NGC 309 explained

NGC 309
Epoch:	J2000
Ra:	^[1]
Dist Ly:	NaNMpc
Constellation Name:	Cetus
Z:	0.018883
H Radial V:	5661 ± 2 km/s
Type:	SAB(r)c
Appmag V:	13.4g
Size:	~24.81kpc (estimated)

NGC 309 is a spiral galaxy in the constellation Cetus. Its velocity with respect to the cosmic microwave background is 5343 ± 22km/s, which corresponds to a Hubble distance of NaNMpc. However, nine non-redshift measurements give a much closer distance of NaNMpc.^[2] It was discovered in 1876 by Wilhelm Tempel.^[3]

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.^[4]

Supernovae

Five supernovae have been observed in NGC 309.

Supernovae in NGC 309! Supernova! apmag! type! Discovery date

1999ge^[5]	15.5		27 November 1999
2008cx^[6]	17.8		5 June 2008
2012dt^[7]	18.0		17 July 2012
PSN J00564446-0954595^[8]	17.2	IIb	10 June 2013
2014ef^[9] ^[10]	17.3		13 December 2014

See also

• List of NGC objects (1–1000)

Notes and References

1. Web site: NASA/IPAC Extragalactic Database . Results for NGC 0309 . September 2, 2016.
2. Web site: Distance Results for NGC309 . NASA/IPAC EXTRAGALACTIC DATABASE . . 22 November 2024.
3. Web site: New General Catalog Objects: NGC 300 - 349. Cseligman. October 20, 2016.
4. 1937AnLun...6....1H . A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems . Holmberg . Erik . Annals of the Observatory of Lund . 1937 . 6 . 1 .
5. Web site: Transient Name Server . SN1999ge . . 22 November 2024.
6. Web site: Transient Name Server . SN2008cx . . 22 November 2024.
7. Web site: Transient Name Server . SN2012dt . . 22 November 2024.
8. Web site: FIRE Classification of Supernova in NGC 309 . Fox . Derek . 17 June 2013 . The Astronomer's Telegram . 22 November 2024.
9. https://www.rochesterastronomy.org/sn2014/index.html#2014ef 2014ef
10. Web site: Transient Name Server . SN2014ef . . 22 November 2024.