File:24_Themis_VLT_(2021),_deconvolved.pdf · 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
Small body data
(24) Themis
- Orbit class
- Main-belt
- Semi-major axis
- 3.144 AU
- Eccentricity
- 0.115
- Inclination
- 0.737 °
- Absolute magnitude
- 7.210 H
via Minor Planet Center
Key facts
- Discovered by
- Annibale de Gasparis
- Discovery date
- 5 April 1853
- Pronunciation
- / ˈ θ iː m ɪ s /
- Named after
- Themis
- Alternative designations
- 1947 BA; 1955 OH
- Minor planet category
- Main belt ( Themis )
- Adjectives
- Themistian / θ ɪ ˈ m ɪ s t i ə n /
- Aphelion
- 524.4 Gm , (3.505 AU )
- Perihelion
- 415.9 million km, (2.780 AU)
- Semi major axis
- 470.2 million km, (3.143 AU)
- Orbital period sidereal
- 2035 d (5.57 yr )
- Mean anomaly
- 346.1°
- Inclination
- 0.7368°
- Longitude of ascending node
- 36.39°
- Argument of perihelion
- 109.0°
- Earth moid
- 1.79422 AU
- Jupiter moid
- 1.50402 AU
- Dimensions
- 232 × 220 × 176 ± 14 km
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Themis
- Followed by
- 25 Phocaea
- Follows
- 23 Thalia
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 198.0
- Mass
- 23
- Orbital period
- 2035.483941708615
- Image
- A609.M1006.shape.png
Show 19 more facts
- discoverer or inventor
- Annibale de Gasparis
- site of astronomical discovery
- Astronomical Observatory of Capodimonte
- provisional designation
- A853 GA
- time of discovery or invention
- 1853-04-05
- asteroid spectral type
- B-type asteroid
- orbital inclination
- 0.7366995185411344
- albedo
- 0.067
- Commons category
- 24 Themis
- rotation period
- 8.374
- absolute magnitude
- 7.22
- orbital eccentricity
- 0.1153430068927704
- semi-major axis of an orbit
- 3.143254184754319
- periapsis
- 2.780701795656472
- apoapsis
- 3.505806573852166
- longitude of ascending node
- 36.39222831043986
- argument of periapsis
- 109.1075227534647
- mean anomaly
- 56.76452096312276
- time of periapsis
- 2460679.54646978
- epoch
- November 21, 2025
via Wikidata · CC0
~4 min read
Encyclopedic overview
24 Themis is one of the largest asteroids in the asteroid belt. At roughly 200 kilometres (120 mi) in diameter, it is also the largest member of the Themistian family. It was discovered by Annibale de Gasparis on 5 April 1853. It is named after Themis, the personification of natural law and divine order in Greek mythology.
Discovery and observations
Excerpted from Wikipedia’s “24 Themis” article, available under the CC BY-SA 4.0 licence.