IC 860

IC 860 is a barred spiral galaxy in the constellation of Coma Berenices. It is located 155 million light years away from Earth.^[1] It was discovered on June 16, 1892, by Stephan Javelle, a French astronomer.^[2] It is a peculiar galaxy.^[3]

IC 860
SDSS image of IC 860
Observation data (J2000 epoch)
Constellation	Coma Berenices
Right ascension	13h 15m 03.50s
Declination	+24° 37′ 07.79″
Redshift	0.012909
Heliocentric radial velocity	3,870 km/s
Distance	155 Mly (47.52 Mpc)
Apparent magnitude (V)	0.044
Apparent magnitude (B)	0.057
Characteristics
Type	Sa, HII;LIRG
Size	35,000 ly
Apparent size (V)	0.5' x 0.3'
Notable features	luminous infrared galaxy
Other designations
CGCG 130-023, IRAS 13126+2452, ECO 03976, MCG +04-31-015, PGC 46086

IC 860 is classified a nearby post-starburst galaxy, in early stages of transforming into its quiescent state.^[4] It is also vibrationally excited HCN luminous infrared galaxy (LIRG) with L_HCN -_VIB/L_IR of 3.2 x 10⁻⁸. It has a dust obscured nucleus making it hard to determine whether it is a starburst galaxy or an active galactic nucleus (AGN).^[5] In additional, the galaxy contains HI and OH absorption towards its central region. The galaxy has an implied mass of M_SMBH of 4 x 10⁷ M_Θ based on its velocity rotation of v_rot = 226 km s⁻¹. The Eddington luminosity of IC 860 is 2 x 10¹² L_Θ.^[6]

According to low [C II] 157.7 μm-to-L_FIR ratios and by a mid-infrared silicate absorption, the findings suggest IC 860 does have a warm compact region. The region of the galaxy, is in a current phase of rapid evolution where inflows are accumulating column densities of interstellar dust and gas, sufficient to fuel its star formation or its AGN.^[6]

IC 860 was also observed in optical imaging. From the results, the galaxy has a massive V-shaped kiloparsec dust structure. As the nuclear gas only has an outflow velocity of v_out = 170 – 200 km s⁻¹, this makes it impossible to escape from the galaxy unless being accelerated.^[6]

In another study, IC 860 contains 4.83 GHz formaldehyde emission with a peak flux density of 2.0-2.2 mJy based from observations made by Arecibo Observatory. It is found to have three unique emission compartments centered between 3830 and 3990 km s⁻¹.^[7]