Discovery [1] | |
---|---|
Discovered by | C. Shoemaker |
Discovery site | Palomar Obs. |
Discovery date | 24 January 1988 |
Designations | |
(4217) Engelhardt | |
Named after | Wolf von Engelhardt (German mineralogist) [2] |
1988 BO2 ·1944 RL 1951 RY1 ·1970 AA | |
main-belt · Phocaea [3] [4] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 (JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 72.73 yr (26,563 days) |
Aphelion | 2.8045 AU |
Perihelion | 1.8246 AU |
2.3145 AU | |
Eccentricity | 0.2117 |
3.52 yr (1,286 days) | |
272.23° | |
0° 16m 47.64s / day | |
Inclination | 23.129° |
355.44° | |
348.79° | |
Known satellites | 1 (P: 36.03 h) [5] [lower-alpha 1] |
Physical characteristics | |
Dimensions | 7.34±1.36 km [6] 8.742±0.356 km [7] [8] 9.16±1.0 km [9] 9.24 km (derived) [3] |
3.066±0.001 h [10] 3.0661±0.0002 h [5] [lower-alpha 1] | |
0.2108±0.052 [9] 0.231±0.046 [7] [8] 0.2489 (derived) [3] 0.37±0.17 [6] | |
S [3] [11] | |
12.10±0.67 [11] ·12.20 [6] ·12.3 [1] [3] ·12.50 [7] [9] | |
4217 Engelhardt, provisional designation 1988 BO2, is a stony Phocean asteroid and a potentially binary system from the inner regions of the asteroid belt, approximately 9 kilometers in diameter. It was discovered on 24 January 1988, by American astronomer Carolyn Shoemaker at Palomar Observatory in California, and later named after German mineralogist Wolf von Engelhardt. [12]
Engelhardt is a stony S-type asteroid and a member of the Phocaea family ( 701 ). [4] It orbits the Sun in the inner main-belt at a distance of 1.8–2.8 AU once every 3 years and 6 months (1,286 days). Its orbit has an eccentricity of 0.21 and an inclination of 23° with respect to the ecliptic. [1]
It was first identified as 1944 RL at Turku Observatory in 1944, extending the body's observation arc by 44 years prior to its official discovery observation at Palomar. [12] It will pass about 0.0017 AU (250,000 km) from Earth threatening asteroid (29075) 1950 DA in 2736. [13]
In November 2004, a rotational lightcurve of Engelhardt was obtained from photometric observations by American astronomer Brian Warner at this Palmer Divide Observatory in Colorado. [lower-alpha 1] Lightcurve analysis gave a well-defined rotation period of 3.066 hours with a brightness amplitude of 0.16 magnitude ( U=3 ). [10]
In December 2011, a follow-up observation by Warner gave a period of 3.0661 hours with 0.18 amplitude ( U=3 ). [5] Due to a couple of supposed occultation and eclipsing events, Warner also suspects that Engelhardt might by a binary system with a minor-planet moon orbiting it every 36.03 hours. The result, however, is far from conclusive. [lower-alpha 1]
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Engelhardt measures between 7.34 and 9.16 kilometers in diameter and its surface has an albedo between and 0.231 and 0.37. [7] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.2489 and a diameter of 9.24 kilometers with on an absolute magnitude of 12.3. [3]
Baltic German geologist and mineralogist Wolf von Engelhardt (1910–2008), expert on impact craters and related mineral metamorphism. He was a professor at the University of Tübingen and a longtime director of its Institute of Mineralogy and Petrography. [2] The approved naming citation was published by the Minor Planet Center on 27 June 1991 ( M.P.C. 18456). [14]
1575 Winifred, provisional designation 1950 HH, is a stony Phocaea asteroid and slow rotator from the inner regions of the asteroid belt, approximately 9.5 kilometers in diameter.
2023 Asaph, provisional designation 1952 SA, is a dark asteroid from the outer regions of the asteroid belt, approximately 21 kilometers in diameter. It was discovered on 16 September 1952, by astronomers of the Indiana Asteroid Program at Goethe Link Observatory in Indiana, United States.
Arago, provisional designation 1923 OT, is a dark asteroid from the outer regions of the asteroid belt, approximately 55 kilometers in diameter. It was discovered on 5 September 1923, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The asteroid was named after French mathematician François Arago.
Lagrangea, provisional designation 1923 OU, is a carbonaceous background asteroid from the outer region of the asteroid belt, approximately 30 kilometers in diameter. It was discovered on 12 September 1923, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The asteroid was named after Italian mathematician and astronomer Joseph-Louis Lagrange.
1151 Ithaka, provisional designation 1929 RK, is a carbonaceous asteroid from the inner regions of the asteroid belt, approximately 14 kilometers in diameter. It was discovered by Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in 1929, and later named for the Greek island of Ithaca.
6398 Timhunter, provisional designation 1991 CD1, is a stony Phocaea asteroid from the inner regions of the asteroid belt, approximately 5.5 kilometers in diameter. It was discovered on 10 February 1991, by American astronomer couple Carolyn and Eugene Shoemaker, in collaboration with Canadian astronomer David H. Levy at Palomar Observatory in California, United States. It was named for American amateur astronomer Tim Hunter.
2678 Aavasaksa, provisional designation 1938 DF1, is a stony Flora asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter.
2839 Annette is a bright Flora asteroid from the inner regions of the asteroid belt. It was discovered on 5 October 1929, by American astronomer Clyde Tombaugh at Lowell Observatory during his search for Pluto. The presumed S-type asteroid has a rotation period of 10.5 hours and measures approximately 5 kilometers in diameter. It was named after the discoverer's daughter.
1335 Demoulina, provisional designation 1934 RE, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 7 kilometers in diameter. Discovered by Karl Reinmuth at Heidelberg Observatory in 1934, the asteroid was named after Prof. Demoulin, a Belgian astronomer at Ghent University. It has a slower-than average spin rate of nearly 75 hours.
3996 Fugaku, provisional designation 1988 XG1, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 5.5 kilometers in diameter. It was discovered on 5 December 1988, by Japanese amateur astronomers Masaru Arai and Hiroshi Mori at Yorii Observatory in central Japan. It was named for Mount Fuji, Japan.
1930 Lucifer, provisional designation 1964 UA, is a carbonaceous asteroid from the outer regions of the asteroid belt, approximately 34 kilometers in diameter. It was discovered on 29 October 1964, by American astronomer Elizabeth Roemer at the Flagstaff station (NOFS) of the United States Naval Observatory (USNO). It is named after Lucifer, the "shining one" or "light-bearer" from the Hebrew Bible.
1582 Martir, provisional designation 1950 LY, is a carbonaceous background asteroid from the outer regions of the asteroid belt, approximately 37 kilometers in diameter. It was discovered on 15 June 1950, by Argentine astronomer Miguel Itzigsohn at the La Plata Astronomical Observatory in Argentina. The asteroid was named after the First Lady of Argentina, Eva Perón.
1680 Per Brahe, provisional designation 1942 CH, is a bright background asteroid from the central region of the asteroid belt, approximately 14 kilometers in diameter. It was discovered on 12 February 1942, by Finnish astronomer Liisi Oterma at Turku Observatory in Southwest Finland. The stony S-type asteroid has a rotation period of 3.4 hours. It is named after Swedish count and governor Per Brahe the Younger.
1518 Rovaniemi, provisional designation 1938 UA, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. Discovered by Yrjö Väisälä at the Turku Observatory in 1938, the asteroid was later named after the Finnish city of Rovaniemi.
4176 Sudek, provisional designation 1987 DS, is a Themistian asteroid from the outer regions of the asteroid belt, approximately 17 kilometers in diameter. It was discovered on 24 February 1987, by Czech astronomer Antonín Mrkos at the Kleť Observatory in the Czech Republic. The presumed C-type asteroid has a rotation period of 8.16 hours. It was named in memory of Czech photographer Josef Sudek.
2391 Tomita, provisional designation 1957 AA, is a Nysian asteroid from the inner regions of the asteroid belt, approximately 15 kilometers in diameter. The asteroid was discovered on 9 January 1957, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany. It was named after Japanese astronomer Kōichirō Tomita.
3823 Yorii, provisional designation 1988 EC1, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 11 kilometers in diameter.
3628 Božněmcová, provisional designation 1979 WD, is a rare-type asteroid from the middle region of the asteroid belt, approximately 7 kilometers in diameter. It was discovered on 25 November 1979, by Czech astronomer Zdeňka Vávrová at Kleť Observatory in the Czech Republic. It is named for Czech writer Božena Němcová.
1422 Strömgrenia, provisional designation 1936 QF, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 5.5 kilometers in diameter. It was discovered on 23 August 1936, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after Swedish-Danish astronomer Svante Elis Strömgren.
10208 Germanicus, provisional designation 1997 QN1, is a stony Florian asteroid and binary system from the inner regions of the asteroid belt, approximately 3.5 kilometers in diameter.