(Catalina) is an

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 ...

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 31 October 2013 by the

Catalina Sky Survey Catalina Sky Survey (CSS; obs. code: 703) is an astronomical survey to discover comets and asteroids. It is conducted at the Steward Observatory's Catalina Station, located near Tucson, Arizona, in the United States. CSS focuses on the search ...

at an

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 ...

of 19 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 ...

. the comet is around

Overview

When discovered on 31 October 2013 observations from another object from 12 September 2013 were used in the preliminary

orbit determination Orbit determination is the estimation of orbits of objects such as moons, planets, and spacecraft. One major application is to allow tracking newly observed asteroids and verify that they have not been previously discovered. The basic methods wer ...

giving an incorrect solution that suggested an

orbital period The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets ...

of only 6 years. But by 6 November 2013 a longer

observation arc In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...

from 14 August until 4 November made it apparent that the first solution had the wrong object from 12 September. By early May 2015 the comet was around

12 and had an elongation of 60 degrees from the Sun as it moved further into the southern hemisphere. The comet came to

solar conjunction Solar conjunction generally occurs when a planet or other Solar System object is on the opposite side of the Sun from the Earth. From an Earth reference, the Sun will pass between the Earth and the object. Communication with any spacecraft in sol ...

on 6 November 2015 when the comet was around magnitude 6. 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 15 November 2015 at a distance of 0.82 AU from the Sun. At perihelion, it had a velocity of with respect to the Sun which is slightly greater than the Sun's escape velocity at that distance. 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 17 December 2015 becoming a northern hemisphere object. On 17 January 2016 the comet will pass from Earth and should be around magnitude 6 while located in the constellation of

Ursa Major Ursa Major (; also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) bear," referring to and contrasting it with nearby Ursa ...

. is dynamically new. It came from the

with a loosely bound chaotic orbit that was easily perturbed by

galactic tide A galactic tide is a tidal force experienced by objects subject to the gravitational field of a galaxy such as the Milky Way. Particular areas of interest concerning galactic tides include galactic collisions, the disruption of dwarf or satelli ...

s and passing stars. 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 several million years. After leaving the planetary region (epoch 2050), it will be on an ejection trajectory.

Gallery

File:Comet C-2013 US10-Warsaw.jpg, Comet (Warsaw, Poland; 10 January 2016, 02:51 UT+1) File:C2013US10 CATALINA 06DEC2015 J87.jpg, imaged on 6 December 2015 File:C2013 US10 06DEC2015 J87 BW.jpg, imaged on 6 December 2015 (black and white)

References

External links

C/2013 US10 (Catalina) at CometBase

Forbes - Comet Catalina To Pass By Earth For The Final Time
* {{2014 in space 20131031 20151115 Oort cloud