C/2014 Q2 (Lovejoy) is a long-period

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ...

discovered on 17 August 2014 by Terry Lovejoy using a

Schmidt–Cassegrain telescope The Schmidt–Cassegrain is a catadioptric telescope that combines a Cassegrain reflector's optical path with a Schmidt corrector plate to make a compact astronomical instrument that uses simple spherical surfaces. Invention and design The A ...

. It was discovered at

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's ...

15 in the southern constellation of Puppis. It is the fifth comet discovered by Terry Lovejoy. Its blue-green glow is the result of organic molecules (mostly

Diatomic carbon Diatomic carbon (systematically named dicarbon and 1λ2,2λ2-ethene), is a green, gaseous inorganic chemical with the chemical formula C=C (also written 2or C2). It is kinetically unstable at ambient temperature and pressure, being removed thro ...

) and water released by the comet fluorescing under the intense UV and optical light of the Sun as it passes through space.

History

By December 2014, the comet had brightened to roughly magnitude 7.4, making it a small telescope and binoculars target. By mid-December, the comet was visible to the

naked eye Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying, light-collecting optical instrument, such as a telescope or microscope, or eye protection. Vision corrected to normal ...

for experienced observers with dark skies and keen eyesight. On 28–29 December 2014, the comet passed 1/3° from

globular cluster A globular cluster is a spheroidal conglomeration of stars. Globular clusters are bound together by gravity, with a higher concentration of stars towards their centers. They can contain anywhere from tens of thousands to many millions of membe ...

Messier 79 Messier 79 (also known as M79 or NGC 1904) is a globular cluster in the southern Lepus constellation, constellation Lepus. It was discovered by Pierre Méchain in 1780 and is about 42,000 light-years away from Earth and 60,000 light years from t ...

. In January 2015, it brightened to roughly magnitude 4, and became one of the brightest comets located high in a dark sky since comet ( Hale-Bopp) in 1997. On 7 January 2015, the comet passed from Earth. It crossed the

celestial equator The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth. This plane of reference bases the equatorial coordinate system. In other words, the celestial equator is an abstract proj ...

on 9 January 2015, becoming better seen from the Northern Hemisphere. The comet came to

perihelion An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any elli ...

(closest approach to the Sun) on 30 January 2015, at a distance of from the Sun. At perihelion, its water production rate exceeded 20 metric tons per second. C/2014 Q2 originated from the

Oort cloud The Oort cloud (), sometimes called the Öpik–Oort cloud, first described in 1950 by the Dutch astronomer Jan Oort, is a theoretical concept of a cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from ...

, but is not a dynamically new comet. Before entering the planetary region (

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

1950), had an orbital period of about 11,000 years, with an aphelion about from the Sun. After leaving the planetary region (epoch 2050), it will have an orbital period of about 8,000 years, with aphelion of about 800 AU. The comet was observed to release 21 different

organic molecule In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Th ...

s in gas, including

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...

and

glycolaldehyde Glycolaldehyde is the organic compound with the formula . It is the smallest possible molecule that contains both an aldehyde group () and a hydroxyl group (). It is a highly reactive molecule that occurs both in the biosphere and in the inters ...

, a simple sugar. The presence of organic molecules suggests that they are preserved materials synthesized in the outskirts of the solar nebula or at earlier stages of the Solar System formation.

Gallery

File:Celestial Nomad Takes Centre Stage.jpg, C/2014 Q2 glowing green over

La Silla Observatory La Silla Observatory is an astronomical observatory in Chile with three telescopes built and operated by the European Southern Observatory (ESO). Several other telescopes are located at the site and are partly maintained by ESO. The observatory is ...

File:Comet - 2014 Q2 - Lovejoy.jpg, C/2014 Q2 seen passing through

Lepus Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called forms, and their young are able to fend for themselves shortly after birth. The gen ...

, 29 December 2014 File:2015-01-17 Comet C2014 Q2 Lovejoy 4x60sec f10 2000mm ISO2500.jpg, C/2014 Q2, 17 January 2015, with an 8"

File:Comet lovejoy and the Pleiades.jpg, C/2014 Q2 and the Pleiades star cluster, 19 January 2015, with a

DSLR A digital single-lens reflex camera (digital SLR or DSLR) is a digital camera that combines the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor. The reflex design scheme is the primary difference between a ...

File:PIA19354-CometLovejoy-20150130.jpg, C/2014 Q2, 30 January 2015,

NEOWISE Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 201 ...

References

External links

Two possible light curves
(Alexandre Amorim)

(Damian Peach)
C/2014 Q2 (Lovejoy) at CometBase database
{{DEFAULTSORT:Lovejoy, 2014 Q2 20140817 2014Q02 20150107 20140817 20150130