## Saturday, 3 April 2021

### Super Nova

 Kepler's Supernova* remnant in background

There is a unified catalogue of 5526 supernova (SN) by D. Lennarz et al and I want to extract the Type Ia Super Novae along with their magnitudes, redshifts and distances to see how those compare with what I have been learning out about redshifts and luminosity and other distances in section 8.3. Type Ia Super Nova are all supposed to have the same absolute magnitude of −19.3 (about 5 billion times brighter than the Sun). I was able to confirm Hubble's law and learnt that that the mighty peculiar formula for Type Ia Supernova: $m=5\log_{10}{D}-24.3$ for the fall off in apparent magnitude $m$ with distance $D$ is in fact an inverse power law. And that corrections for the expansion and curvature of the universe at this range (about a fifteenth of the size of the visible universe) are immaterial.