Astronomical data · SIMBAD
- Object type
- GiG
- Redshift
- z = 0.010764
- Morphology
- S_AB
- Coordinates
- RA 214.6071° · Dec 36.4937°
via SIMBAD · CDS Strasbourg
Key facts
- Constellation
- Boötes
- Right ascension
- 14 18 25.708
- Declination
- +36 ° 29 ′ 37.28 ″
- Heliocentric radial velocity
- 3210 ± 28 km/s
- Distance
- 127 Mly (38.8 Mpc )
- Absolute magnitude v
- − 22.39
- Type
- E1
via Wikipedia infobox
Wikidata facts
- Instance of
- elliptical galaxy
- Constellation
- Boötes
- Distance from Earth
- 51.11
- Image
- NGC5557 - SDSS DR14.jpg
Show 11 more facts
- catalog code
- LEDA 51104
- radial velocity
- 3210
- discoverer or inventor
- William Herschel
- time of discovery or invention
- 1785-05-01
- redshift
- 0.010867
- galaxy morphological type
- -1
- apparent magnitude
- 10.582
- right ascension
- 214.6071167
- declination
- 36.4936889
- epoch
- J2000.0
- Commons category
- NGC 5557
Sources (1)
via Wikidata · CC0
~1 min read
Encyclopedic overview
NGC 5557 is an elliptical galaxy in the constellation Boötes. It was discovered by William Herschel on May 1, 1785. The distance to NGC 5557 is not well known, but it is estimated to be about 127 million light-years (38.8 megaparsecs) away.
NGC 5557 is quite massive, with a K-band absolute magnitude of −24.8, and is a slow rotator, which suggests it gained mass through dry mergers (galaxy mergers involving galaxies significant amounts of gas). However, it has a faint tidal tail to its east, as well as a more complex structure to the west. This structure, if found to be connected to NGC 5557, would one of the largest around a galaxy, spanning about 1.1 million light-years (350,000 parsecs). This filamentary structure suggests that NGC 5557 may have formed from a more gas-rich galaxy merger a couple billion years ago. This implies that the galaxy merger would need to have a low impact parameter.
Excerpted from Wikipedia’s “NGC 5557” article, available under the CC BY-SA 4.0 licence.