NGC 3751
{{Short description|Galaxy in the Copeland Septet}}
{{Infobox galaxy|name=NGC 3751|image=File:NGC 3751.jpg|caption=NGC 3751|constellation name=Leo|ra=11h 37m 53.859s|dec=+21d 56m 11.34s|z=0.031328|h_radial_v=9,392 km/s|dist_ly=450 Mly (138 Mpc)|group_cluster=Copeland Septet|appmag_v=14.3|type=E4, E-S0|size=144,000 ly|names=PGC 36017, UGC 6601, MCG +04-28-009, 2MASX J11375386+2156110, SDSS J113753.85+215611.3, Copeland Septet NED05, HCG 057F, NSA 112845, SSTSL2 J113753.87+215611.2, LEDA 36017|epoch=J2000}}
NGC 3751 is a type E-S0{{Cite web |title=HyperLeda -object description |url=http://atlas.obs-hp.fr/hyperleda/ledacat.cgi?o=NGC%203751 |access-date=2024-05-03 |website=atlas.obs-hp.fr}} lenticular galaxy located in the Leo constellation.{{Cite web |last=Astronomy |first=Go |title=NGC 3751 {{!}} galaxy in Leo {{!}} NGC List {{!}} GO ASTRONOMY |url=https://www.go-astronomy.com/ngc.php?ID=3979 |access-date=2024-05-03 |website=Go-Astronomy.com |language=en-US}} It is located 450 million light-years away from the Solar System{{Cite web |title=Your NED Search Results |url=https://ned.ipac.caltech.edu/cgi-bin/objsearch?search_type=Obj_id&objid=56897&objname=6&img_stamp=YES&hconst=73.0&omegam=0.27&omegav=0.73&corr_z=1 |access-date=2024-05-03 |website=ned.ipac.caltech.edu}} and was discovered by Ralph Copeland on April 5, 1874.{{Cite web |title=New General Catalog Objects: NGC 3750 - 3799 |url=https://cseligman.com/text/atlas/ngc37a.htm#3751 |access-date=2024-05-03 |website=cseligman.com}}
To date, a non-redshift measurement gives a distance of approximately 138,000 Mpc (450 million light-years) for NGC 3751. This value is within the Hubble Distance values.{{Cite web |title=NED Distance Results for NGC 3751 |url=https://ned.ipac.caltech.edu/cgi-bin/nDistance?name=NGC+3751 |access-date=2024-05-03 |website=ned.ipac.caltech.edu}}
Copeland Septet
File:NGC3751 - SDSS DR14.jpg of NGC 3751]]
NGC 3751 is a member of the Copeland Septet.{{Cite web |last=Bakich |first=Michael E. |date=2024-01-01 |title=Copeland's Septet |url=https://www.astronomy.com/science/copelands-septet/ |access-date=2024-05-03 |website=Astronomy Magazine |language=en-US}} The other members are NGC 3745, NGC 3746, NGC 3748, NGC 3750, NGC 3753 and NGC 3754.{{Cite web |title=Copeland's Septet (Hickson Compact Group 57) – Constellation Guide |url=https://www.constellation-guide.com/copelands-septet/ |access-date=2024-05-03 |website=www.constellation-guide.com}}
Halton Arp noticed the 7 galaxies in which he published inside his article in 1966.{{Cite web |title=NED Search Results for ARP 320 |url=https://ned.ipac.caltech.edu/cgi-bin/objsearch?objname=Arp+320&extend=yes&out_csys=Equatorial&out_equinox=B1950.0&obj_sort=RA+or+Longitude&zv=z&zv_breaker=10000.0 |access-date=2024-05-03 |website=ned.ipac.caltech.edu}} This group is known as Arp 320 in which another galaxy, PGC 36010 is part of it.{{Cite web |title=Copeland's Septet (Arp 320) - Astronomy Magazine - Interactive Star Charts, Planets, Meteors, Comets, Telescopes |url=https://cs.astronomy.com/asy/m/galaxies/492462.aspx |access-date=2024-05-03 |website=cs.astronomy.com}}
This group was also observed by Paul Hickson, in which he included them inside his article which was published in 1982.{{Cite journal |last=Hickson |first=P. |date=1982-04-01 |title=Systematic properties of compact groups of galaxies. |url=https://ui.adsabs.harvard.edu/abs/1982ApJ...255..382H |journal=The Astrophysical Journal |volume=255 |pages=382–391 |doi=10.1086/159838 |bibcode=1982ApJ...255..382H |issn=0004-637X}} It is noted that this group is designated as Hickson 57. NGC 3751 is known as HCG 57F.{{Cite web |title=Data from Revised NGC and IC catalogue by Wolfgang Steinicke - NGC 3700 to 3799 |url=http://astrovalleyfield.ca/AstronomieCompl/NGC%20et%20autres/WolfgangS/N3700_exc_web.htm |access-date=2024-05-03 |website=astrovalleyfield.ca}}