109P / Swift-Tuttle
| 109P / Swift-Tuttle [i] | |
|---|---|
| Properties of the orbit ( animation ) | |
| Orbit type | short-term |
| Numerical eccentricity | 0.963 |
| Perihelion | 0.960 AU |
| Aphelion | 51.225 AU |
| Major semi-axis | 26.092 AU |
| Sidereal period | 133 a 103 d |
| Inclination of the orbit plane | 113.454 ° |
| Perihelion | December 11, 1992 |
| Orbital velocity in the perihelion | 42.59 km / s |
| Physical properties of the core | |
| Medium diameter | 26 km |
| history | |
| Explorer | L. Swift , HP Tuttle |
| Date of discovery | July 16, 1862 |
| Older name | 1862 III, 1992t |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles . | |
Swift-Tuttle (official name 109P / Swift-Tuttle ) is a short- period comet that was discovered independently on July 16, 1862 by Lewis A. Swift and on July 19, 1862 by Horace Parnell Tuttle .
Over the centuries, many particles of the comet have spread along its path, causing the well-known meteor shower of the Perseids , the shooting stars can be observed every year in mid August.
Orbit
In around 133 years the comet will orbit the sun in an elliptical orbit between 0.96 ( perihelion ) and 51.23 ( aphelion ) astronomical units , the orbital eccentricity is 0.963. The orbit is about 67 ° inclined to the ecliptic , but since the comet moves retrograde (retrograde) around the sun, its orbit inclination is given as 113 °. Its perihelion speed is 42.6 km / s.
history
On his return in 1862, the comet approached up to 0.34 AE to the earth . It reached an apparent magnitude of up to 2 mag and its tail a length of up to 30 °.
A determination of the orbit from the observations of 1862 revealed an orbital period of 120 years, so that the comet's return was initially expected in 1981. But the comet could not be found. Assuming that the comet bowlers of 1737 (C / 1737 N1 aka 1737 II) was an earlier appearance of Swift-Tuttle, who said US - astronomer Brian Marsden his return for 1992 ahead. In fact, Swift-Tuttle was found on September 26, 1992 by the Japanese amateur astronomer Tsuruhiko Kiuchi. Since the comet never came closer than 1.16 AU on this return to Earth, it only achieved a maximum apparent magnitude of 5 mag.
The comet Swift-Tuttle can also come very close to the earth, even a collision with the earth cannot be ruled out over long periods of time. At the next comet return, expected in 2126, there is no danger, as the comet will not approach closer than about 0.15 AU (about 25 million kilometers).
The great comets of the years 69 BC described by Chinese astronomers . BC and 188 AD could be explained as appearances of the comet Swift-Tuttle.
Mother body of the Perseids
In 1866, the Italian astronomer Giovanni Schiaparelli recognized that the orbit of comet Swift-Tuttle and the orbits derived for the meteoroids in the Perseids meteor shower are similar. This was the first time that a mother body of a meteor shower could be identified: The comet loses matter with every revolution. Every year around August 12th when the earth crosses the orbit of comet Swift-Tuttle, comet particles enter the earth's atmosphere at high speed and light up as meteors .
See also
Web links
Individual evidence
- ↑ 109P / Swift-Tuttle in the Small-Body Database of the Jet Propulsion Laboratory (English).