Regulus and the Red Planet . ... Credit Copyright: Babak Tafreshi ( TWAN ) Explanation: Leo's royal star Regulus and red planet Mars appear in a colorful pairing just above the horizon in this starry skyscape. ... The marked color contrast between Mars and the bright blue star was easy to discern by eye, but is further enhanced in the picture through the use of a diffusion filter. ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ...