Worldwide pro-am help sought for comet trio study

Amateur and professional astronomers are invited to provide observations of comets 41P/Tuttle-Giacobini-Kresák, 45P/Honda-Mrkos-Pajdušáková, and 46P/Wirtanen that will pass by Earth at distances ranging from 0.08 to 0.15 astronomical units. Such close approaches of a trio of comets within the next two years are rare and typically occur only once every few decades.

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SOHO sees bright sungrazer comet

ESA and NASA’s Solar and Heliospheric Observatory, or SOHO, saw a bright comet plunge toward the Sun on 3-4 August 2016, at nearly 1.3 million miles per hour. The comet, first spotted by SOHO on 1 August, is part of the Kreutz family of comets, a group with related orbits that broke off of a huge comet several centuries ago.


How comets break up and make up

For some comets, breaking up is not that hard to do. A new study indicates that the bodies of some periodic comets — objects that orbit the Sun in less than 200 years — may regularly split in two, then reunite down the road. This may be a repeating process fundamental to comet evolution.


Pluto’s interactions with the solar wind are unique

Using data gathered by NASA’s New Horizons spacecraft on its Pluto flyby in July 2015, the dwarf planet has some characteristics less like that of a comet and more like much larger planets, according to the first analysis of Pluto’s unique interaction with the solar wind — the charged particles that spew off from the Sun into the solar system at a supersonic 1 million mph.


See Comet 252P/LINEAR in a moonless sky

On the afternoon of 21 March, Comet 252P/LINEAR brushed by Earth just 14 lunar distances away. The comet’s separation from Earth now exceeds 20 million miles, but it’s still a suitable target for binoculars and small telescopes — if you know exactly where to look. Here’s our UK observing guide for 252P/LINEAR in the constellation Ophiuchus between midnight and moonrise over the coming week.