Discovery [1] | |
---|---|
Discovered by | J. H. Metcalf |
Discovery site | Winchester Obs. ( 799 ) |
Discovery date | 20 March 1914 |
Designations | |
(784) Pickeringia | |
Named after |
|
A914 FC ·1914 UM | |
Orbital characteristics [3] | |
Epoch 31 May 2020 (JD 2459000.5) | |
Uncertainty parameter 0 | |
Observation arc | 105.82 yr (38,652 d) |
Aphelion | 3.8458 AU |
Perihelion | 2.3455 AU |
3.0956 AU | |
Eccentricity | 0.2423 |
5.45 yr (1,989 d) | |
97.354° | |
0° 10m 51.6s / day | |
Inclination | 12.284° |
14.917° | |
238.01° | |
Physical characteristics | |
Mass | (3.74±0.32)×1018 kg [10] |
Mean density | 12.70±3.49 g/cm3 [10] |
13.144±0.005 h [11] | |
Pole ecliptic latitude |
|
784 Pickeringia ( prov. designation:A914 FCor1914 UM) is a large background asteroid, approximately 76 kilometers (47 miles) in diameter, located in the outer region of the asteroid belt. It was discovered on 20 March 1914, by American astronomer Joel Hastings Metcalf at the Winchester Observatory ( 799 ) in Massachusetts. [1] The dark C-type asteroid has a rotation period of 13.1 hours and an irregular shape. It was named after American astronomers Edward Charles Pickering (1846–1919) and his brother William Henry Pickering (1858–1938). [2]
Pickeringia is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. [4] [5] [6] It orbits the Sun in the outer asteroid belt at a distance of 2.3–3.8 AU once every 5 years and 5 months (1,989 days; semi-major axis of 3.1 AU). Its orbit has an eccentricity of 0.24 and an inclination of 12° with respect to the ecliptic. [3] The body's observation arc begins at Heidelberg Observatory on 30 September 1921, more than seven years after its official discovery observation at Winchester Observatory ( 799 ). [1]
This minor planet was named after American astronomers Edward Charles Pickering (1846–1919) and his brother William Henry Pickering (1858–1938), who were the directors of the Harvard Observatory and the Boyden Station at Arequipa, respectively. William Henry also discovered Phoebe, an irregular moon of Saturn. The naming was mentioned in The Names of the Minor Planets by Paul Herget in 1955 ( H 78 ). [2] The lunar crater Pickering and the Martian crater Pickering were also named in honor of the two astronomers. [13] [14]
In the Bus–Binzel SMASS classification, Pickeringia is a common, carbonaceous C-type asteroid. [3]
In January 2017, a rotational lightcurve of Pickeringia was obtained from photometric observations by the Spanish group of asteroids observers (OBAS). Lightcurve analysis gave a rotation period of 13.144±0.005 hours with a brightness variation of 0.17±0.03 magnitude ( U=2+ ). [11]
The result supersedes observations taken during the 1990s by European astronomers using the ESO 0.5-metre telescope at La Silla Observatory, Chile, which gave a period of 13 hours with an amplitude of 0.40 magnitude ( U=2 ). [15] as well as a period determination by French amateur astronomer Laurent Bernasconi in December 2004, which gave 13.17±0.05 h and an amplitude of 0.20±0.01 magnitude ( U=2 ). [16]
Two modeled lightcurves, published by Josef Ďurech and Josef Hanuš in 2016, using photometric data from the Lowell Photometric Database (LPD) and other sources, gave a sidereal period of 13.16995±0.00001 and 13.16998±0.00005, respectively. Each modeled lightcurve also determined two spin axes of (99.0°, 67.0°) and (283.0°, 30.0°), as well as (282.0°, 35.0°) and (103.0°, 68.0°) in ecliptic coordinates (λ, β), respectively. [17] [18] The online version of the Database of Asteroid Models from Inversion Techniques gives two poles at (103°, 68.0°) and (282°, 35.0°) with a nearly identical sidereal period. [lower-alpha 1]
According to the surveys carried out by the Japanese Akari satellite, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), and the Infrared Astronomical Satellite IRAS, Pickeringia measures (74.89±0.92), (75.596±0.311) and (89.42±3.4) kilometers in diameter and its surface has an albedo of (0.080±0.002), (0.086±0.014) and (0.0555±0.005), respectively. [7] [8] [9] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0423 and a diameter of 89.19 kilometers based on an absolute magnitude of 9.3. [19] while Carry gives a diameter of 82.52±7.18 km and estimates a mass of (3.74±0.32)×1018 kilogram from an unrealistic density of 12.70±3.49 g/cm3 . [10] Alternative mean-diameter measurements published by the WISE team include (70.14±18.05 km), (89.13±13.47 km) and (89.673±1.178 km) with corresponding albedos of (0.049±0.348), (0.0552±0.0109) and (0.06±0.02). [5] [19] On 7 August 2008, an asteroid occultation of Pickeringia gave a best-fit ellipse dimension of (89.0 km × 89.0 km), with a poor quality rating of 1. These timed observations are taken when the asteroid passes in front of a distant star. [5]
251 Sophia is a stony background asteroid from the outer regions of the asteroid belt. It was discovered on 4 October 1885, by astronomer Johann Palisa at the Vienna Observatory in Austria. The S-type asteroid (S/L) has a rotation period of 20.2 hours and measures approximately 28 kilometers in diameter. It was named after Sophia von Seeliger, wife of German astronomer Hugo von Seeliger (1849–1924).
391 Ingeborg is an asteroid and second-largest Mars-crosser on an eccentric orbit from the asteroid belt. It was discovered by German astronomer Max Wolf on 1 November 1894, at the Heidelberg Observatory in southwest Germany. When discovered, it was observed for a couple of weeks, and follow-up observations were made in 1901 and 1904. The stony S-type asteroid has a rotation period of 26.4 hours and measures approximately 17 kilometers in diameter. Any reference of the asteroid's name to a person is unknown.
682 Hagar is an Eunomia asteroid from the central regions of the asteroid belt. It was discovered on 17 June 1909, by German astronomer August Kopff at the Heidelberg-Königstuhl State Observatory. The presumed S-type asteroid has a short rotation period of 4.9 hours and measures approximately 19 kilometers in diameter. Possibly inspired by the asteroid's provisional designation "1909 HA", it was named for the biblical woman Hagar.
698 Ernestina is a background asteroid, approximately 27 kilometers in diameter, located in the outer regions of the asteroid belt. It was discovered on 5 March 1910, by German astronomer Joseph Helffrich at the Heidelberg-Königstuhl State Observatory. The presumed carbonaceous C-type asteroid has a rotation period of 5.0 hours. It was named after Ernst Wolf, son of German astronomer and prolific discoverer of minor planets, Max Wolf.
749 Malzovia is a stony background asteroid from the inner regions of the asteroid belt, approximately 11 kilometers in diameter. It was discovered on 5 April 1913, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The elongated S-type asteroid has a rotation period of 5.9 hours. It was named after Russian amateur astronomer Nikolai Maltsov who founded the discovering Simeïs Observatory in 1900.
786 Bredichina is a carbonaceous and very large background asteroid, approximately 104 kilometers in diameter, located in the outer region of the asteroid belt. It was discovered by German astronomer Franz Kaiser at the Heidelberg-Königstuhl State Observatory on 20 April 1914. The elongated C-type asteroid has a longer than average rotation period of 29.4 hours. It was named after Russian astronomer Fyodor Bredikhin (1831–1904).
791 Ani is a very large asteroid of the Meliboea family, located in the outer regions of the asteroid belt. It was discovered on 29 June 1914, by Russian astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula. The dark carbonaceous C-type asteroid has a rotation period of 11.2 hours and measures approximately 65.7 × 103.5 kilometers, with a mean diameter of 100 km (62 mi). It was named after the historic Armenian city of Ani.
803 Picka is a large and dark background asteroid from the outer regions of the asteroid belt. It was discovered on 21 March 1915, by Austrian astronomer Johann Palisa at the Vienna Observatory. The carbonaceous D-type asteroid has a rotation period of 5.1 hours and measures approximately 57 kilometers in diameter. It was named after Czech physician Friedrich Pick (1867–1921).
810 Atossa is a bright and elongated background asteroid from the region of the Flora family, located in the inner portion of the asteroid belt. It was discovered on 8 September 1915, by German astronomer Max Wolf at the Heidelberg-Königstuhl State Observatory in southern Germany. The presumed S-type asteroid has a rotation period of 4.4 hours and measures approximately 8 kilometers in diameter. It was named after the ancient Persian queen Atossa.
849 Ara is a large, metallic background asteroid, approximately 80 kilometers in diameter, that is located in the outer region of the asteroid belt. It was discovered on 9 February 1912, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The M-type asteroid has a short rotation period of 4.1 hours and is likely elongated in shape. It was named after the American Relief Administration (ARA) for the help given during the Russian famine of 1921–22.
877 Walküre is a dark background asteroid from the inner regions of the asteroid belt, approximately 38 kilometers in diameter. It was discovered on 13 September 1915, by Russian astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula. The carbonaceous F/C-type asteroid has a rotation period of 17.4 hours and is likely elongated in shape. It was named after the female spirit Valkyrie from Norse mythology, best known from Wagner's opera Die Walküre.
812 Adele is an elongated Eunomia asteroid from the central regions of the asteroid belt. It was discovered on 8 September 1915, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The presumed S-type asteroid has a rotation period of 5.9 hours and measures approximately 13 kilometers in diameter. It was likely named after the character "Adele" in the opera Die Fledermaus by Johann Strauss.
998 Bodea is a dark background asteroid from the outer regions of the asteroid belt, approximately 32 kilometers in diameter. It was discovered on 6 August 1923, by astronomer Karl Reinmuth at the Heidelberg Observatory in southern Germany. The presumed C-type asteroid with an irregular shape has a rotation period of 8.6 hours. It was named after German astronomer Johann Elert Bode (1747–1826).
1088 Mitaka is a bright background asteroid from the inner regions of the asteroid belt. It was discovered on 17 November 1927, by Japanese astronomer Okuro Oikawa at the old Tokyo Astronomical Observatory in Japan. The stony S-type asteroid has a notably short rotation period of 3.0 hours and measures approximately 15 kilometers in diameter. It was named after the Japanese village of Mitaka.
1119 Euboea is a background asteroid from the central region of the asteroid belt. It was discovered on 27 October 1927, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany. The asteroid has a rotation period of 11.4 hours and measures approximately 30 kilometers in diameter. It was named for the Greek island of Euboea.
1672 Gezelle, provisional designation 1935 BD, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 27 kilometers in diameter. It was discovered on 29 January 1935, by Belgian astronomer Eugène Delporte at Royal Observatory of Belgium in Uccle, Belgium. It was later named after Flemish poet and Roman Catholic priest Guido Gezelle.
1188 Gothlandia, provisional designation 1930 SB, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 12 kilometers in diameter. Discovered by astronomer Josep Comas i Solà at the Fabra Observatory in 1930, the asteroid was later named after the ancient name of the Spanish autonomous community of Catalonia.
1251 Hedera is a background asteroid from the central regions of the asteroid belt, approximately 13 kilometers in diameter. It was discovered on 25 January 1933, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany. The asteroid was named for the climbing plant Hedera, commonly known as "ivy".
1299 Mertona is a bright background asteroid from the central region of the asteroid belt. It was discovered on 18 January 1934, by French astronomer Guy Reiss at Algiers Observatory, Algeria, in northern Africa. The likely stony asteroid with an unknown spectral type has a rotation period of 5.0 hours and measures approximately 14 kilometers in diameter. It was named after English astronomer Gerald Merton.
1339 Désagneauxa, provisional designation 1934 XB, is a stony Eoan asteroid from the outer region of the asteroid belt, approximately 24 kilometers in diameter. It was discovered on 4 December 1934, by French astronomer Louis Boyer at the North African Algiers Observatory in Algeria. A few nights later, the asteroid was independently discovered by astronomers Grigory Neujmin and Eugène Delporte, at the Crimean Simeiz and Belgian Uccle Observatory, respectively. It was later named after discoverer's brother-in-law.