NGC 4845
| Galaxie NGC 4845 | |
|---|---|
 (c) ESA/Hubble, CC BY 4.0 | |
| Aufnahme des Hubble-Weltraumteleskops | |
| AladinLite | |
| Sternbild | Jungfrau |
| Position Äquinoktium: J2000.0, Epoche: J2000.0 | |
| Rektaszension | 12h 58m 01,2s[1] |
| Deklination | +01° 34′ 33″[1] |
| Erscheinungsbild | |
| Morphologischer Typ | SA(s)ab / sp HII / LINER[1] |
| Helligkeit (visuell) | 11,3 mag[2] |
| Helligkeit (B-Band) | 12,1 mag[2] |
| Winkelausdehnung | 4′,9 × 1′,3[1] |
| Positionswinkel | 80°[2] |
| Flächenhelligkeit | 13,2 mag/arcmin²[2] |
| Physikalische Daten | |
| Zugehörigkeit | NGC 4753-Gruppe LGG 315 Virgo-II-Gruppe[1][3] |
| Rotverschiebung | 0.003663 ± 0.000009[1] |
| Radialgeschwindigkeit | (1098 ± 3) km/s[1] |
| Hubbledistanz H0 = 73 km/(s • Mpc) | (46 ± 3) · 106 Lj (14,1 ± 1,0) Mpc [1] |
| Durchmesser | 80.000 Lj |
| Geschichte | |
| Entdeckung | William Herschel |
| Entdeckungsdatum | 24. Februar 1786 |
| Katalogbezeichnungen | |
| NGC 4910 • UGC 8078 • PGC 44392 • CGCG 015-049 • MCG +00-33-25 • IRAS 12554+0150 • 2MASX J12580124+0134320 • GC 3330 • H II 536 / H V 3? • h 1491 • LDCE 904 NED285 | |
NGC 4845 ist eine aktive Spiralgalaxie mit ausgedehnten Sternentstehungsgebieten vom Hubble-Typ Sab im Sternbild Jungfrau an der Ekliptik. Sie ist schätzungsweise 46 Millionen Lichtjahre von der Milchstraße entfernt und hat einen Durchmesser von etwa 150.000 Lichtjahren. Die Entfernungsmessungen basierend auf den Radialgeschwindigkeiten stimmen nicht mit den rotverschiebungsunabhängigen Entfernungsschätzungen von etwa 71 ± 15 Millionen Lichtjahren überein.
Das Objekt wurde am 24. Februar 1786 von Wilhelm Herschel entdeckt.[4]
Literatur
- König, Michael & Binnewies, Stefan (2019): Bildatlas der Galaxien: Die Astrophysik hinter den Astrofotografien, Stuttgart: Kosmos, S. 82
Weblinks
Commons: NGC 4845 – Sammlung von Bildern, Videos und Audiodateien
- astronews.com: Bild des Tages 5. Januar 2016
- Supermassive and super-hungry (engl.)
- SIMBAD Astronomical Database
Einzelnachweise
Auf dieser Seite verwendete Medien
Supermassive and super-hungry NGC 4845.jpg
(c) ESA/Hubble, CC BY 4.0
This NASA/ESA Hubble Space Telescope image shows the spiral galaxy NGC 4845, located over 65 million light-years away in the constellation of Virgo (The Virgin). The galaxy’s orientation clearly reveals the galaxy’s striking spiral structure: a flat and dust-mottled disc surrounding a bright galactic bulge. NGC 4845’s glowing centre hosts a gigantic version of a black hole, known as a supermassive black hole. The presence of a black hole in a distant galaxy like NGC 4845 can be inferred from its effect on the galaxy’s innermost stars; these stars experience a strong gravitational pull from the black hole and whizz around the galaxy’s centre much faster than otherwise. From investigating the motion of these central stars, astronomers can estimate the mass of the central black hole — for NGC 4845 this is estimated to be hundreds of thousands times heavier than the Sun. This same technique was also used to discover the supermassive black hole at the centre of our own Milky Way — Sagittarius A* — which hits some four million times the mass of the Sun (potw1340a). The galactic core of NGC 4845 is not just supermassive, but also super-hungry. In 2013 researchers were observing another galaxy when they noticed a violent flare at the centre of NGC 4845. The flare came from the central black hole tearing up and feeding off an object many times more massive than Jupiter. A brown dwarf or a large planet simply strayed too close and was devoured by the hungry core of NGC 4845.
(c) ESA/Hubble, CC BY 4.0
This NASA/ESA Hubble Space Telescope image shows the spiral galaxy NGC 4845, located over 65 million light-years away in the constellation of Virgo (The Virgin). The galaxy’s orientation clearly reveals the galaxy’s striking spiral structure: a flat and dust-mottled disc surrounding a bright galactic bulge. NGC 4845’s glowing centre hosts a gigantic version of a black hole, known as a supermassive black hole. The presence of a black hole in a distant galaxy like NGC 4845 can be inferred from its effect on the galaxy’s innermost stars; these stars experience a strong gravitational pull from the black hole and whizz around the galaxy’s centre much faster than otherwise. From investigating the motion of these central stars, astronomers can estimate the mass of the central black hole — for NGC 4845 this is estimated to be hundreds of thousands times heavier than the Sun. This same technique was also used to discover the supermassive black hole at the centre of our own Milky Way — Sagittarius A* — which hits some four million times the mass of the Sun (potw1340a). The galactic core of NGC 4845 is not just supermassive, but also super-hungry. In 2013 researchers were observing another galaxy when they noticed a violent flare at the centre of NGC 4845. The flare came from the central black hole tearing up and feeding off an object many times more massive than Jupiter. A brown dwarf or a large planet simply strayed too close and was devoured by the hungry core of NGC 4845.