Heinrich d'Arrest discovered NGC 1 on 30 Sep 1861 while testing the 11-inch f/17.5 Merz refractor of the Copenhagen Observatory. He missed nearby NGC 2. This was d'Arrest's first deep sky discovery, though he was uncertain if his object was identical to h4 or h5 (both of which refer to NGC 16). His descriptions (combination of 4 observations) read "faint, small, round, 20", no concentration. In a straight line connecting two stars 11 and 14 mag." Herman Schultz observed NGC 1 three times in 1866 and 1868 with a 9.6-inch refractor at Uppsala and he also missed fainter NGC 2. The NGC 1 and 2 pair are not physically related. NGC 1 lies at a distance of about 200 millionlight-years (61 Mpc) with NGC 2 at roughly 320 millionlight-years (98 Mpc).[5]
The initial observers missedNGC 2, which is much fainter. NGC 1 appears to be quite close to NGC 2, in reality however, the two objects are far apart and unrelated. NGC 2 was first observed as a "companion" of NGC 1 byLawrence Parsons.[4]
At an estimated 140,000 light-years in diameter,[4] NGC 1 is roughly the same size as our galaxy, theMilky Way, which is believed to be approximately 160,000 light-years across.[6] Although itsapparent magnitude of 13.65 makes the galaxy appear too faint to see with the naked eye, itsabsolute magnitude of -22.08 makes NGC 1 two to three times moreluminous than our home galaxy. The galaxy is 4.0 Mly away from the 80,000 light-years wide galaxyUGC 69, its nearest major neighbor.
NGC 1 has a visual size of 1.6' × 1.2'.[1] Beingclassified as a SABbc class galaxy using theHubble sequence and theDe Vaucouleurs system as an extension, NGC 1 is a spiral galaxy with the presence of a weaknuclear bar and loosely wound arms.[7] Although the central galaxy is only about 90,000 light-years across, a large, diffuse arm extends eastwards from it, possibly from a past merger.
Based on itsredshift of approximately 0.015177 and thusrecessional velocity of 4450 km/s,[1] the distance of the galaxy from the Solar System can be calculated usingHubble's law. Using current observation data, this places the galaxy at approximately 210 to 215 million light-years from Earth, which is in good agreement with redshift-independent distance estimates of 175 to 245 million light years. An opposing measurement of the galaxy's recessional velocity of 2215 km/s would place the galaxy only about 100 million light-years away. However, this is regarded unlikely by most astronomers and believed to be a misattributed value for a different galaxy.[4]
After being logged as the first object in theGeneral Catalogue, the galaxy is also the first object to be listed in the catalogue's successor, theNew General Catalogue.[1] With an originalright ascension of00h 00m 4s at the time of the catalog's compilation (epoch 1860), this object had the lowest right ascension of all the objects in the catalog, making it the first listing in the New General Catalogue as the objects were arranged by right ascension.[8] Since then, the coordinates have shifted, and this object no longer has the lowest right ascension of all the NGC objects.[9]
^Dreyer, J. L. E., "New General Catalogue of Nebulae and Clusters of stars (1888)",Memoirs of the Royal Astronomical Society,49. p3, Royal Astronomical Society, 1962.
^Erdmann, R.E., Jr.,The Historically Corrected New General Catalogue of Nebulæ and Clusters of Stars, p12,retrieved andarchived 13 June 2008.
^Garcia, A. M. (1993). "General study of group membership. II. Determination of nearby groups".Astronomy and Astrophysics Supplement Series.100: 47.Bibcode:1993A&AS..100...47G.
