The brightness class of NGC 918 is III and it has a broad line of neutral hydrogen. NGC 918 is also an active nucleus galaxy (AGN). Moreover, it is afield galaxy which does not belong to a cluster or group and is therefore gravitationally isolated.[5]
Many non-redshift measures give a distance of 19,115 ± 6,160 Mpc (~62,3 million ly),[6] which is within the distances calculated using the value shift.[2]
SN 2009js (type II, mag. 17.2) was discovered byKōichi Itagaki and independently by theLick Observatory Supernova Search (LOSS) on October 11, 2009.[7][8][9][10][11] This was the first subluminous supernova to be studied in infrared wavelengths.[10]
SN 2011ek (type Ia, mag. 16.4) was discovered by Kōichi Itagaki on Aug. 4, 2011.[12][13][14]
^abWe obtain the distance that separates us from a galaxy using Hubble's law: v = Hod, where Ho is the Hubble constant (70 ± 5 (km / s) / Mpc). The relative uncertainty Δd / d over the distance is equal to the sum of the relative uncertainties of the velocity and Ho.
Media related toNGC 918 at Wikimedia Commons
