Discovery [1] | |
---|---|
Discovered by | K. Reinmuth |
Discovery site | Heidelberg Obs. |
Discovery date | 28 September 1924 |
Designations | |
(1302) Werra | |
Named after |
Werra
[2] ( river in central Germany) |
1924 SV · 1930 WD | |
main-belt · (
outer) Themis [3] [4] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 ( JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 93.10 yr (34,003 days) |
Aphelion | 3.6580 AU |
Perihelion | 2.5677 AU |
3.1128 AU | |
Eccentricity | 0.1751 |
5.49 yr (2,006 days) | |
251.95 ° | |
0° 10m 46.2s / day | |
Inclination | 2.5958° |
90.142° | |
354.64° | |
Physical characteristics | |
Dimensions | 24.35±6.54 km
[5] 31.04 km (calculated) [3] 32.18±0.50 km [6] 34.542±0.258 km [7] 35.041±0.114 km [8] |
48 h (retracted) [9] | |
0.0710±0.0158
[7] 0.076±0.006 [8] 0.08 (assumed) [3] 0.10±0.07 [5] 0.102±0.004 [6] | |
C (assumed) [3] | |
10.60 [6] · 10.8 [7] · 10.90 [1] [3] [5] · 10.99±0.27 [10] | |
1302 Werra, provisional designation 1924 SV, is a Themistian asteroid from the outer regions of the asteroid belt, approximately 30 kilometers in diameter. It was discovered on 28 September 1924, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory. [11] The asteroid was named for the river Werra in central Germany. [2]
Werra is a Themistian asteroid that belongs to the Themis family ( 602), [3] [4] a very large family of carbonaceous asteroids, named after its parent body 24 Themis. [12]
It orbits the Sun in the outer main-belt at a distance of 2.6–3.7 AU once every 5 years and 6 months (2,006 days; semi-major axis of 3.11 AU). Its orbit has an eccentricity of 0.18 and an inclination of 3 ° with respect to the ecliptic. [1] The body's observation arc begins at Heidelberg with its official discovery observation in September 1924. [11]
Werra is an assumed carbonaceous C-type asteroid, [3] which is the overall spectral type for members of the Themis family. [12]: 23
In March 2009, a fragmentary lightcurve of Werra was obtained from photometric observations by French amateur astronomer Pierre Antonini. Lightcurve analysis gave a poorly constraint rotation period of 2 days with a brightness amplitude of less than 0.1 magnitude. [9] The result was later retracted at the Lightcurve Data Base ( U=n.a.). As of 2017, no secure period has been obtained. [3]
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Werra measures between 24.35 and 35.041 kilometers in diameter and its surface has an albedo between 0.0710 and 0.102. [5] [6] [7] [8]
The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.08 and calculates a diameter of 31.04 kilometers based on an absolute magnitude of 10.9. [3]
This minor planet was named after the river Werra in central Germany. It merges the Fulda in Hannoversch-Münden, Lower Saxony, to form the river Weser. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 ( H 119). [2]