Comet Lulin (official designation C/2007 N3 (Lulin), Traditional Chinese:鹿林彗星) is a non-periodic comet. It was discovered by Ye Quanzhi and Lin Chi-Sheng from Lulin Observatory. It peaked in brightness and arrived at perigee for observers on Earth on February 24, 2009, at magnitude +5, and at 0.411 AU from Earth. The comet was near conjunction with Saturn on February 23, and passed near Regulus in the constellation of Leo on February 26 and 27, 2009. It was expected to pass near Comet Cardinal on May 12, 2009. The comet became visible to the naked eye from dark-sky sites around February 7. It passed near the double star Zubenelgenubi on February 6, near Spica on February 15 and 16, near Gamma Virginis on February 19 and near the star cluster M44 on March 5 and 6. It also passed near the planetary nebula NGC 2392 on March 14, and near the double star Wasat around March 17. According to NASA, Comet Lulin's green colour comes from a combination of gases that make up its local atmosphere, primarily diatomic carbon, which appears as a green glow when illuminated by sunlight in the vacuum of space.