Also Known as: Comet 64/Swift-Gehrels 2018
Object Type: Periodic comet
Comet Background: A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing.
This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, and sometimes a tail of gas and dust gas blown out from the coma.
These phenomena are due to the effects of solar radiation and the outstreaming solar wind plasma acting upon the nucleus of the comet.
Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles.
The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit.
If sufficiently close and bright, a comet may be seen from Earth without the aid of a telescope and can subtend an arc of up to 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religions.
Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several millions of years.
Short-period comets originate in the Kuiper belt or its associated scattered disc, which lie beyond the orbit of Neptune.
Long-period comets are thought to originate in the Oort cloud, a spherical cloud of icy bodies extending from outside the Kuiper belt to halfway to the nearest star.
Long-period comets are set in motion towards the Sun by gravitational perturbations from passing stars and the galactic tide.
Hyperbolic comets may pass once through the inner Solar System before being flung to interstellar space.
The appearance of a comet is called an apparition.
Discovered by: It was originally discovered on 17 November 1889 by Lewis A. Swift at the Warner Observatory, Rochester, New York, and was described by Swift as being pretty faint.
It was rediscovered on 8 February 1973 by Tom Gehrels at the Palomar Observatory, California who estimated its brightness as a very low magnitude 19.
Description: 64P/Swift–Gehrels is a periodic comet in the Solar System which has a current orbital period of 9.23 years.
64P/Swift-Gehrels is a mid-sized comet whose orbit features a relatively short period, low inclination, and is controlled by Jupiter's gravitational effects.
NASA JPL has not classified 64P/Swift-Gehrels as potentially hazardous because its orbit does not bring it close to Earth.64P/Swift-Gehrels orbits the sun every 3,440 days (9.42 years), coming as close as 1.39 AU and reaching as far as 7.52 AU from the sun.
64P/Swift-Gehrels is about 3.2 kilometers in diameter, making it larger than 99% of asteroids, comparable in size to the island of Manhattan.
It was also observed in 1981, 1991, 2000, 2009 and 2018. The 2018 apparition was the most favorable, with the comet reaching a peak magnitude of 9.
It had its closest approach to the Earth on 28 October 2018, at a distance of 0.445 AU. The comet had four outbursts.
The brightest was on August 14, during which the comet brightened 2.7 magnitudes.
64P/Swift-Gehrels's orbit is 0.44 AU from Earth's orbit at its closest point. This means that there is a wide berth between this asteroid and Earth at all times.
Orbital simulations conducted by NASA JPL's CNEOS do not show any close approaches to Earth.
Date: December 4 and December 10, 2018
Equipment used: Celestron 11 inch Schmidt Cassegrain telescope and ZWO ASI 071 camera with 0.7 focal reducer.
Camera Settings: ZWO ASI 071 set for HDR gain, 60 second exposures, with camera at -20 deg C, and binned 1x1.
Frames and Processing Took 40 images.
Then use Photoshop to crop, center, and adjust the levels. Used Cyberlink PowerDirector 15 to generate the time lapse video.
Comet 64/Swift-Gehrels 2018