June Comet

HYPERBOLIC COMET JOHNSON: Discovered in November 2015 by Jess Johnson of the Catalina Sky Survey, Comet Johnson (C/2015 V2) is now swinging through the inner solar system on a hyperbolic orbit. A "hyperbolic orbit" means the sun's gravity will probably fling the comet into deep space later this year.  Now is the time to look.  Amateur astronomer Rolando Ligustri used a remotely controlled telescope in New Mexico to photograph the comet on May 1st:

Ligustri's 2 x 10 minute exposure with a 4 inch telescope reveals the comet's green nucleus and its double tail. The longer of the two is the filamentary ion tail, made of gas carried directly away from the sun by the solar wind. The shorter protuberance is the bright dust tail, made of dusty-rocky grains sprinkled like crumbs along the comet's orbit. Comet Johnson's nucleus is green because it contains diatomic carbon (C2) a substance that glows with a verdant hue in the near vacuum of space.
This comet is not visible to the naked eye, but as it approaches Earth for a 0.81 AU close encounter in early June, it is brightening to ~6th magnitude, making it an easy target for backyard telescopes. Northern hemisphere observers are favored in early May, when the comet dwells in the constellation Hercules; in late May and June, Comet Johnson races toward southern skies, where observers south of the equator can watch the comet continue its journey toward the sun. Resources: sky maps, 3D orbit, magnitudes.