
File:001023-asteroid_shape_model_(1023)_Thomana.png · Wikimedia Commons · See Wikimedia Commons
Picture of the Day · NASA

Pathfinder on Mars
2026-07-04
On July 4th, 1997, using its own array of fireworks, a parachute, and a cocoon of airbags, the Mars Pathfinder spacecraft bounced like a giant beach ball at least 15 times before it came to rest on the surface of Mars at 10:07 AM Pacific Daylight Time. After its then novel airbag-assisted landing sequence was completed, Pathfinder transmitted this color mosaic to mission operators on Earth. In the scene from another world, the Mars Sojourner robot rover is visible in the foreground, crouched on top of the unfolded Pathfinder. About the size of a large house cat, the six-wheeled, solar-powered Sojourner became the first successful Martian rover. Surrounding Pathfinder are deflated airbags and the rock-strewn terrain of the Ares Vallis floodplain. In the distance Martian hills appear against a dusty brownish sky. The Pathfinder lander was subsequently renamed the Carl Sagan Memorial Station.
via NASA APOD
Key facts
- Discovered by
- K. Reinmuth
- Discovery site
- Heidelberg Obs.
- Discovery date
- 25 June 1924
- Named after
- St. Thomas Choir of Leipzig , (German boys' choir )
- Alternative designations
- 1924 RU · 1936 RG
- Minor planet category
- main-belt · ( outer )
- Observation arc
- 92.86 yr (33,916 days)
- Aphelion
- 3.4893 AU
- Perihelion
- 2.8442 AU
- Semi major axis
- 3.1667 AU
- Orbital period sidereal
- 5.64 yr (2,058 days)
- Mean anomaly
- 107.00 °
- Mean motion
- 0° 10 29.64 / day
- Inclination
- 10.078°
- Longitude of ascending node
- 194.32°
- Argument of perihelion
- 194.19°
- Dimensions
- 53.28 ± 20.25 km , 58.27 ± 1.6 km ( IRAS :11) , 61.02 ± 1.00 km , 61.34 ± 4.17 km
- Synodic rotation period
- 17.56 ± 0.05 h , 17.56 ± 0.01 h , 17.561 ± 0.007 h , 17.5611 ± 0.0005 h
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Followed by
- Q757151
- Follows
- Q11565
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 58.27
- Orbital period
- 2063.822897905509
- Image
- 001023-asteroid shape model (1023) Thomana.png
Show 18 more facts
- discoverer or inventor
- Karl Wilhelm Reinmuth
- site of astronomical discovery
- Heidelberg-Königstuhl State Observatory
- provisional designation
- A924 MC
- time of discovery or invention
- 1924-06-25
- orbital eccentricity
- 0.09568407015081946
- albedo
- 0.0649
- orbital inclination
- 10.0593817559816
- periapsis
- 2.868817012440176
- apoapsis
- 3.475905927293131
- semi-major axis of an orbit
- 3.172361469866654
- mean anomaly
- 268.8046833329242
- longitude of ascending node
- 193.895344323457
- argument of periapsis
- 196.2023810882917
- absolute magnitude
- 10.16
- rotation period
- 17.56
- asteroid spectral type
- G-type asteroid
- time of periapsis
- 2461523.3082853314
- epoch
- November 21, 2025
Sources (3)
via Wikidata · CC0
~3 min read
Encyclopedic overview
1023 Thomana, provisional designation 1924 RU, is a rare-type carbonaceous background asteroid from the outer regions of the asteroid belt, approximately 58 kilometers in diameter. It was discovered on 25 June 1924, by German astronomer Karl Reinmuth at Heidelberg Observatory in southwest Germany. The asteroid was named after the St. Thomas Choir of Leipzig.
Classification and orbit
Excerpted from Wikipedia’s “Q118370” article, available under the CC BY-SA 4.0 licence.