85D / Boethin
| 85D / Boethin [i] | |
|---|---|
| Properties of the orbit ( animation ) | |
| Orbit type | short-term |
| Numerical eccentricity | 0.781 |
| Perihelion | 1.13 AU |
| Aphelion | 9.24 AU |
| Major semi-axis | 5.18 AU |
| Sidereal period | 11.81 a |
| Inclination of the orbit plane | 4.3 ° |
| Perihelion | December 12, 2008 |
| Orbital velocity in the perihelion | 37.3 km / s |
| history | |
| Explorer | L. Boethin |
| Date of discovery | 4th January 1975 |
| Older name | 1975 I, 1986 I, 1975a, 1985n |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles . | |
85D / Boethin is a short-period comet , the target for the expanded mission of NASA -Raumsonde Deep Impact was talking.
discovery
The comet was discovered on January 4, 1975 by the priest and amateur astronomer Leo Boethin in the Philippines at an apparent magnitude of about 12 mag. Soon afterwards, the orbit determination showed that it was a short-period comet.
Orbit
The comet moves in an elliptical orbit around the sun , with the point of its orbit closest to the sun ( perihelion ) just outside the orbit of the earth , and the point furthest away from the sun ( aphelion ) lies somewhat within the orbit of Saturn . The eccentricity of the orbit is 0.781, the plane of the orbit is inclined about 4 ° to the ecliptic . The comet's orbital period is 11.81 years .
After 1975, the comet could also be observed when it returned in 1986, where it even reached a brightness of up to 8 mag. Its next return was predicted for the spring of 1997, but no observations of the comet are available.
Mission goal for Deep Impact
The comet was discussed as a target for NASA's Deep Impact spacecraft's extended mission known as EPOXI . The probe should reach the comet in late 2008. After the comet was not found again by December 2007, the probe headed for comet 103P / Hartley 2 instead . Comet Boethin may have broken into smaller fragments since it was last observed and could no longer be seen from Earth.
See also
Web links
Individual evidence
- ↑ NASA: NASA Sends Spacecraft on Mission to Comet Hartley 2 , December 13, 2007