1998 WW31

Last updated

1998 WW31
2000 (1998 WW31) 1.jpg
Hubble Space Telescope image of 1998 WW31 and its satellite in orbit
Discovery [1]
Discovered by M. W. Buie [2]
R. L. Millis [3]
Discovery site Kitt Peak Obs.
Discovery date18 November 1998
(first observed only)
Designations
1998 WW31
TNO [2] [4]  · cubewano (hot) [5]
distant [1]  · binary [6]
Orbital characteristics [4]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 4
Observation arc 20.94 yr (7,647 d)
Aphelion 48.526 AU
Perihelion 40.429 AU
44.477 AU
Eccentricity 0.09102
296.63 yr (108,345 d)
141.847°
0° 0m 11.963s / day
Inclination 6.8171°
237.138°
51.218°
Known satellites 1 (D: 123  km ; P: 587 d) [6] [7]
Physical characteristics
148  km (est. primary) [5] [6]
192.1 km(cal. system) [8]
Mass (2.658±0.015)×1018 kg [9]
0.04 (est.) [10]
0.10(assumed) [8]
blue [10]
C (assumed) [8]
V–I = 0.910±0.020 [11]
6.7 [4] [8]
6.9 [10]

    1998 WW31, is a non-resonant trans-Neptunian object and binary system from the Kuiper belt located in the outermost region of the Solar System, approximately 148 kilometers (92 miles) in diameter. It was first observed on 18 November 1998, by American astronomer Marc Buie and Robert Millis at the Kitt Peak National Observatory in Arizona, United States. [2] [3] [1] In December 2000, a minor-planet moon, designated S/2000 (1998 WW31) 1 with a diameter of 123 kilometers (76 miles), was discovered in its orbit. [7] After Charon in 1978, it was the first of nearly 100 satellites since discovered in the outer Solar System. [3] [7]

    Contents

    Orbit and classification

    Located beyond the orbit of Neptune, 1998 WW31 is a non-resonant classical Kuiper belt object (cubewano) of the so-called hot population, which have higher inclinations than those of the cold population. [5] [12] It orbits the Sun at a distance of 40.4–48.5  AU once every 297 years (108,345 days; semi-major axis of 44.48 AU). Its orbit has an eccentricity of 0.09 and an inclination of 7° with respect to the ecliptic. [4] The body's observation arc begins at Kitt Peak with its first observation on 18 November 1998. [1]

    Numbering and naming

    As of 2018, this minor planet has not been numbered nor named by the Minor Planet Center. [1]

    Physical characteristics

    1998 WW31 is expected to have a low albedo due to its blue (neutral) color. [10] Other sources assume a higher albedo of 0.10 and 0.16, respectively (see below). [6] [8] It has a V–I color index of 0.91, [11] notably lower than the mean-color index for cubewanos, and in between that of comets and Jupiter trojans. [13] : 35 

    Hubble image composite from 2001 to 2002 of 1998 WW31 with its satellite on a long, 587-day orbit Kuiper Belt Object 1998 WW31.jpg
    Hubble image composite from 2001 to 2002 of 1998 WW31 with its satellite on a long, 587-day orbit

    Satellite

    1998 WW31 is a binary minor planet with a minor-planet moon in its orbit. On 22 December 2000, French astronomers Christian Veillet and Alain Doressoundiram in collaboration with J. Shapiro discovered the satellite using the Canada–France–Hawaii Telescope at Mauna Kea on the Big Island of Hawaii, United States. The discovery was announced on 16 April 2001 and received the provisional designation S/2000 (1998 WW31) 1. [7]

    It was the first trans-Neptunian binary discovered after Charon in 1978, the largest satellite in the Pluto–Charon system. [3] Since then nearly 100 trans-Neptunian binaries have been discovered. 1998 WW31 is also one of the most symmetrical binaries known in the Solar System.

    The satellite has a highly eccentric orbit with eccentricity of 0.8193±0.0020 with an exceptionally long orbital period of 587.27±0.18 d and a semi-major axis of 22617±42 km. [9]

    Diameter and albedo

    While the primary measures 148 kilometres (92 mi), the satellite has a diameter of 123 kilometres (76 mi) (a ratio of 0.883) with a combined system diameter of 192 kilometres (119 mi). [6] [12] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 and calculates a system diameter of 192 kilometres (119 mi) based on an absolute magnitude of 6.7, [8] while Mike Brown finds a diameter of 267 kilometres (166 mi) with a lower albedo of 0.04. [10]

    Rotation period

    As of 2020, no rotational lightcurve of 1998 WW31 has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown. [8] [12]

    Related Research Articles

    A trans-Neptunian object (TNO), also written transneptunian object, is any minor planet in the Solar System that orbits the Sun at a greater average distance than Neptune, which has an orbital semi-major axis of 30.1 astronomical units (AU).

    5145 Pholus is an eccentric centaur in the outer Solar System, approximately 180 kilometers in diameter, that crosses the orbit of both Saturn and Neptune. It was discovered on 9 January 1992 by American astronomer David Rabinowitz (uncredited) of UA's Spacewatch survey at the Kitt Peak National Observatory in Arizona, United States. The very reddish object has an elongated shape and a rotation period of 9.98 hours. It was named after the centaur Pholus from Greek mythology.

    <span class="mw-page-title-main">Minor-planet moon</span> Natural satellite of a minor planet

    A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite. As of January 2022, there are 457 minor planets known or suspected to have moons. Discoveries of minor-planet moons are important because the determination of their orbits provides estimates on the mass and density of the primary, allowing insights into their physical properties that are generally not otherwise accessible.

    <span class="mw-page-title-main">28978 Ixion</span> Plutino

    28978 Ixion (, provisional designation 2001 KX76) is a large trans-Neptunian object and a possible dwarf planet. It is located in the Kuiper belt, a region of icy objects orbiting beyond Neptune in the outer Solar System. Ixion is classified as a plutino, a dynamical class of objects in a 2:3 orbital resonance with Neptune. It was discovered in May 2001 by astronomers of the Deep Ecliptic Survey at the Cerro Tololo Inter-American Observatory, and was announced in July 2001. The object is named after the Greek mythological figure Ixion, who was a king of the Lapiths.

    <span class="mw-page-title-main">19521 Chaos</span> Classical Kuiper belt object

    19521 Chaos is a cubewano, a Kuiper-belt object not in resonance with any planet. Chaos was discovered in 1998 by the Deep Ecliptic Survey with Kitt Peak's 4 m telescope. Its albedo is 0.050+0.030
    −0.016    , making it, with its absolute magnitude (H) of 4.8, equivalent to a single spherical body 600+140
    −130     km     in diameter.

    <span class="mw-page-title-main">38628 Huya</span> Trans-Neptunian object

    38628 Huya ( hoo-YAH; provisional designation 2000 EB173) is a binary trans-Neptunian object located in the Kuiper belt, a region of icy objects orbiting beyond Neptune in the outer Solar System. Huya is classified as a plutino, a dynamical class of trans-Neptunian objects with orbits in a 3:2 orbital resonance with Neptune. It was discovered by the Quasar Equatorial Survey Team and was identified by Venezuelan astronomer Ignacio Ferrín in March 2000. It is named after Juyá, the mythological rain god of the Wayuu people native to South America.

    <span class="mw-page-title-main">47171 Lempo</span> System comprising three trans-Neptunian objects

    47171 Lempo, or as a binary (47171) Lempo–Hiisi (provisional designation 1999 TC36), is a trans-Neptunian object and trinary system from the Kuiper belt, located in the outermost regions of the Solar System. It was discovered on 1 October 1999, by American astronomers Eric Rubenstein and Louis-Gregory Strolger during an observing run at Kitt Peak National Observatory in Arizona, United States. Rubenstein was searching images taken by Strolger as part of their Nearby Galaxies Supernova Search project. It is classified as a plutino with a 2:3 mean-motion resonance with Neptune and is among the brighter TNOs. It reached perihelion in July 2015. This minor planet was named after Lempo from Finnish mythology.

    <span class="nowrap">(55565) 2002 AW<sub>197</sub></span> Classical Kuiper belt object

    (55565) 2002 AW197 (provisional designation 2002 AW197) is a classical, non-resonant trans-Neptunian object from the Kuiper belt in the outermost region of the Solar System, also known as a cubewano. With a likely diameter of at least 600 kilometers (400 miles), it is approximately tied with 2002 MS4 and 2013 FY27 (to within measurement uncertainties) as the largest unnamed object in the Solar System. It was discovered at Palomar Observatory in 2002.

    <span class="nowrap">(55637) 2002 UX<sub>25</sub></span> Spitzer dwarf-planet candidate

    (55637) 2002 UX25 (provisional designation 2002 UX25) is a trans-Neptunian object that orbits the Sun in the Kuiper belt beyond Neptune. It briefly garnered scientific attention when it was found to have an unexpectedly low density of about 0.82 g/cm3. It was discovered on 30 October 2002, by the Spacewatch program; as of August 2024, the object has yet to be named.

    <span class="mw-page-title-main">174567 Varda</span> Trans-Neptunian object

    174567 Varda (provisional designation 2003 MW12) is a binary trans-Neptunian planetoid of the resonant hot classical population of the Kuiper belt, located in the outermost region of the Solar System. Its moon, Ilmarë, was discovered in 2009.

    <span class="nowrap">(26308) 1998 SM<sub>165</sub></span>

    (26308) 1998 SM165 is a resonant trans-Neptunian object and binary system from the Kuiper belt in the outermost regions of the Solar System. It was discovered on 16 September 1998, by American astronomer Nichole Danzl at the Kitt Peak National Observatory in Arizona. It is classified as a twotino and measures approximately 280 kilometers in diameter. Its minor-planet moon was discovered in 2001.

    <span class="mw-page-title-main">120347 Salacia</span> Possible dwarf planet

    Salacia is a large trans-Neptunian object in the Kuiper belt, approximately 850 km (530 mi) in diameter. It was discovered on 22 September 2004, by American astronomers Henry Roe, Michael Brown and Kristina Barkume at the Palomar Observatory in California, United States. Salacia orbits the Sun at an average distance that is slightly greater than that of Pluto. It was named after the Roman goddess Salacia and has a single known moon, Actaea.

    (35671) 1998 SN165 (provisional designation 1998 SN165) is a trans-Neptunian object from the Kuiper belt located in the outermost region of the Solar System. It was discovered on 23 September 1998, by American astronomer Arianna Gleason at the Kitt Peak National Observatory near Tucson, Arizona. The cold classical Kuiper belt object is a dwarf planet candidate, as it measures approximately 400 kilometers (250 miles) in diameter. It has a grey-blue color (BB) and a rotation period of 8.8 hours. As of 2021, it has not been named.

    <span class="mw-page-title-main">65489 Ceto</span> Minor planet

    65489 Ceto, as a binary also (65489) Ceto/Phorcys, is a binary trans-Neptunian object (TNO) discovered on March 22, 2003, by Chad A. Trujillo and Michael Brown at Palomar. It is named after the sea goddess Ceto from Greek mythology. It came to perihelion in 1989.

    <span class="nowrap">(612095) 1999 OJ<sub>4</sub></span>

    (612095) 1999 OJ4 (provisional designation 1999 OJ4) is a trans-Neptunian object and binary system from the classical Kuiper belt, located in the outermost region of the Solar System. The bright cubewano belongs to the cold population and measures approximately 75 kilometers (47 miles) in diameter. It was first observed at Mauna Kea Observatory on 18 July 1999. Discovered in 2005, its minor-planet moon is just 3 kilometers smaller than its primary and has an orbital period of 84 days.

    (508869) 2002 VT130, provisional designation 2002 VT130, is a trans-Neptunian object and binary system from the classical Kuiper belt, located in the outermost region of the Solar System. It was discovered by American astronomer Marc Buie at Kitt Peak Observatory on 7 November 2002. The primary measures approximately 324 kilometers (201 miles) in diameter.

    <span class="nowrap">(524366) 2001 XR<sub>254</sub></span>

    (524366) 2001 XR254, provisional designation 2001 XR254, is a trans-Neptunian object and binary system from the classical Kuiper belt, located in the outermost region of the Solar System. The cubewano belongs to the cold population and measures approximately 171 kilometers (110 miles). It was first observed on 10 December 2001, by astronomers at the Mauna Kea Observatory, Hawaii. Its 140-kilometer sized companion was discovered by the Hubble Space Telescope in June 2006.

    <span class="nowrap">(275809) 2001 QY<sub>297</sub></span>

    (275809) 2001 QY297 is a trans-Neptunian object from the classical Kuiper belt, located in the outermost region of the Solar System. The binary classical Kuiper belt object belongs to the cold population.

    <span class="mw-page-title-main">469705 ǂKá̦gára</span>

    469705 ǂKá̦gára (provisional designation 2005 EF298) is a trans-Neptunian object and binary system of the core Kuiper belt, located in the outermost region of the Solar System. It was discovered on 11 March 2005 by American astronomer Marc Buie at the Kitt Peak Observatory in Arizona. The primary body measures around 140 kilometers (90 miles) in diameter. Its 120-kilometer (75-mile) companion ǃHãunu was discovered with the Hubble Space Telescope in 2009. The ǂKá̦gára–ǃHãunu system is currently undergoing mutual occultation and eclipsing events in which one body casts a shadow on or obstructs the view of the other as seen from Earth.

    References

    1. 1 2 3 4 5 "1998 WW31". Minor Planet Center. Retrieved 10 October 2018.
    2. 1 2 3 "List Of Transneptunian Objects". Minor Planet Center. Retrieved 10 October 2018.
    3. 1 2 3 4 "The binary Kuiper-belt object 1998 WW31" (PDF). Nature. 18 April 2002. Retrieved 10 October 2018.
    4. 1 2 3 4 "JPL Small-Body Database Browser: (1998 WW31)" (2011-12-24 last obs.). Jet Propulsion Laboratory . Retrieved 10 October 2018.
    5. 1 2 3 Johnston, Wm. Robert (30 December 2017). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 10 October 2018.
    6. 1 2 3 4 5 Johnston, Wm. Robert (31 January 2015). "Asteroids with Satellites Database – 1998 WW31 and S/2000 (1998 WW31) 1". Johnston's Archive. Retrieved 10 October 2018.
    7. 1 2 3 4 Veillet, C.; Doressoundiram, A.; Shapiro, J.; Kavelaars, J. J.; Morbidelli, A. (April 2001). "S/2000 (1998 WW_31) 1". IAU Circ. 7610 (7610): 1. Bibcode:2001IAUC.7610....1V . Retrieved 10 October 2018.
    8. 1 2 3 4 5 6 7 "LCDB Data for (1998 WW31)". Asteroid Lightcurve Database (LCDB). Retrieved 10 October 2018.
    9. 1 2 Grundy, W.M.; Noll, K.S.; Roe, H.G.; Buie, M.W.; Porter, S.B.; Parker, A.H.; Nesvorný, D.; Levison, H.F.; Benecchi, S.D.; Stephens, D.C.; Trujillo, C.A. (December 2019). "Mutual orbit orientations of transneptunian binaries". Icarus. 334: 62–78. doi:10.1016/j.icarus.2019.03.035.
    10. 1 2 3 4 5 Brown, Michael E. "How many dwarf planets are there in the outer solar system?". California Institute of Technology . Retrieved 10 October 2018.
    11. 1 2 Hainaut, O. R.; Boehnhardt, H.; Protopapa, S. (October 2012). "Colours of minor bodies in the outer solar system. II. A statistical analysis revisited". Astronomy and Astrophysics. 546: 20. arXiv: 1209.1896 . Bibcode:2012A&A...546A.115H. doi:10.1051/0004-6361/201219566. S2CID   54776793.
    12. 1 2 3 "Asteroid 1998 WW31". Small Bodies Data Ferret. Retrieved 10 October 2018.
    13. ↑ Fornasier, S.; Dotto, E.; Hainaut, O.; Marzari, F.; Boehnhardt, H.; De Luise, F.; et al. (October 2007). "Visible spectroscopic and photometric survey of Jupiter Trojans: Final results on dynamical families". Icarus. 190 (2): 622–642. arXiv: 0704.0350 . Bibcode:2007Icar..190..622F. doi:10.1016/j.icarus.2007.03.033. S2CID   12844258.
    This page is based on this Wikipedia article
    Text is available under the CC BY-SA 4.0 license; additional terms may apply.
    Images, videos and audio are available under their respective licenses.