NGC 1012

NGC 1012 is a lenticular galaxy in the Constellation Aries. It was discovered on September 11, 1784 by William Herschel, and observed again by John Herschel. John Louis Emil Dreyer described it as faint, pretty small, irregularly round, brighter middle, star involved.

NGC 1012 has a diameter (kiloparsec) of 12.79 and has an inclination of 77±4°, indicating it is a small edge-on galaxy.

Properties In the ALFALFA neutral hydrogen (HI) survey, NGC 1012 is detected to have an integrated neutral hydrogen (HI) flux of 46.39±0.13 Jy km s⁻¹ (polygon) and 43.76 Jy km s⁻¹ (pipeline). The neutral hydrogen (HI) disk has a diameter of 1.6' and the HI mass is approximately 2.5× M⊙, indicating it is a gas rich galaxy.

Using Green Bank Observatory's 43m telescope to detect NGC 1012's 21cm HI profiles found that NGC 1012 has a HI flux of 90.41 Jy km/s, significantly higher than the ALFALFA survey.

NGC 1012 has a stellar mass (log M∗) of 9.14 (1.4×M⊙), a star formation rate (SFR) (log SFR) of −0.158 (0.70 M⊙ yr⁻¹) and an Xray luminosity of log =39.74 erg s⁻¹ with a probability of 0.26% that the X-ray emission originates from X-ray binaries, suggesting an Active Galactic Nucleus or hot-gas origin.

Using data from the Gassendi H Alpha survey of Spirals (GHASP), NGC 1012 has a far-ultraviolet flux of 23.0 ± 2.7 × 10⁻¹⁶ W m⁻², indicating hot, young and massive stars within the galaxy. There are two sources within NGC 1012 that is identified as a candidate ultraluminous X-ray source (ULX). The brighter source is near the center of the galaxy, while the dimmer source is far out on the disk. The brighter source has a signal-to-noise S/N of 9.2 and count-based luminosity of 5.7× erg/s while the dimmer source has a S/N = 3.8 and =1.1× erg/s, possibly an intermediate-mass black hole.

NGC 1023 and LGG 67 Group NGC 1012 is part of a galaxy group known as the NGC 1012 Group or LGG 67. It has at least 3 members, which are NGC 1012, UGC 2017 and UGC 2053.

Another paper states that NGC 1012 is part of a galaxy group known as the NGC 1023 Group, but NGC 1012's systematic velocity is 1120 km and NGC 1023's velocity is 776 km , indicating it is probably lying at the near-edge of the NGC 1023 Group.

Gallery

NGC 1012

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