Sawiskera (moon)
(88611) Teharonhiawako I (Sawiskera) | |
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Provisional or systematic name | S / 2001 (88611) 1 |
Central body | (88611) Teharonhiawako |
Properties of the orbit | |
Major semi-axis | 27,300 ± 343 km |
Periapsis | 20,750 km |
Apoapsis | 33,850 km |
eccentricity | 0.240 ± 0.003 |
Orbit inclination | 60.0 ° ± 0.9 ° |
Orbital time | 825 ± 3 d |
Mean orbital velocity | 0.0012 km / s |
Physical Properties | |
Albedo | ≈ 0.09 - 0.14 |
Medium diameter | 122 ± 14 km |
Dimensions | ≈ 1.34 ± 0.27 · 10 18 kg |
Sidereal rotation | 4.7526 ± 0.0007 or 9.5055 ± 0.0010 or |
Acceleration of gravity on the surface | ≈ 00 m / s 2 |
Escape speed | ≈ 00 m / s |
discovery | |
Explorer |
|
Date of discovery | October 11, 2001 |
Remarks | Smaller component of a double asteroid system. |
Sawiskera ( Mohawk : [zaɰískɛɺa]) is the smaller component ( moon ) of the double asteroid system of the Kuiper belt - asteroids and cubewanos (88611) Teharonhiawako . Its mean diameter is about 122 kilometers, making it about 30.7% smaller than the mother asteroid .
Discovery and naming
Sawiskera was observed by JL Elliot, SD Kern and DJ Osip during observations on May 11th – 12th. Discovered October 2001 with the 6.5-meter Walter Baade telescope at the Las Campanas Observatory in Chile . Sawiskera was found at a distance of 0.6 arc seconds from the Teharonhiawako, which had been discovered just under two months earlier, with a difference in apparent brightness of 0.55. The discovery was published on October 15, 2001; the companion was given the provisional designation S / 2001 (88611) 1 . The two names of the system were suggested by RJ Benecchi and SD Kern.
On 29 May 2007, the Moon, among others, along with the very bright was Comet C / 2006 P1 (McNaught) , of the International Astronomical Union officially (IAU) to Sawískera named, the evil twin brother of Teharonhiawáko in the founding mythology of the Haudenosaunee is . Sawískera was a skilled hunter, however, he was cruel, jealous, and destructive, and he was eventually killed by his brother. It is said that the name should not be pronounced at night.
Track properties
Orbit
Sawiskera orbits Teharonhiawako in a prograde , elliptical orbit between 20,750 and 33,850 km from its center (major orbit half-axis 27,300 km or approx. 310.2 Teharonhiawako or 447.5 Sawisker radii). Since both revolve around the common center of gravity , the system is to be understood as a double asteroid system. The orbit eccentricity is 0.240, the orbit is 60.0 ° inclined to the ecliptic .
Sawiskera and Teharonhiawako orbit each other in 825 days or 2 years and 95 days, i.e. even longer than the planet Mars needs to get around the sun (!). This corresponds to about 128.8 orbits in a Teharonhiawako year (about 290.99 earth years).
rotation
Sawiskera has its own rotation period , which is either 4 h 45.1 m or 9 h 30.3 m, according to other information 5 h 30 m.
Physical Properties
Sawiskera has an estimated diameter of 122 km (about 69.3% of the central body), based on the assumed equal reflectivity of 9-14% for Teharonhiawako. The surface is therefore relatively dark. Like Teharonhiawako, its density is estimated at around 1.5 g / cm 3 .
exploration
Since its discovery in 2001, Sawiskera could only be observed through earth-based telescopes and its orbital elements could be determined.
See also
Web links
- Wm. Robert Johnston: (88611) Teharonhiawako and Sawiskera
- International Astronomical Union Circular No. 7733 October 15, 2001 (Discovery)
- International Astronomical Union Circular No. 7765 December 4, 2001 (observation details )
- International Astronomical Union Circular No. 8840 May 29, 2007 (designation)