1045 Michela

1045 Michela
Discovery
Discovered byG. van Biesbroeck
Discovery siteYerkes Obs.
Discovery date19 November 1924
Designations
Named after
Micheline van Biesbroeck
(discoverer's daughter)
1924 TR · 1953 VB2
1964 XJ · 1976 AL
main-belt · (inner)
Massalia
Orbital characteristics
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc63.64 yr (23,246 d)
Aphelion2.7348 AU
Perihelion1.9811 AU
2.3580 AU
Eccentricity0.1598
3.62 yr (1,323 d)
259.96°
0° 16m 19.92s / day
Inclination0.2648°
267.71°
166.97°
Known satellites1
Physical characteristics
6.104±0.265 km
0.328±0.077
SMASS = S
13.0

1045 Michela, provisional designation 1924 TR, is an stony, binary, Massalian asteroid from the inner regions of the asteroid belt, approximately 6 kilometers (4 miles) in diameter. It was discovered on 19 November 1924, by Belgian–American astronomer George Van Biesbroeck at the Yerkes Observatory in Williams Bay, Wisconsin, United States. The S-type asteroid was named after the discoverer's daughter, Micheline van Biesbroeck.

Orbit and classification

Michela is a member of the Massalia family (404), a very large inner belt asteroid family consisting of stony asteroids. It orbits the Sun in the inner main-belt at a distance of 2.0–2.7 AU once every 3 years and 7 months (1,323 days; semi-major axis of 2.36 AU). Its orbit has an eccentricity of 0.16 and an inclination of 0° with respect to the ecliptic.

The asteroid's observation arc begins with its observation as 1953 VB2 at the Goethe Link Observatory in November 1953, or 29 years after its official discovery observation.

Physical characteristics

In the SMASS classification, Michela is a common, stony S-type asteroid, which is also the overall spectral type for Massalian asteroids.: 23 

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Michela measures 6.104 kilometers in diameter and its surface has an albedo of 0.328.

Rotation period

As of 2018, no rotational lightcurve of Michela has been obtained from photometric observations. The body's rotation period, poles and shape remain unknown.

Satellite

On 9 October 2025, a team of astronomers including D. Gault, D. Herald, C. McPartlin, and C. Weber, discovered a natural satellite orbiting Michela from occultation observations from Goleta, California. The orbital period of this moon is estimated to be 2.2 days, with a diameter of less than 2.2 kilometers. As of 2026, the moon of Michela remains unnamed and undesignated.

Naming

This minor planet was named after Micheline van Biesbroeck, daughter of the discoverer George Van Biesbroeck. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 99).

References

  1. 1 2 3 4 "1045 Michela (1924 TR)". Minor Planet Center. Retrieved 20 March 2018.
  2. 1 2 3 Schmadel, Lutz D. (2007). "(1045) Michela". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 89. doi:10.1007/978-3-540-29925-7_1046. ISBN 978-3-540-00238-3.
  3. 1 2 3 4 5 6 7 "JPL Small-Body Database Browser: 1045 Michela (1924 TR)" (2017-07-04 last obs.). Jet Propulsion Laboratory. Retrieved 20 March 2018.
  4. 1 2 "Asteroid 1045 Michela – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Archived from the original on 3 October 2020. Retrieved 24 October 2019.
  5. 1 2 3 Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 20 March 2018.
  6. 1 2 Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families". Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 978-0-8165-3213-1.
  7. ↑ "(1045) Michela". www.johnstonsarchive.net. Retrieved 25 August 2026.