21 March 2016

'Someone' Is Trying to Get Our Attention

11 Adar II 5776

"Hey! All you people looking down at your devices! Look up here!!"

On March 21st, green comet 252P/LINEAR will fly by Earth only 5.4 million km away-- the fifth closest cometary approach on record. One day later, a suspected fragment of the comet will pass even closer (3 million km). The name of the fragment is "P/2016 BA14,"....

By all accounts, the comet fragment is "pitifully faint." The parent comet, however, is relatively bright. Indeed, it is now on the threshold of naked eye visibility for observers in the southern hemisphere.

...The comet is green because its vaporizing nucleus emits diatomic carbon, C2, a gas which glows green in the near-vacuum of space. The verdant color will become even more intense in the nights ahead as 252P/LINEAR approaches Earth.

There is a chance that the comet's approach could cause a minor meteor shower. According to the International Meteor Organization, "[modeling by forecaster] Mikhail Maslov indicates that there might be a weak episode of faint, very slow meteors (15.5 km/s) on March 28–30 from a radiant near the star μ Leporis." Little is known about meteors from this comet, so estimates of the meteor rate are very uncertain. Maslov's models suggest no more than 5 to 10 per hour.  (Source)