NGC 1365

---

title: "NGC 1365" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["barred-spiral-galaxies", "seyfert-galaxies", "luminous-infrared-galaxies", "fornax-cluster", "ngc-objects", "principal-galaxies-catalogue-objects", "fornax", "articles-containing-video-clips", "discoveries_by_james_dunlop", "astronomical-objects-discovered-in-1826"] description: "Galaxy in the constellation Fornax" topic_path: "science/astronomy" source: "https://en.wikipedia.org/wiki/NGC_1365" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Galaxy in the constellation Fornax ::

::data[format=table title="Infobox galaxy"]

Field	Value
name	NGC 1365
image	File:Portrait_of_the_Great_Barred_Spiral.jpg
caption	NGC 1365 imaged by the Cerro Tololo Inter-American Observatory
alt
epoch	J2000
constellation name	Fornax
ra
dec
z
h_radial_v
gal_v
dist_ly	74 Mly
(Light-travel)
group_cluster	Fornax Cluster
type	(R')SBb(s)b{{cite web
title	NASA/IPAC Extragalactic Database
work	Results for NGC 1365
url	http://ned.ipac.caltech.edu/
access-date	2006-11-21}}
mass
mass_light_ratio
size	61.85 to
(diameter; 2MASS K-band total and D25.5 B-band isophotes)
stars
appmag_v	10.3
appmag_b
absmag_v
size_v
half_light_radius_pc
half_light_radius_arcminsec
h1_scale_length_pc
h1_scale_length_arcminsec
xray_radius_pc
xray_radius_arcminsec
names
references
::

| name = NGC 1365 | image = File:Portrait_of_the_Great_Barred_Spiral.jpg | caption = NGC 1365 imaged by the Cerro Tololo Inter-American Observatory | alt = | epoch = J2000 | constellation name = Fornax | ra = | dec = | z = | h_radial_v = | gal_v = | dist_ly = 74 Mly (Light-travel) | group_cluster = Fornax Cluster | type = (R')SBb(s)b{{cite web | title=NASA/IPAC Extragalactic Database | work=Results for NGC 1365 | url=http://ned.ipac.caltech.edu/ | access-date=2006-11-21}} | mass = | mass_light_ratio = | size = 61.85 to (diameter; 2MASS K-band total and D25.5 B-band isophotes) | stars = | appmag_v = 10.3 | appmag_b = | absmag_v = | size_v = | half_light_radius_pc = | half_light_radius_arcminsec = | h1_scale_length_pc = | h1_scale_length_arcminsec = | xray_radius_pc = | xray_radius_arcminsec = | notes = | names = | references =

NGC 1365, also known as the Fornax Propeller Galaxy or the Great Barred Spiral Galaxy,{{cite book |last= Garlick |first= Mark A. |title= Astronomy: A Visual Guide |url= https://archive.org/details/isbn_9781552979587 |url-access= registration |publisher= Firefly Books |date= 2004 |isbn= 978-1-55297-958-7 |page=293

Characteristics

NGC 1365 is a large barred spiral galaxy in the Fornax Cluster. Within the larger long bar stretching across the center of the galaxy appears to be a smaller bar that comprises the core, with an apparent size of about 50 × 40.{{cite book |last= Kepple |first= George Robert |author2=Glen W. Sanner |title= The Night Sky Observer's Guide |volume= 1 |publisher= Willmann-Bell, Inc. |date= 1998 |isbn= 978-0-943396-58-3 |page=198

The spiral arms extend in a wide curve north and south from the ends of the east–west bar and form an almost ring like Z-shaped halo. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the central black hole.

NGC 1365, including its two outer spiral arms, spreads over around 300,000 light-years. Different parts of the galaxy take different times to make a full rotation around the core of the galaxy, with the outer parts of the bar completing one circuit in about 350 million years. NGC 1365 and other galaxies of its type have come to more prominence in recent years with new observations indicating that the Milky Way could also be a barred spiral galaxy. Such galaxies are quite common — two thirds of spiral galaxies are barred according to recent estimates, and studying others can help astronomers understand our own galactic home.

Supernovae

Four supernovae have been observed in NGC 1365:

• SN 1957C (type unknown, mag. 16.5) was discovered by Howard S. Gates on 19 October 1957.
• SN 1983V (Type Ic, mag. 13.5) was discovered by Robert Evans on November 25 1983, and independently discovered by P. O. Lindblad and P. Grosbol on 27 November 1983.
• SN 2001du (Type II, mag. 14) was discovered by Robert Evans on August 24 2001.
• SN 2012fr (Type Ia, mag. 14.7) was discovered by Alain Klotz on October 27 2012.

Supermassive black hole

The central supermassive black hole in the active nucleus, which has a mass of about 2 million solar masses or half the mass of the Milky Way's central black hole Sagittarius A*, rotates at close to the speed of light. These observations, announced in February 2013, were made using the X-ray telescope satellite NuSTAR.

The location of NGC 1365 in the sky

As seen from earth, the location of NGC 1365 is one and a half degrees eastward of STAR 2 (Philip S. Harrington's STAR 2) which is a telescopic asterism in the shape of a triangle, composed of the stars Chi 1-2-3 Fornacis (χ 1-2-3 Fornacis).

References

| author=Jensen, Joseph B. |display-authors=4 | author2=Tonry, John L. | author3=Barris, Brian J. | author4=Thompson, Rodger I. | author5=Liu, Michael C. | author6=Rieke, Marcia J. | author7=Ajhar, Edward A. | author8=Blakeslee, John P. | title=Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations | journal=Astrophysical Journal |date=February 2003 | volume=583 | issue=2 | pages=712–726 | bibcode=2003ApJ...583..712J | doi=10.1086/345430 |arxiv = astro-ph/0210129 |s2cid=551714 }}

References

1. (2014). "interstellarum Deep Sky Atlas". Cambridge University Press; Oculum-Verlag GmbH.
2. NASA, ESA, CSA, STScI, J. Lee (STScI), T. Williams (Oxford), PHANGS Team https://esawebb.org/images/weic2403f/
3. Seligman, Courtney. "NGC 1365".
4. (28 December 2018). "APOD: 2018 December 28 - NGC 1365: Majestic Island Universe". NASA.
5. (22 September 2010}} [[File:CC-BY icon.svg). "An Elegant Galaxy in an Unusual Light". European Southern Observatory.
6. WHIPPLE, F. L.. (1958). "Smithsonian Contributions to Astrophysics".
7. admin. "NGC 1365: The Great Barred Spiral Galaxy {{!}} Constellation Guide".
8. "SN{{nbsp}}1957C". [[International_Astronomical_Union.
9. (1983). "Supernova in NGC 1365". International Astronomical Union Circular.
10. (1983). "Supernova in NGC 1365". International Astronomical Union Circular.
11. "SN{{nbsp}}1983V". [[International_Astronomical_Union.
12. "Supernova 2001du in NGC 1365".
13. (2001). "Supernova 2001du in NGC 1365". International Astronomical Union Circular.
14. "SN{{nbsp}}2001du". [[International_Astronomical_Union.
15. (2012-10-01). "Supernova 2012fr in NGC 1365 = Psn J03333599-3607377". Central Bureau Electronic Telegrams.
16. Reynolds, Christopher. (2013). "Astrophysics: Black holes in a spin". Nature.
17. [https://arxiv.org/ftp/arxiv/papers/1302/1302.7002.pdf - Unambiguous Determination of the Spin of the Black Hole in NGC 1365]

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