NGC 309

{{Short description|Spiral galaxy located in the constellation Cetus}}

{{Use mdy dates|date=October 2016}}

{{Sky|00|56|42.653|-|09|54|49.883}}

{{Infobox galaxy

| name = NGC 309

| image = File:NGC309 - SDSS DR14.jpg

| caption = SDSS image of NGC 309

| epoch = J2000

| ra = {{RA|00|56|42.653}}{{cite web

| title=NASA/IPAC Extragalactic Database

| work=Results for NGC 0309

| url=https://ned.ipac.caltech.edu/byname?objname=ngc+309

| access-date=September 2, 2016}}

| dec = {{DEC|-09|54|49.883}}

| dist_ly = {{convert|26.978 ± 3.205|Mpc|Mly|abbr=on|lk=on|order=flip}}

| constellation name = Cetus

| z = 0.018883

| h_radial_v = 5661 ± 2 km/s

| type = SAB(r)c

| appmag_v = 13.4g

| size_v = {{Val|1.94|×|1.34|u=arcminute}}

| size=~{{convert|24.81|kpc|ly|abbr=on|lk=on|order=flip}} (estimated)

| notes =

| names = {{odlist | MCG= -02-03-050 | 2MASX= J00564266-0954500 | IRAS= 00542-1010 | PGC= 3377 | name= HOLM 027A}}

}}

NGC 309 is a spiral galaxy in the constellation Cetus. Its velocity with respect to the cosmic microwave background is 5343 ± 22{{nbsp}}km/s, which corresponds to a Hubble distance of {{convert|78.81 ± 5.53|Mpc|Mly|abbr=on|lk=on|order=flip}}. However, nine non-redshift measurements give a much closer distance of {{convert|26.978 ± 3.205|Mpc|Mly|abbr=on|lk=on|order=flip}}.{{cite web | url = https://ned.ipac.caltech.edu/cgi-bin/nDistance?name=NGC+309 | title = Distance Results for NGC{{nbsp}}309 | website = NASA/IPAC EXTRAGALACTIC DATABASE | publisher = NASA | access-date = 22 November 2024}} It was discovered in 1876 by Wilhelm Tempel.{{cite web|title=New General Catalog Objects: NGC 300 - 349|url=http://cseligman.com/text/atlas/ngc3.htm#309|publisher=Cseligman|access-date=October 20, 2016}}

NGC 309 and NGC 309A are listed together as Holm 27 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937.{{cite journal | bibcode=1937AnLun...6....1H | title=A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems | last1=Holmberg | first1=Erik | journal=Annals of the Observatory of Lund | date=1937 | volume=6 | page=1 }}