see § List of numbered minor planets discovered by OSSOS |
The Outer Solar System Origins Survey (OSSOS) is an astronomical survey and observing program aimed at discovering and tracking trans-Neptunian objects located in the outermost regions of the Solar System beyond the orbit of Neptune. OSSOS is designed in way that observational biases can be characterized, allowing the numbers and orbits of detected objects to be compared using a survey simulator to the populations predicted in dynamical simulations of the emplacement of trans-Neptunian objects. [2] Conducted at the Canada-France-Hawaii telescope at Mauna Kea Observatories ( 568 ) in Hawaii, the survey has discovered 39 numbered objects as of 2018, [1] with potentially hundreds more to follow. The survey's first numbered discovery was the object (496315) 2013 GP136 in 2013.
OSSOS observed eight blocks of the sky over a period of five years from 2013–2017 using the MegaPrime camera of the 3.6-meter Canada-France-Hawaii Telescope. Images of these blocks were taken near opposition (when the block is near opposite the sun), two months before, and two months after. [3] This extended period of observation was designed to remove ephemeris bias which can cause the loss of some objects due to inaccurate predictions of their future positions. Pointing directions, detection efficiencies, and tracking frequencies were determined to allow other observational biases to be identified. [4]
These identified biases are used by the survey simulator developed by the OSSOS group. This survey simulator can estimate the populations of detected objects, for example those in resonances, and set upper limits for the classes of objects not detected. The survey simulator can also predict the number of object that would be detected by OSSOS given the output of dynamical models of the early Solar System, allowing the models to be statistically tested. [5]
OSSOS has detected 838 objects, bring the total objects detected by well characterized surveys to more than 1100. [6] [7] Among these objects are a possible dwarf planet in a 9:2 resonance with Neptune, [8] and two objects in a 9:1 resonance with Neptune. [9] Other resonant objects have been detected and their populations estimated. [10] A previously identified 'kernel' in the cold classical Kuiper belt has been confirmed and other cold classical objects beyond the 2:1 resonance with Neptune have been identified. [4] OSSOS detected 3 potential members of the Haumea family, but none of these were faint, indicating that the family has a shallow size distribution. [11] Analysis of the size distribution of the scattering population revealed a break in its slope. [3] [12] The inclination distribution of these scattering objects had more with inclinations greater than 45 degrees than predicted using simulations that included only the known planets and the influence of the galaxy, but also fewer with inclinations between 15 and 30 degrees than predicted when Planet Nine was added to the simulations. [13] Extreme trans-Neptunian objects (eTNOs) have been found including one with a semi-major axis of 730 AU, 2013 SY99, [14] and seven other objects with semi-major axes greater than 150 AU and perihelia greater than 30 AU. After accounting for OSSOS's known biases the orbital elements of these objects are consist with a uniformly distributed population. [15] Four scattered disk objects with high perihelia have been detected with semi-major axes smaller than nearby resonances, consistent with their escape during a slow grainy migration of Neptune. [16] Closer to the Sun, 20 centaurs were found, none of which were active. [17] The number of centaurs detected and their inclinantion distribution were consistent with a model of the early Solar System that included a slow, long range migration of Neptune. [18] 65 of the smaller objects discovered by OSSOS were later observed using the Subaru telescope to determine the variability of their brightness. [19]
Operating in conjunction with OSSOS is the Colours of the Outer Solar System Origins Survey (Col-OSSOS). Col-OSSOS observes OSSOS objects with red magnitudes brighter than 23.5 simultaneously using the Gemini-North and Canada-France-Hawaii telescopes. [20] The simultaneous observation allows the colors of these object to be measured more accurately by removing variations in their brightness due to the rotation of the objects and changes in atmospheric conditions. These observations have revealed three surface types among the TNOs, [21] and have identified numerous binaries including loosely bound neutrally colored 'blue binaries' that could have been pushed out into their current orbits during Neptune's migration. [22] Among the dynamically excited populations the ratio of neutral to red objects has been estimated to be between 4:1 and 11:1. [23] The inclination distributions were found to vary with color, with the red objects having lower inclinations. [24] The Col-OSSOS team has also measured the color and light curve of ʻOumuamua. [25]
The core members of the Outer Solar System Origin Survey are: [26]
Collaborators of the Outer Solar System Origin Survey are: [26]
Name | Date | List |
---|---|---|
(496315) 2013 GP136 | 2013/02/08 | list |
(500828) 2013 GR136 | 2013/04/04 | list |
(500829) 2013 GT136 | 2013/04/04 | list |
(500830) 2013 GU136 | 2013/04/04 | list |
(500831) 2013 GV136 | 2013/04/09 | list |
(500832) 2013 GZ136 | 2013/04/04 | list |
(500833) 2013 GD137 | 2013/04/04 | list |
(500834) 2013 GK137 | 2013/04/09 | list |
(500835) 2013 GN137 | 2013/04/04 | list |
(500836) 2013 GQ137 | 2013/04/04 | list |
(500837) 2013 GT137 | 2013/04/09 | list |
(500838) 2013 GV137 | 2013/04/09 | list |
(500839) 2013 GW137 | 2013/04/09 | list |
(500840) 2013 GA138 | 2013/04/09 | list |
(500856) 2013 HT156 | 2013/04/09 | list |
(500876) 2013 JD64 | 2013/05/08 | list |
(500877) 2013 JE64 | 2013/05/07 | list |
(500878) 2013 JG64 | 2013/05/07 | list |
(500879) 2013 JH64 | 2013/05/07 | list |
(500880) 2013 JJ64 | 2013/05/07 | list |
(500881) 2013 JM64 | 2013/05/08 | list |
(500882) 2013 JN64 | 2013/05/08 | list |
(500883) 2013 JJ65 | 2013/05/08 | list |
(500884) 2013 JK65 | 2013/05/08 | list |
(500885) 2013 JL65 | 2013/05/08 | list |
(500886) 2013 JN65 | 2013/05/07 | list |
(500887) 2013 JO65 | 2013/05/07 | list |
(500888) 2013 JP65 | 2013/05/07 | list |
(505446) 2013 SP99 | 2013/08/05 | list |
(505447) 2013 SQ99 | 2013/08/05 | list |
(505448) 2013 SA100 | 2013/08/05 | list |
(505476) 2013 UL15 | 2013/08/02 | list |
(505477) 2013 UM15 | 2013/08/02 | list |
(505478) 2013 UT15 | 2013/08/02 | list |
(511551) 2014 UD225 | 2013/08/08 | list |
(511552) 2014 UE225 | 2013/08/08 | list |
(511553) 2014 UK225 | 2013/11/29 | list |
(511554) 2014 UL225 | 2013/09/01 | list |
(511555) 2014 UM225 | 2013/08/08 | list |
Caliban is the second-largest retrograde irregular satellite of Uranus. It was discovered on 6 September 1997 by Brett J. Gladman, Philip D. Nicholson, Joseph A. Burns, and John J. Kavelaars using the 200-inch Hale Telescope together with Sycorax and given the temporary designation S/1997 U 1.
Neso, also known as Neptune XIII, is the second-outermost known natural satellite of Neptune, after S/2021 N 1. It is a retrograde irregular moon discovered by Matthew J. Holman, Brett J. Gladman, et al. on 14 August 2002, though it went unnoticed until 2003. Neso is the second-most distant moon of Neptune, with an average orbital distance of nearly 49.6 million km. At its farthest point of its orbit, the satellite is more than 72 million km from Neptune. This distance exceeds Mercury's aphelion, which is approximately 70 million km from the Sun.
The scattered disc (or scattered disk) is a distant circumstellar disc in the Solar System that is sparsely populated by icy small Solar System bodies, which are a subset of the broader family of trans-Neptunian objects. The scattered-disc objects (SDOs) have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°, and perihelia greater than 30 astronomical units (4.5×109 km; 2.8×109 mi). These extreme orbits are thought to be the result of gravitational "scattering" by the gas giants, and the objects continue to be subject to perturbation by the planet Neptune.
Detached objects are a dynamical class of minor planets in the outer reaches of the Solar System and belong to the broader family of trans-Neptunian objects (TNOs). These objects have orbits whose points of closest approach to the Sun (perihelion) are sufficiently distant from the gravitational influence of Neptune that they are only moderately affected by Neptune and the other known planets: This makes them appear to be "detached" from the rest of the Solar System, except for their attraction to the Sun.
A sednoid is a trans-Neptunian object with a large semi-major axis and a high perihelion, similar to the orbit of the dwarf planet Sedna. The consensus among astronomers is that there are only three objects that are known from this population: Sedna, 2012 VP113, and 541132 Leleākūhonua (2015 TG387). All three have perihelia greater than 60 AU. These objects lie outside an apparently nearly empty gap in the Solar System and have no significant interaction with the planets. They are usually grouped with the detached objects. Some astronomers consider the sednoids to be Inner Oort Cloud (IOC) objects, though the inner Oort cloud, or Hills cloud, was originally predicted to lie beyond 2,000 AU, beyond the aphelia of the three known sednoids.
An extreme trans-Neptunian object (ETNO) is a trans-Neptunian object orbiting the Sun well beyond Neptune (30 AU) in the outermost region of the Solar System. An ETNO has a large semi-major axis of at least 150–250 AU. The orbits of ETNOs are much less affected by the known giant planets than all other known trans-Neptunian objects. They may, however, be influenced by gravitational interactions with a hypothetical Planet Nine, shepherding these objects into similar types of orbits. The known ETNOs exhibit a highly statistically significant asymmetry between the distributions of object pairs with small ascending and descending nodal distances that might be indicative of a response to external perturbations.
Planet Nine is a hypothetical ninth planet in the outer region of the Solar System. Its gravitational effects could explain the peculiar clustering of orbits for a group of extreme trans-Neptunian objects (ETNOs), bodies beyond Neptune that orbit the Sun at distances averaging more than 250 times that of the Earth i.e. over 250 astronomical units (AU). These ETNOs tend to make their closest approaches to the Sun in one sector, and their orbits are similarly tilted. These alignments suggest that an undiscovered planet may be shepherding the orbits of the most distant known Solar System objects. Nonetheless, some astronomers question this conclusion and instead assert that the clustering of the ETNOs' orbits is due to observational biases, resulting from the difficulty of discovering and tracking these objects during much of the year.
2013 GP136 is a trans-Neptunian object from the scattered disc in the outermost reaches of the Solar System, approximately 212 kilometers in diameter. It was discovered on 8 February 2013, by the Outer Solar System Origins Survey at the Mauna Kea Observatories on the island of Hawaii, United States.
2013 SY99, also known by its OSSOS survey designation uo3L91, is a trans-Neptunian object discovered on September 29, 2013 by the Outer Solar System Origins Survey using the Canada–France–Hawaii Telescope at Mauna Kea Observatory. This object orbits the Sun between 50 and 1,300 AU (7.5 and 190 billion km), and has a barycentric orbital period of nearly 20,000 years. It has the fourth largest semi-major axis for an orbit with perihelion beyond 38 AU. 2013 SY99 has one of highest perihelia of any known extreme trans-Neptunian object, behind sednoids including Sedna (76 AU), 2012 VP113 (80 AU), and Leleākūhonua (65 AU).
(523794) 2015 RR245, provisional designation 2015 RR245, is a large trans-Neptunian object of the Kuiper belt in the outermost regions of the Solar System. It was discovered on 9 September 2015, by the Outer Solar System Origins Survey at Mauna Kea Observatories on the Big island of Hawaii, in the United States. The object is in a rare 2:9 resonance with Neptune and measures approximately 600 kilometers in diameter. 2015 RR245 was suspected to have a satellite according to a study announced by Noyelles et al. in a European Planetary Science Congress meeting in 2019.
2015 GT50, previously known as o5p060, is a trans-Neptunian object orbiting in the Kuiper belt of the outermost Solar System. It was first observed by the Outer Solar System Origins Survey using the Canada–France–Hawaii Telescope at Mauna Kea on 13 April 2015.
2015 RY245, also known as o5s13, is a trans-Neptunian object from the scattered disc of the outermost reaches of the Solar System, approximately 78 kilometers in diameter. It was discovered on 9 September 2015, by the Outer Solar System Origins Survey using the Canada–France–Hawaii Telescope at Mauna Kea Observatories, Hawaii, United States.
2015 KE172, internal designation o5m72, is a distant resonant trans-Neptunian object on an eccentric orbit in the outermost region of the Solar System, approximately 100 kilometers (60 miles) in diameter. It was first observed on 21 May 2015 by astronomers with the Outer Solar System Origins Survey at the Mauna Kea Observatories on the island of Hawaii, United States. It came to perihelion (closest approach to the Sun) in October 2017 at a distance of 44.1 AU (6.60 billion km). Its existence was first released in February 2018, and the observations and orbit were announced on 27 April 2018. It belongs to the most distant resonant objects known to exist.
Michele Bannister is a New Zealand planetary astronomer and science communicator at the University of Canterbury, who has participated in surveying the outermost Solar System for trans-Neptunian objects.
(505448) 2013 SA100, provisional designation 2013 SA100 and also known as o3l79, is a trans-Neptunian object from the classical Kuiper belt in the outermost region of the Solar System. It was discovered on 5 August 2013, by astronomer with the Outer Solar System Origins Survey at the Mauna Kea Observatories, Hawaii, in the United States. The classical Kuiper belt object belongs to the hot population and is a weak dwarf planet candidate, approximately 260 kilometers (160 miles) in diameter.
The hypothetical Planet Nine would modify the orbits of extreme trans-Neptunian objects via a combination of effects. On very long timescales exchanges of angular momentum with Planet Nine cause the perihelia of anti-aligned objects to rise until their precession reverses direction, maintaining their anti-alignment, and later fall, returning them to their original orbits. On shorter timescales mean-motion resonances with Planet Nine provides phase protection, which stabilizes their orbits by slightly altering the objects' semi-major axes, keeping their orbits synchronized with Planet Nine's and preventing close approaches. The inclination of Planet Nine's orbit weakens this protection, resulting in a chaotic variation of semi-major axes as objects hop between resonances. The orbital poles of the objects circle that of the Solar System's Laplace plane, which at large semi-major axes is warped toward the plane of Planet Nine's orbit, causing their poles to be clustered toward one side.
2013 VZ70 is a centaur on a horseshoe co-orbital configuration with Saturn. It was first observed on 1 November 2013 by the Outer Solar System Origins Survey at Mauna Kea Observatory in Hawaii, United States. The discovery was announced on 23 August 2021.
2021 RR205 is an extreme trans-Neptunian object discovered by astronomers Scott Sheppard, David Tholen, and Chad Trujillo with the Subaru Telescope at Mauna Kea Observatory on 5 September 2021. It resides beyond the outer extent of the Kuiper belt on a distant and highly eccentric orbit detached from Neptune's gravitational influence, with a large perihelion distance of 55.5 astronomical units (AU). Its large orbital semi-major axis (~1,000 AU) suggests it is potentially from the inner Oort cloud. 2021 RR205 and 2013 SY99 both lie in the 50–75 AU perihelion gap that separates the detached objects from the more distant sednoids; dynamical studies indicate that such objects in the inner edge this gap weakly experience "diffusion", or inward orbital migration due to minuscule perturbations by Neptune. While Sheppard considers 2021 RR205 a sednoid, researchers Yukun Huang and Brett Gladman do not.