Saturday 8 March 2014

Knots in the Plasma Tail of Comet C/2013 R1(Lovejoy).

Comet C/2013 R1 (Lovejoy) was discovered on 7 September 2013 by talented Australian amateur astronomer Terry Lovejoy (who to date has discovered for new comets). It is a long period comet, thought to visit the inner Solar System roughly once every 20 years, when it reaches 0.58 AU from the Sun (58% of the distance between the Earth and the Sun, between the orbits of Venus and Mercury), before returning to the outer Solar System, eventually reaching 1063 AU from the Sun (1063 times as far from the Sun as the Earth, or more than 35 times as far from the Sun as Neptune, the outermost planet).

In a paper published on the online arXiv database at Cornell University Library on 6 March 2014, a team of scientists led by Masafumi Yagi of the National Astronomical Observatory of Japan describe the results of an observation of C/2013 R1 (Lovejoy) made on 4 December 2013, using the Subaru Telescope on Mauna Kea, Hawaii, which detected two knots (patches of denser material) in the tail of the comet, roughly 300 000 km from the head, moving away from the head at speeds of 21 and 24 km per second respectively.

Such knots have been described in the tails of a number of comets previously, but all have been much further from the head, and moving at far greater speeds. It ha previously been thought that such knots accelerated as they moved away from the comet, which this new observation would appear to confirm.

Image of Comet C/2013 R1 (Lovejoy) produced using the Subaru Telescope on Mauna Kea. Yagi et al. (2014).

See also The breakup of Main Belt object P/2013 R3 (Catalina-Pan STARRS), The nateure and hostory of 'Quasi-Hilda Object' 2000 YN30, The perihelion of comet ISON (C/2012 S1), The perihelion of Comet 103P/Hartley 2 and The origin of Comet P/2006 VW139.

Follow Sciency Thoughts on Facebook.