Discovery [1] | |
---|---|
Discovered by | O. Oikawa |
Discovery site | Tokyo Astronomical Obs. |
Discovery date | 17 November 1927 |
Designations | |
(1089) Tama | |
Pronunciation | Japanese: [tama] |
Named after | Tama River [2] (Japanese river) |
1927 WB ·1930 ST 1952 HE4 ·A894 VA A904 VD ·A919 HA | |
main-belt ·(inner) Flora [3] · background [4] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 (JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 122.40 yr (44,708 days) |
Aphelion | 2.4951 AU |
Perihelion | 1.9327 AU |
2.2139 AU | |
Eccentricity | 0.1270 |
3.29 yr (1,203 days) | |
82.843° | |
0° 17m 57.12s / day | |
Inclination | 3.7264° |
71.489° | |
354.29° | |
Known satellites | 1 [3] [5] [6] |
Physical characteristics | |
Dimensions | 11.33±2.00 km [7] 12.2±1.6 km [8] 12.82 km (derived) [3] 12.92±0.6 km [9] 13.08±0.37 km [10] 13.082±0.373 km [10] 13.32±0.19 km [11] |
4(dated) h [12] 16.4±0.1 h [13] 16.44 h [8] 16.444±0.001 h [14] 16.4442±0.0004 h [6] [13] 16.445±0.005 h [13] 16.45±0.05 h [13] 16.4530±0.0004 h [13] 16.464±0.004 h [15] 16.4655 h [16] | |
0.2048 (derived) [3] 0.216±0.029 [10] 0.2424±0.023 [9] 0.243±0.008 [11] 0.267±0.083 [8] 0.32±0.23 [7] | |
S (assumed) [3] | |
11.60 [9] [11] ·11.63±0.0 [8] ·11.70 [7] [10] ·11.8 [1] [3] ·11.86±0.85 [17] | |
1089 Tama, provisional designation 1927 WB, is an elongated Florian asteroid and synchronous binary system from the inner regions of the asteroid belt, approximately 12 kilometers in diameter.
It was discovered by Japanese astronomer Okuro Oikawa at the old Tokyo Astronomical Observatory ( 389 ) on 17 November 1927. [18] The asteroid was named after the Tama River in Japan. [2] Its minor-planet moon was discovered in December 2003 and measures approximately 9 kilometers. [6]
Tama is a member of the Flora family ( 402 ), a giant asteroid family and the largest family of stony asteroids in the main-belt. [3] It is, however, a non-family asteroid from the main belt's background population when applying the Hierarchical Clustering Method to its proper orbital elements. [4]
The asteroid orbits the Sun in the inner main-belt at a distance of 1.9–2.5 AU once every 3 years and 3 months (1,203 days). Its orbit has an eccentricity of 0.13 and an inclination of 4° with respect to the ecliptic. [1] Tama was first identified as A894 VA at Heidelberg Observatory in November 1894. The body's observation arc begins with its identification as A904 VD at Heidelberg in November 1904, or 23 years prior to its official discovery observation at Tokyo. [18]
Tama is an assumed stony S-type asteroid. [3]
A large number of rotational lightcurves of Tama were obtained from photometric observations since it has been identified as a binary asteroid (see below). Lightcurve analysis gave a rotation period between 16.4 and 16.464 hours with a brightness variation between 0.08 and 0.41 magnitude ( U=2-/2-3-/3 ), superseding a period of 4 hours from a fragmentary lightcurve obtained in the 1990s ( U=1 ). [6] [8] [12] [13] [15]
Tama appears to be somewhat elongated in shape. [6] LCDB's consolidated result gives a period of 16.44 hours and an amplitude of 0.41 magnitude ( U=3 ). [3]
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, the Spitzer Space Telescope and the NEOWISE mission of the Wide-field Infrared Survey Explorer, Tama measures between 11.33 and 13.32 kilometers in diameter and its surface has an albedo between 0.216 and 0.32. [7] [8] [9] [10] [11]
The Collaborative Asteroid Lightcurve Link derives an albedo of 0.2048 and a diameter of 12.82 kilometers based on an absolute magnitude of 11.8. [3]
In 2004, it was announced that Tama has a minor-planet moon, provisionally designated S/2003 (1089) 1. The satellite was identified based on lightcurve observations with mutual occultation and eclipsing events from 24 December 2003 to 5 January 2004 by Raoul Behrend, René Roy, Claudine Rinner, Pierre Antonini, Petr Pravec, Alan Harris, Stefano Sposetti, Russell Durkee, and Alain Klotz. [6] [13] The moon measures approximately 9 kilometers in diameter. It may orbits 20 km away in a period of 16.4442 hours (synchronously). [3] [5] [6]
Tamas lightcurve has also been modeled. In 2013, modelling by an international study using photometric data from the US Naval Observatory, the Uppsala Asteroid Photometric Catalogue (UAPC) and the Palmer Divide Observatory, gave a concurring rotation period of 16.4655 hours. [16] Another modeled lightcurve using data from UAPC, the Palomar Transient Factory survey, and individual observers, gave a period of 16.4461 hours as well as two spin axes of (193.0°, 32.0°) and (9.0°, 28.0°) in ecliptic coordinates (λ, β). [19]
This minor planet was named after Tama River near the discovering Tokyo Astronomical Observatory ( 389 ) in Japan. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 ( H 103 ). [2]
1620 Geographos, provisional designation 1951 RA, is a highly elongated, stony asteroid, near-Earth object and potentially hazardous asteroid of the Apollo group, with a mean-diameter of approximately 2.5 km (1.6 mi). It was discovered on 14 September 1951, by astronomers Albert George Wilson and Rudolph Minkowski at the Palomar Observatory in California, United States. The asteroid was named in honor of the National Geographic Society.
1509 Esclangona, provisional designation 1938 YG, is a rare-type Hungaria asteroid and binary system from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It is named after French astronomer Ernest Esclangon.
Columbia is a stony asteroid from the middle region of the asteroid belt, approximately 26 kilometers in diameter. It was discovered on 22 March 1892, by French astronomer Auguste Charlois at Nice Observatory in southeast France. It is named after Christopher Columbus (1451–1506).
1313 Berna, provisional designation 1933 QG, is a background asteroid and synchronous binary system from the Eunomian region in the central asteroid belt, approximately 14 kilometers in diameter. It was discovered on 24 August 1933, by Belgian astronomer Sylvain Arend at the Uccle Observatory in Belgium. The assumed S-type asteroid has a longer-than average rotation period of 25.5 hours and is likely elongated in shape. It was named for the Swiss capital of Bern. The discovery of an 11-kilometer-sized companion was announced in February 2004.
4492 Debussy is a dark and elongated background asteroid and binary system from the intermediate asteroid belt, approximately 15 kilometers in diameter. It was discovered on 17 September 1988, by Belgian astronomer Eric Elst at Haute-Provence Observatory in France. It was later named after French composer Claude Debussy.
1046 Edwin, provisional designation 1924 UA, is a background asteroid from the outer regions of the asteroid belt, approximately 30 kilometers kilometers in diameter. It was discovered on 1 December 1924, by Belgian–American astronomer George Van Biesbroeck at the Yerkes Observatory in Wisconsin, United States, who named it after his son, Edwin Van Biesbroeck. The potentially metallic asteroid has a short rotation period of 5.29 hours.
1075 Helina, provisional designation 1926 SC, is a stony Eos asteroid from the outer regions of the asteroid belt, approximately 34 kilometers in diameter. It was discovered on 29 September 1926, by astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula. The asteroid was named after the discoverer's son, Helij Neujmin.
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.
1095 Tulipa is an Eos asteroid from the outer regions of the asteroid belt. It was discovered by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany on 14 April 1926. The assumed S-type asteroid has a rotation period of 2.8 hours and measures approximately 30 kilometers in diameter. It was named after the flower Tulip. Originally, the name was redundantly assigned to Florian asteroid 1449 Virtanen.
1675 Simonida, provisional designation 1938 FB, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 11 kilometers in diameter. Discovered by Milorad Protić in 1938, it was later named after the medieval Byzantine princess Simonida.
3225 Hoag, provisional designation 1982 QQ, is a dynamical Hungaria asteroid from the innermost regions of the asteroid belt, approximately 5.5 kilometers in diameter. It was discovered on 20 August 1982, by American astronomer couple Carolyn and Eugene Shoemaker at the Palomar Observatory in California. The stony S/L-type asteroid has a short rotation period of 2.37 hours. It was named for American astronomer Arthur Hoag.
3960 Chaliubieju, provisional designation 1955 BG, is a stony asteroid from the central regions of the asteroid belt, approximately 9 kilometers in diameter. It was discovered on 20 January 1955, by astronomers at the Purple Mountain Observatory in Nanjing, China. The asteroid was named after Cha Liubieju, a friend of one of the discoverers.
1453 Fennia, provisional designation 1938 ED1, is a stony Hungaria asteroid and synchronous binary system from the innermost regions of the asteroid belt, approximately 7 kilometers in diameter. Discovered by Yrjö Väisälä at the Turku Observatory in 1938, the asteroid was later named after the Nordic country of Finland. The system's minor-planet moon was discovered in 2007. It has a derived diameter of 1.95 kilometers and is orbiting its primary every 23.55 hours.
1736 Floirac, provisional designation 1967 RA, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8.7 kilometer in diameter.
1382 Gerti, provisional designation 1925 BB, is a Florian asteroid from the inner regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 21 January 1925, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany. The asteroid was named after a secretary of the Astronomical Calculation Institute, Gertrud Höhne.
1177 Gonnessia, provisional designation 1930 WA, is a dark background asteroid from the outer regions of the asteroid belt, approximately 99 kilometers in diameter. It was discovered on 24 November 1930, by French astronomer Louis Boyer at the Algiers Observatory in Algeria, North Africa, and named after astronomer François Gonnessiat.
1281 Jeanne is a dark asteroid from the background population of the intermediate asteroid belt. It was discovered on 25 August 1933, by astronomer Sylvain Arend at the Royal Observatory of Belgium in Uccle, who named it after his daughter, Jeanne. The likely P-type asteroid has a rotation period of 15.2 hours and measures approximately 22 kilometers in diameter.
1297 Quadea, provisional designation 1934 AD, is an Eoan asteroid from the outer regions of the asteroid belt, approximately 23 kilometers in diameter. It was discovered on 7 January 1934, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in Germany. The asteroid was named for the parents-in-law of the discoverer's brother.
7776 Takeishi, provisional designation 1993 BF, is a background asteroid from the inner regions of the asteroid belt, approximately 6 kilometers in diameter. It was discovered on 20 January 1993, by Japanese astronomer Takeshi Urata at the Nihondaira Observatory in Japan. The assumed S-type asteroid has a rotation period of 8.9 hours. It was named after Japanese amateur astronomer Masanori Takeishi.
1407 Lindelöf, provisional designation 1936 WC, is an asteroid from the central region of the asteroid belt, approximately 20 kilometers in diameter. It was discovered on 21 November 1936, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland. The asteroid was named after Finnish topologist Ernst Lindelöf.