User:Renerpho/sandbox/V774104

Well, given that most sources on the object are incorrect, and that we need to cite a source for the correct info or it is WP:OR, there's not much we can do. This is the article from hell. It shouldn't exist, but it exists, and the majority of the sources are wrong. Feel free to edit it to give your thoughts on the issue. ― Дрейгорич / Dreigorich Talk 06:53, 11 July 2019 (UTC)

V774104

Discovery
Discovery site	Subaru Telescope
Discovery date	13 October 2015
Designations
Minor planet category	sednoid?
Orbital characteristics
Observation arc	~2 weeks as of 2015 announcement
Perihelion	>50 AU?
Semi-major axis	>150 AU?
Physical characteristics
Dimensions	500–1000 km
Apparent magnitude	~24
Absolute magnitude (H)	~4

V774104 is a trans-Neptunian object (TNO) with a radius roughly half that of Pluto or somewhat smaller. When the discovery was announced in November 2015, based on a short observation arc of 2 weeks, it was believed to be approximately 103 AU from the Sun, a distance of 15.4 billion kilometers (9.6 billion miles). This would have made it the most distant observed natural object in the Solar System.

MPC designation

The 2015 press coverage for V774104 may have been mistaken with V302126 (now sednoid 2015 TG387) as V302126 was the short-arc object that appeared to be around 100 AU from the Sun. V774104 is the internal designation for 2015 TH367. The object is likely meant to represent 2015 TG387 (the discovery images seem identical), but due to an error in the announcement by mixing up objects with similar designations, it was announced as corresponding to 2015 TH367 instead.

However, Scott Sheppard denies any mix-up, saying that V774104 was meant to be 2015 TH367 all along, and that the idea that it is 2015 TG387 is an erroneous interpretation that the media announced.

Discovery

The object's discovery telescope, Subaru (Japanese name for the Pleiades) on the far left, alongside the twin Keck telescopes and NASA's Infrared Telescope Facility

V774104 was discovered by Scott S. Sheppard, Chad Trujillo, and David J. Tholen using the Subaru Telescope, a large reflecting telescope at the summit of Mauna Kea with a primary mirror 8 meters (26 ft) in diameter. It was discovered in the direction of west-central Pisces. The discovery was announced at the November 2015 meeting of the American Astronomical Society's Division for Planetary Sciences. 2015 TG387, 2015 TH367, and 2015 TJ₃₆₇ were also discovered by this team on 13 October 2015.

Orbit

No astrometry has been released publicly so the object does not have a minor planet designation and the uncertainties of the orbital elements are unknown. Being a trans-Neptunian object so far from the Sun with an observation arc of just a few weeks at the time of its discovery announcement, its perihelion and aphelion have not been precisely measured.

Possible sednoid

The orbit of Sedna (in red), the prototypical sednoid, set against the orbits of Pluto (purple) and the outer planets

V774104 appears to be a sednoid, an enigmatic class of objects in the outer Solar System with only two known members. Sednoids have eccentric orbits that must have been perturbed by something, but could not have been perturbed by any presently known body (their entire orbits lie well outside the influence of Neptune). To be a sednoid, V774104 must have a perihelion greater than 50 AU and a semi-major axis greater than 150 AU, which can be determined when its observation arc is around one year. In 2015, only 3 published objects were known to have perihelia (closest approach to the Sun) greater than 50 AU: 90377 Sedna, 2012 VP113, and 2004 XR190. But 2004 XR₁₉₀ has a low orbital eccentricity with perihelion at 51 AU. In 2014 and 2015, three further bodies similar to 2004 XR₁₉₀ were discovered with perihelion between 50 and 56 AU. Sedna and 2012 VP₁₁₃ have both had their perihelion point lifted well beyond the classic Kuiper belt of 30–50 AU. If V774104 is confirmed to be a sednoid or extreme trans-Neptunian object, it may point towards an undiscovered shepherding planet hundreds of astronomical units from the Sun. It is also possible, however, that the lifted perihelion was a result of the crowded confines of the open star cluster in which the Sun formed. Discovery of additional sednoids and analysis of their orbits should eventually permit identification of the process by which their orbits were disturbed.

Most distant Solar System object

See also: List of most distant trans-Neptunian objects

Many news sources heralded V774104 as "the most distant Solar System object". In fact, various long-period and hyperbolic comets are more distant, though all of these are much smaller bodies and not observable at such distances. Since the time of its discovery, the Voyager (Voyager 1, Voyager 2) and Pioneer 10 spacecraft have also been more distant; the Voyager probes are observable via their artificial radio transmissions.

Observed Solar System objects that periodically become more distant than 103 AU from the Sun include Sedna (which is similar or modestly larger in size), 2000 CR105, 2012 DR30, 2013 BL76, and 2005 VX3. There are 726 known objects that have aphelia more than 103 AU from the Sun. This distance is about double the outer limit of the torus-shaped Kuiper belt that lies outside Neptune's orbit. Far beyond this region is the vast spherical Oort cloud enshrouding the Solar System, whose presence was deduced from the orbits of long-period comets.

Study of the population of Solar System objects that are significantly more distant than V774104 will likely require new instruments. The proposed Whipple spacecraft mission is designed to determine the outer limit of the Kuiper belt and directly detect Oort cloud objects out to 10,000 AU. Such objects are too small to detect with current telescopes except during stellar occultations. The proposal involves use of a wide field of view and rapid recording cadence to allow detection of many such events.

See also

• Discovery and exploration of the Solar System
• List of Solar System objects most distant from the Sun in 2015
• U (TNO)