Difference between revisions of "Whirlpool Galaxy"
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{{Night Sky | {{Night Sky | ||
| image =Messier51 sRGB.jpg | | image =Messier51 sRGB.jpg | ||
| − | | designation =[[Messier catalogue|Messier 51]] | + | | designation =[[Messier catalogue|Messier 51]]<br/>[[NGC]] 5194 |
| − | [[NGC]] 5194 | ||
| rightascension =13<sup>h</sup> 29<sup>m</sup> 52.7<sup>s</sup> | | rightascension =13<sup>h</sup> 29<sup>m</sup> 52.7<sup>s</sup> | ||
| declination =+47° 11′ 43″ | | declination =+47° 11′ 43″ | ||
| − | | constellation =Canes Venatici | + | | constellation =[[Canes Venatici]] |
| − | | type = [[Spiral galaxy]] | + | | type =[[Spiral galaxy]] |
| − | | dimensions = 11.2 x 6.9' | + | | dimensions =11.2 x 6.9'<ref name=messier-objects>[http://www.messier-objects.com/messier-51-whirlpool-galaxy/ M51] from messier-objects.com</ref> |
| − | | magnitude =8.4 | + | | magnitude =Apparent Mag: +8.4<ref name=messier-objects/><br/>Absolute Mag: |
| − | | redshift =0. | + | | redshift =0.00155±0.00020<ref name=simbad>[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=M51&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id M51] from simbad.u-strasbg.fr</ref> |
| − | | distance = | + | | distance =23±4 million light years<ref name=constellation-guide>[http://www.constellation-guide.com/whirlpool-galaxy-messier-51/ Whirlpool galaxy] from constellation-guide.com</ref> |
| − | | radvelocity = | + | | radvelocity =463±3 km/s<ref name=messier-objects/><ref name=simbad/> |
| propmotion = | | propmotion = | ||
| − | | parallax = | + | | parallax =7.8±16.9 mas<ref name=simbad/> |
}} | }} | ||
| − | The '''Whirlpool galaxy''' (M51, NGC 5194) is a [[spiral galaxy]] in the [[constellation]] of Canes Venatici.<ref name=messier-objects | + | The '''Whirlpool galaxy''' (M51, NGC 5194) is a [[spiral galaxy]] in the [[constellation]] of [[Canes Venatici]].<ref name=messier-objects/> it is one of the most spectacular galaxies known and one of the easiest to find. It is sometimes called the "Question mark galaxy."<ref name=messier-objects/> The larger galaxy is catalogued as NGC 5194 in the New General catalogue while the smaller galaxy is NGC 5195. Messier 51 can refer to NGC 5194 or both galaxies, though it usually is just NGC 5194. Sometimes NGC 5194 is also called M51a and NGC 5195 is called M51b. It was the first spiral galaxy ever discovered.<ref name=messier-objects/> |
==History== | ==History== | ||
| − | The larger galaxy, NGC 5194 was discovered [[Charles Messier]] in 1773 while he was attempting to observe a [[comet]].<ref name=constellation-guide | + | The larger galaxy, NGC 5194 was discovered [[Charles Messier]] in 1773 while he was attempting to observe a [[comet]].<ref name=constellation-guide/> The smaller galaxy was discovered later in 1781 by Messier's colleague, Pierre Méchain. Messier was not able to identify any [star]]s stating the object was a, "very faint nebula without stars." It was not until 1845 that William Parsons' Leviathan, a 72 inch reflecting [[telescope]] identified a spiral structure, the first observed.<ref name=messier-objects/> Wlliam Parsons was the 3<sup>rd</sup> Earl of Rosse, giving another name form the object of "Rosse's galaxy." |
==Environment and Structure== | ==Environment and Structure== | ||
Revision as of 14:43, December 29, 2017
| Whirlpool Galaxy | |
|---|---|
| |
| Observational Data | |
| Designation | Messier 51 NGC 5194 |
| Right ascension | 13h 29m 52.7s |
| Declination | +47° 11′ 43″ |
| Constellation | [[Canes Venatici]] |
| Type of object | [[Spiral galaxy]] |
| Dimensions | 11.2 x 6.9'[1] |
| Magnitude | Apparent Mag: +8.4[1] Absolute Mag: |
| Redshift | 0.00155±0.00020[2] |
| Astrometry | |
| Distance from Earth | 23±4 million light years[3] |
| Radial velocity | 463±3 km/s[1][2] |
| Parallax | 7.8±16.9 mas[2] |
The Whirlpool galaxy (M51, NGC 5194) is a spiral galaxy in the constellation of Canes Venatici.[1] it is one of the most spectacular galaxies known and one of the easiest to find. It is sometimes called the "Question mark galaxy."[1] The larger galaxy is catalogued as NGC 5194 in the New General catalogue while the smaller galaxy is NGC 5195. Messier 51 can refer to NGC 5194 or both galaxies, though it usually is just NGC 5194. Sometimes NGC 5194 is also called M51a and NGC 5195 is called M51b. It was the first spiral galaxy ever discovered.[1]
History
The larger galaxy, NGC 5194 was discovered Charles Messier in 1773 while he was attempting to observe a comet.[3] The smaller galaxy was discovered later in 1781 by Messier's colleague, Pierre Méchain. Messier was not able to identify any [star]]s stating the object was a, "very faint nebula without stars." It was not until 1845 that William Parsons' Leviathan, a 72 inch reflecting telescope identified a spiral structure, the first observed.[1] Wlliam Parsons was the 3rd Earl of Rosse, giving another name form the object of "Rosse's galaxy."
Environment and Structure
The Whirlpool galaxy has a diameter of 60,000 light years and an estimated mass of 160 billion solar masses.[3][4] This is around 35% the size of the Milky Way. The distance across both galaxies is about 75,000 light years. The smaller galaxy, NGC 5195 is a dwarf galaxy and classified as an irregular galaxy.
The galaxy is believed to have a supermassive black hole at its centre. The galactic core is fairly active, meaning it is a Seyfert galaxy spcefically, type 2.5.[5][6]
References
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