033543 100561dPGC 1618S017.400 25 58.8 +25 43 31455 Mly8.504.8016.501.600.033757 10120
References