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228 Agathe
Orbital diagram
Discovery  [1]
Discovered by J. Palisa
Discovery site Vienna Observatory
Discovery date19 August 1882
Designations
(228) Agathe
Named after
daughter of astronomer
Theodor v. Oppolzer [2]
A882 QA
main-belt
Orbital characteristics [1]
Epoch 13 September 2023
( JD 2453300.5)
Uncertainty parameter 0
Observation arc130.80 yr
Aphelion2.73  AU (408 million  km)
Perihelion1.67 AU (250 million km)
2.20 AU (329 million km)
Eccentricity0.24227
3.27 yr (1193.1 d)
63.67 °
0° 18m 6.408s / day
Inclination2.5359°
313.25°
19.177°
Earth  MOID0.657 AU (98.3 million km)
Mars  MOID0.29 AU (43 million km)
Jupiter  MOID2.63 AU (393 million km)
TJupiter3.624
Physical characteristics
Dimensions9.30±0.8  km
6.484  h (0.2702  d)
0.2082±0.043
B–V = 0.918
U–B = 0.596
S ( Tholen), S ( SMASS)
12.32

228 Agathe is a stony main belt asteroid, about 9 kilometers in diameter. It was discovered by Johann Palisa on 19 August 1882 at Vienna Observatory, Austria. Photometric observations during 2003 showed a rotation period of 6.48 ± 0.01 hours with a brightness variation of 0.27 ± 0.03 in magnitude. An earlier study yielded results that are consistent with these estimates. [3] Agathe is the lowest numbered asteroid to have an Earth- MOID as low as 0.657  AU (98.3 million  km). [1] On 23 August 2029 the asteroid will be 0.659 AU (98.6 million km) from Earth.

228 Agathe Earth approach on 23 August 2029 [4]
Date and time of
closest approach
Earth distance
( AU)
Sun distance
(AU)
Velocity
relative to Earth
(km/s)
Velocity
relative to Sun
(km/s)
Uncertainty
region
( 3-sigma)
Solar
elongation
23 August 2029 ≈07:22 0.6597  AU (98.69 million  km; 61.32 million  mi; 256.7  LD) 1.67 AU (250 million km; 155 million mi) 3.9 25.7 ± 1.4 km 177.9°

Agathe was named after the youngest daughter of Austrian astronomer Theodor von Oppolzer (1841–1886), professor of astronomy in Vienna. [2]

References

  1. ^ a b c "JPL Small-Body Database Browser: 228 Agathe" (2023-08-05 last obs.). Jet Propulsion Laboratory. Retrieved 20 September 2023.
  2. ^ a b Schmadel, Lutz D. (2003). Dictionary of Minor Planet Names – (228) Agathe. Springer Berlin Heidelberg. p. 35. doi: 10.1007/978-3-540-29925-7_229. ISBN  978-3-540-29925-7.
  3. ^ Cooney, Walter R. Jr. (March 2005), "Lightcurve results for minor planets 228 Agathe, 297 Caecilia, 744 Aguntina 1062 Ljuba, 1605 Milankovitch, and 3125 Hay", The Minor Planet Bulletin, 32 (1): 15–16, Bibcode: 2005MPBu...32...15C.
  4. ^ "Horizons Batch for 228 Agathe on 2029-Aug-23" (Closest Earth approach occurs when deldot flips from negative to positive). JPL Horizons. Retrieved 20 September 2023.