HCG 87 explained

HCG 87 is a compact group of galaxies listed in the Hickson Compact Group Catalogue. This group is about 400 million light-years away ^[1] in the constellation Capricornus. The group distinguishes itself as one of the most compact groups of galaxies, hosting two active galactic nuclei and a starburst among its three members, all of which show signs of interaction.^[2] This interaction, which astronomers have called visually, and scientifically, intriguing^[3] is being examined to understand the influence of active nuclei on star formation histories.

Members

Members of the HCG 87

Name	Type^[4]	R.A. (J2000)	Dec. (J2000)	Redshift (km/s)	Apparent Magnitude
HCG 87a	S0 pec			8443 ± 14	15.3
HCG 87b	SA(r)0 pec			8740 ± 20	15.4
HCG 87c	Sb			8914 ± 7	16.1
HCG 87d	Sd			10200 ± 160	17.8

External links

• Astronomy Picture of the Day
  • Galaxy Group HCG 87 – 2003 July 31
  • HCG 87: A Small Group of Galaxies – 2010 July 6
• Close-ups of HCG 87
• Galactic Clusters
• Studies of Hickson Compact Groups

Notes and References

1. Web site: This redshift corresponds to a distance of 120Mpc or 400 million light years (using H₀ = 75km/s/Mpc and q₀ = 0.1). At the distance of the group, this corresponds to a group diameter of 52kpc, i.e., the group is approximately 170,000 light years across . dead . 19 February 2020 . https://web.archive.org/web/20200219030953/http://heritage.stsci.edu/1999/31/hicktable.ps . PS File download need Photoshop or GIMP .
2. Noll, Keith. 07/1999. "Hubble Heritage observations of Hickson Compact Galaxy Group 87".
3. English, J. et al. 05/2000. "A Minuet of Galaxies: Hickson Compact Group 87 as Viewed by the Hubble Space Telescope". American Astronomical Society, 195th AAS Meeting, #136.04; Bulletin of the American Astronomical Society, Vol. 32, p.884.
4. Web site: NASA/IPAC Extragalactic Database . Results for various galaxies . 2006-10-19.