Discovery [1] | |
---|---|
Discovered by | K. Reinmuth |
Discovery site | Heidelberg Obs. |
Discovery date | 7 February 1935 |
Designations | |
(1720) Niels | |
Named after | Niels (discoverer's grandson) [2] |
1935 CQ · 1940 WH 1951 AL · 1953 VO1 1959 RA · 1963 WE | |
main-belt · ( inner) [3] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 ( JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 89.52 yr (32,697 days) |
Aphelion | 2.4170 AU |
Perihelion | 1.9593 AU |
2.1881 AU | |
Eccentricity | 0.1046 |
3.24 yr (1,182 days) | |
240.21 ° | |
Inclination | 0.7301° |
127.86° | |
308.86° | |
Physical characteristics | |
Dimensions | 6.394±0.091
[4] 6.566±0.063 km [5] 8.18 km (calculated) [3] |
9.976
h
[6] 19.2 h [7] | |
0.20 (assumed)
[3] 0.2154±0.0284 [5] 0.227±0.017 [4] | |
LS [8] · S [3] | |
12.22±0.25 [8] · 12.8 [1] [3] · 13.2 [5] | |
1720 Niels, provisional designation 1935 CQ, is a stony asteroid from the inner regions of the asteroid belt, approximately 6.4 kilometers in diameter. It was discovered on 7 February 1935, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after a grandson of the discoverer. [2] [9]
Niels orbits the Sun in the inner main-belt at a distance of 2.0–2.4 AU once every 3 years and 3 months (1,182 days). Its orbit has an eccentricity of 0.10 and an inclination of 1 ° with respect to the ecliptic. [1] First observed at Heidelberg in 1927, Niels' observation arc begins with its official discovery observation in 1935. [9]
Pan-STARRS classifies this stony asteroid as a LS-type, an intermediate to the rare L-type asteroids. [8]
A rotational lightcurve of Niels was obtained by astronomer Maurice Clark in December 2005. It gave it a rotation period of 9.976 hours with a brightness variation of 0.15 magnitude ( U=1). In November 2008, photometric observations by amateur astronomer Pierre Antonini gave another period of 19.2 hours with an amplitude of 0.01 ( U=1-). As of 2017, a secure period for Niels has not yet been obtained.
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Niels measures 6.394 kilometers in diameter, and its surface has an albedo of 0.227, [4] superseding a preliminary result that gave a slightly larger diameter and lower albedo. [5] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 8.18 kilometers based on an absolute magnitude of 12.8. [3]
The minor planet was named by the discoverer after his grandson, Niels. Reinmuth also named 1719 Jens after one of his grandsons. [2] The official naming citation was published by the Minor Planet Center on 20 February 1976 ( M.P.C. 3933). [10]
Discovery [1] | |
---|---|
Discovered by | K. Reinmuth |
Discovery site | Heidelberg Obs. |
Discovery date | 7 February 1935 |
Designations | |
(1720) Niels | |
Named after | Niels (discoverer's grandson) [2] |
1935 CQ · 1940 WH 1951 AL · 1953 VO1 1959 RA · 1963 WE | |
main-belt · ( inner) [3] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 ( JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 89.52 yr (32,697 days) |
Aphelion | 2.4170 AU |
Perihelion | 1.9593 AU |
2.1881 AU | |
Eccentricity | 0.1046 |
3.24 yr (1,182 days) | |
240.21 ° | |
Inclination | 0.7301° |
127.86° | |
308.86° | |
Physical characteristics | |
Dimensions | 6.394±0.091
[4] 6.566±0.063 km [5] 8.18 km (calculated) [3] |
9.976
h
[6] 19.2 h [7] | |
0.20 (assumed)
[3] 0.2154±0.0284 [5] 0.227±0.017 [4] | |
LS [8] · S [3] | |
12.22±0.25 [8] · 12.8 [1] [3] · 13.2 [5] | |
1720 Niels, provisional designation 1935 CQ, is a stony asteroid from the inner regions of the asteroid belt, approximately 6.4 kilometers in diameter. It was discovered on 7 February 1935, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after a grandson of the discoverer. [2] [9]
Niels orbits the Sun in the inner main-belt at a distance of 2.0–2.4 AU once every 3 years and 3 months (1,182 days). Its orbit has an eccentricity of 0.10 and an inclination of 1 ° with respect to the ecliptic. [1] First observed at Heidelberg in 1927, Niels' observation arc begins with its official discovery observation in 1935. [9]
Pan-STARRS classifies this stony asteroid as a LS-type, an intermediate to the rare L-type asteroids. [8]
A rotational lightcurve of Niels was obtained by astronomer Maurice Clark in December 2005. It gave it a rotation period of 9.976 hours with a brightness variation of 0.15 magnitude ( U=1). In November 2008, photometric observations by amateur astronomer Pierre Antonini gave another period of 19.2 hours with an amplitude of 0.01 ( U=1-). As of 2017, a secure period for Niels has not yet been obtained.
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Niels measures 6.394 kilometers in diameter, and its surface has an albedo of 0.227, [4] superseding a preliminary result that gave a slightly larger diameter and lower albedo. [5] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 8.18 kilometers based on an absolute magnitude of 12.8. [3]
The minor planet was named by the discoverer after his grandson, Niels. Reinmuth also named 1719 Jens after one of his grandsons. [2] The official naming citation was published by the Minor Planet Center on 20 February 1976 ( M.P.C. 3933). [10]