Comet Peters - Hartley (80P / Peters – Hartley) is a short-period comet from the Jupiter family. It was discovered on June 26, 1846 by the American astronomer Christian Peters at the Capodimonte Observatory . He discovered it in the constellation Libra and described it as a very faint foggy object without a clear center with a brightness of not more than 19 m magnitude. The data collected during the observation period were not enough to accurately calculate the comet’s orbit, and as a result, the comet was considered lost for nearly one and a half centuries until July 11, 1982, was accidentally discovered by English astronomer Malcolm Hartley using the 1.2-meter telescope of the Schmidt system at the Siding Spring Observatory . It had a brightness of 15 m and was surrounded by a faint halo, which allowed it to be identified as a comet. It has a rather short period of revolution around the Sun - just over 8 years.
- Orbit of Comet Peters - Hartley and its position in the solar system
| 80P / Peters - Hartley | |
|---|---|
| Opening | |
| Discoverer | Christian Peters ; Malcolm Hartley |
| opening date | June 26, 1846 |
| Alternative designations | 1846 M1; 1982 N1 |
| Orbital characteristics [1] | |
| Epoch of September 8, 2014 JD 2456908.5 | |
| Eccentricity | 0.5989902 |
| Semi-axis ( a ) | 601.632 million km (4.0216596 a. E.) |
| Perihelion ( q ) | 241.26 million km (1.6127249 a. E.) |
| Afhelia ( Q ) | 962.003 million km (6,4305943 a. E.) |
| Period of circulation ( P ) | 2945,821 days (8.065 g. ) |
| Orbit inclination | 29.92275 ° |
| Last perihelion | November 10, 2014 |
| Next perihelion | December 8, 2022 [2] [3] |
| physical characteristics | |
Observation history
The calculations showed that the comet passed the perihelion point of 1.5 a. e. (150 million km) on June 3, and the next day, June 4, passed the point of closest approach to Earth at 0.55 a. e. (82.5 million km). Soon after its discovery, the comet faded noticeably and was last observed on July 21, 1946. Using the three starting points at which the comet was located, Christian Peters received the first version of a parabolic orbit, according to which the perihelion date was April 12, 1946. Later, taking into account the observations made in July, he corrected the obtained result, which led to a shift in the date of the perihelion to May 31. German astronomer Heinrich Ludwig d'Arry set the perihelion date for June 1, and the orbital period at 15.89 years, but in 1948 revised the result and reduced the estimated period to 12.85 years. In 1887, astronomers have already missed two of the alleged return of the comet, so Berberich tried again to calculate the comet's orbit based on the 16 positions already received for 1946, which gave an orbital period of 13.38 years. However, as Berberich pointed out in 1856 and 1883, the comet made close encounters with Saturn , which could greatly affect its orbit. The next attempt to calculate the comet's orbit took place only a hundred years later, when Buckley examined 1846 positions and taking into account possible perturbations from seven planets, determined the orbital period of 12.71 years, but still gave an uncertainty of about 3 years.
The comet was re-discovered in 1982 by MP Candy in Australia, which, along with Japanese astronomers I. Hasegawa and S. Nakano, came to the conclusion that it was identical with the 1946 comet. This conclusion was mathematically confirmed on July 22 by the calculations of Brian Marsden , who calculated the motion of the comet in orbit in the opposite direction until 1946 and determined that it falls approximately at the same point where it was discovered by Christian Peters in 1946. He determined that for 1946 the orbital period of the comet was 7.88 years. For 1982, the comet's circulation period is 8.12 years.
During its next appearance in 1990, a comet was observed on June 26 by Robert McNaught at the Saydin Spring Observatory . He described the comet as a diffuse object of 15 m . The brightness of the comet continued to increase until the beginning of June and reached 13 m . The last time this year the comet was observed on June 20, when its brightness dropped to 16 m magnitude.
In 1998, the location of the comet relative to the Earth was unfavorable, so it was possible to observe it only in the period of February 16 and April 25, and its brightness did not exceed 16 m magnitude.
Notes
- ↑ Elements and Ephemeris for 80P / Peters-Hartley . Minor Planet Center. The appeal date is May 26, 2016.
- ↑ Seiichi Yoshida. 80P / Peters-Hartley . Seiichi Yoshida's Comet Catalog (July 3, 2010). The appeal date is February 18, 2012.
- ↑ Syuichi Nakano (English) . 80P / Peters-Hartley (NK 2075) . OAA Computing and Minor Planet Sections (February 4, 2012). The appeal date is February 18, 2012.
Links
- NASA JPL Database on Small Bodies of the Solar System (80P) (English)
- MPC Database on Small Bodies of the Solar System (80P) (eng.)
- 80P at Kronk's Cometography
- 80P at Kazuo Kinoshita's Comets
| Short-period comets with numbers | ||
|---|---|---|
| ◄ 78P / Gerells • 79P / du Touat - Hartley • 80P / Peters - Hartley • 81P / Wilda • 82P / Gerells ► | ||