‘Twin Comets’ to Safely Fly Past Earth
Two Jupiter-family comets – 252P/LINEAR and P/2016 BA14 (PANSTARRS) – will safely fly past Earth on March 21 and 22, 2016 at a distance of 5.2 million km (3.3 million miles) and 3.5 million km (2.2 million miles), respectively. The two comets have intriguingly similar orbits and were thus dubbed “twin comets.”
Comet P/2016 BA14, discovered on January 22, 2016, was initially thought to be an asteroid, but follow-up observations showed a faint tail, revealing that the discovery was, in fact, a comet. 7
The orbit of this newly discovered comet follows an unusually similar orbit to that of comet 252P/LINEAR, which was discovered on April 7, 2000, and the apparent coincidence may be an indication of twin nature in that comet. P/2016 BA14 is roughly half the size of comet 252P/LINEAR and might be a fragment that calved off sometime in the larger comet’s past.
“Comet P/2016 BA14 is possibly a fragment of 252P/LINEAR. The two could be related because their orbits are so remarkably similar,” said Paul Chodas, manager of NASA’s Center of NEO Studies (CNEOS) at the JPL.
“We know comets are relatively fragile things, as in 1993 when comet Shoemaker-Levy 9 was discovered and its pieces linked to a flyby of Jupiter. Perhaps during a previous pass through the inner Solar System, or during a distant flyby of Jupiter, a chunk that we now know of as BA14 might have broken off of 252P.”
Observations made by the Hubble Space Telescope of comet 252P/LINEAR, and by NASA’s Infrared Telescope Facility of comet P/2016 BA14 will further investigate their possible twin nature.
Comet 252P/LINEAR, approximately 230 meters (750 feet) in size, will zip past Earth at 13:15 UTC on Monday, March 21 at a range of about 5.2 million km (13.9 LD / 3.3 million miles). The relative velocity of this comet is 10.56 km/s.
Comet 252P/LINEAR orbit diagram: Credit: NASA/JPL CNEOS
Comet P/2016 BA14 is traveling at a speed of 14.01 km/s and will safely fly by our planet at 15:31 UTC on March 22 at a distance of about 3.5 million km (9.2 LD / 2.2 million miles). This will be the third closest flyby of a comet in recorded history next to comet D/1770 L1 (Lexell) in 1770 and comet C/1983 H1 (IRAS-Araki-Alcock) in 1983.
Comet P/2016 BA14 (PANSTARRS) orbit diagram: Credit: NASA/JPL CNEOS
While both comets will safely fly past at relatively close distances, anyone hoping to see them will need powerful, professional-grade telescopes, due to their relatively small size.
The approaches of these two comets will be the closest they come to Earth for the foreseeable future.
“March 22 will be the closest comet P/2016 BA14 gets to us for at least the next 150 years,” said Chodas. “Comet P/2016 BA14 is not a threat. Instead, it is an excellent opportunity for scientific advancement on the study of comets.”
