NGC 747

{{Short description|Galaxy in the constellation Cetus}}

{{Infobox galaxy

| image = NGC747 - SDSS DR14.jpg

| name = NGC 747

| epoch = J2000

| ra = 01h 57m 29s

| dec = -09° 27{{prime}} 45{{pprime}}

| sbrightness = 23.05 mag/arcsec2

| appmag_b = 14

|constellation name=Cetus|z=0.0179|names=PGC 7366, 2MASX J01573044-0927444, MCG -02-06-007, SDSS J015730.45-092744.5}}

NGC 747 is a spiral galaxy located in the constellation Cetus.{{Cite web |title=NGC 747 - Spiral Galaxy in Cetus {{!}} TheSkyLive.com |url=https://theskylive.com/sky/deepsky/ngc747-object |access-date=2024-04-16 |website=theskylive.com}} Its speed relative to the cosmic microwave background is 5,100 ± 19 km/s, which corresponds to a Hubble distance of 75.2 ± 5.3 Mpc (~245 million ly).{{Cite web |last=Astronomy |first=Go |title=NGC 747 {{!}} galaxy in Cetus {{!}} NGC List {{!}} GO ASTRONOMY |url=https://www.go-astronomy.com/ngc.php?ID=795 |access-date=2024-04-16 |website=Go-Astronomy.com |language=en-US}} NGC 747 was discovered by American astronomer Francis Leavenworth in 1886.{{Cite web |title=New General Catalog Objects: NGC 700 - 749 |url=https://cseligman.com/text/atlas/ngc7.htm#747 |access-date=2024-04-25 |website=cseligman.com}} The luminosity class of NGC 747 is II and it has a broad HI line.{{Cite web |title=NGC 747 |url=https://simbad.cds.unistra.fr/simbad/sim-basic |access-date=2024-04-16 |website=simbad.cds.unistra.fr}} To date, four non-redshift measurements yield a distance of 83.900 ± 4.166 Mpc (~274 million ly), which is within the Hubble distance range.{{Cite web |title=NGC 747 |url=https://spider.seds.org/ngc/ngc.cgi?747 |access-date=2024-04-16 |website=spider.seds.org}} Note, however, that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy and that consequently the diameter of NGC 747 could be approximately 23 .9 kpc (~78,000 ly).{{Cite web |last=Ford |first=Dominic |title=NGC747 (Galaxy) |url=https://in-the-sky.org//data/object.php?id=NGC747 |access-date=2024-04-16 |website=In-The-Sky.org |language=en}} In the same area of the sky there are, among other things: the galaxies NGC 713, NGC 731, NGC 755 and NGC 767.