| NGC 3184 | |
|---|---|
 NGC 3184 as observed with theSpitzer Space Telescope, as part of the Spitzer Infrared Nearby Galaxy Survey. The blue colors represent the 3.6 micrometre emission from stars. The green and red colors represent the 5.8 and 8.0 micrometre emission frompolycyclic aromatic hydrocarbons and possibly dustright [clarification needed]. | |
| Observation data (J2000epoch) | |
| Constellation | Ursa Major |
| Right ascension | 10h 18m 17.0s[1] |
| Declination | +41° 25′ 28″[1] |
| Redshift | 0.001975[1] |
| Heliocentric radial velocity | 592 ± 1km/s[1] |
| Distance | 39.8 ± 12 Mly (12.2 ± 3.7 Mpc)[2] |
| Apparent magnitude (V) | 10.4[1] |
| Characteristics | |
| Type | SA(s)b: II |
| Apparent size (V) | 7.4′ × 6.9′ |
| Other designations | |
| UGC 5557, PGC 30087 | |
NGC 3184, also known asThe Little Pinwheel Galaxy, is an unbarredspiral galaxy approximately 40 millionlight-years away[2] in theconstellationUrsa Major. Its name comes from its resemblance to thePinwheel Galaxy. It was discovered by German-British astronomerWilliam Herschel on 18 March 1787.[3] It has twoHII regions namedNGC 3180[4] andNGC 3181.[5]
NGC 3184 houses a high abundance ofheavy elements. The blue color of its spiral arms comes mostly from relatively few bright youngblue stars. The bright stars that highlight the arms were created in huge density waves that circle thecenter.
NGC 3184 has two prominent spiral arms. They have constant pitch angles, which makes them both symmetrical.[6]
Sixsupernovae andastronomical transients have been observed in NGC 3184:
On May 31, 2010, Kōichi Itagaki detected amagnitude 17 optical transient 33" east and 61" north of the center of NGC 3184 at coordinates 10 18 19.89 +41 26 28.8.[17] DesignatedSN 2010dn, this event was initially thought to be an outburstingluminous blue variable (LBV) star,[18] but later analysis categorized it as anintermediate-luminosity red transient (ILRT), also known as aluminous red nova.[19][20] ArchivalHubble andSpitzer images of NGC 3184 seem to show no progenitor for optical transient SN 2010dn.[21] SN 2010dn is just like SN 2008S andNGC 300-OT.[18] On day 2, SN 2010dn had an unfiltered magnitude of 17.1, corresponding to a peakabsolute magnitude of roughly -13.3.[18]
| Name | apmag | type |
|---|---|---|
| SN 1921B | 13.5 | ? |
| SN 1921C | 11.0 | ? |
| SN 1937F | 13.5 | ? |
| SN 1999gi | 14.0 | II |
| SN 2010dn | 17.2 | ILRT |
| SN 2016bkv | 17.2 | II |
| Galaxy | number | Declination |
|---|---|---|
| Arp 299 (NGC 3690 + IC 694) | 14 | +58 |
| NGC 6946 (Fireworks) | 10 | +60 |
| Messier 61 | 8 | +04 |
| Messier 100 | 7 | +15 |
| NGC 3184 | 6 | +41 |
| Messier 83 (Southern Pinwheel) | 6 | −29 |
| NGC 2207 and IC 2163 | 6 | −21 |
| NGC 2276 | 6 | +85 |
| Messier 66 | 5 | +12 |
| Messier 101 (Pinwheel) | 5 | +54 |
| NGC 309 | 5 | −09 |
