But rather on the warm side

http://hyperphysics.phy-astr.gsu.edu/hbase/astro/redgia.html#c2
http://www.physics.uc.edu/~hanson/ASTRO/LECTURENOTES/W03/Lec10/Page1.html
http://www.thenightland.co.uk/nightdarkening.html
http://www.omniology.com/IMAGOLUTIONARY-SolarSystems.html
