This is a re-posting of the wrap-up article which appeared on the IYL2015 main blog.
2015 has been the International Year of Light.
As astronomers, here at the Sloan Digital Sky Survey everything we do is based on collecting light from cosmic objects. So we have been pleased to celebrate the International Year of Light, and especially the Cosmic Light Theme, supported by the IAU.As a small contribution to this celebration, every month in 2015 SDSS had a special blog post talking about the different ways we use light. Here’s a roundup of what we talked about through out the year.
In January we talked about How SDSS Uses Light to Study the Darkest Objects in the Universe. This blog post, by Coleman Krawcyzk and Karen Masters (both from the University of Portsmouth in the UK) with help from Nic Ross (Royal Observatory, Edinburgh) was about finding black holes by looking at the light from distant galaxies. Finding objects which are famous for not emitting any light, using light seems contradictory, but this article explains how the light created by the hot material falling onto a black hole can make these objects outshine the entire galaxy they live ...