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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
- 8 February 1927
- Pronunciation
- / æ s t r oʊ ˈ n oʊ m i ə /
- Named after
- astronomy , (a natural science )
- Alternative designations
- 1927 CB · A911 RA
- Minor planet category
- main-belt · ( outer ) , background
- Observation arc
- 105.83 yr (38,656 days)
- Aphelion
- 3.6308 AU
- Perihelion
- 3.1511 AU
- Semi major axis
- 3.3910 AU
- Orbital period sidereal
- 6.24 yr (2,281 days)
- Mean anomaly
- 22.461 °
- Mean motion
- 0° 9 28.08 / day
- Inclination
- 4.5323°
- Longitude of ascending node
- 82.512°
- Argument of perihelion
- 203.85°
- Dimensions
- 55.4 ± 5.5 km , 55.715 ± 0.500 km , 57.253 ± 0.339 km , 59 ± 6 km , 59.68 ± 18.01 km , 60.10 ± 16.38 km , 61.08 km (SIMPS) , 64.20 ± 1.11 km
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- astronomy
- Followed by
- 1155 Aënna
- Follows
- 1153 Wallenbergia
- Parent body
- Sun
- Diameter
- 55.715
- Orbital period
- 2281.472803608413
Show 19 more facts
- discoverer or inventor
- Karl Wilhelm Reinmuth
- site of astronomical discovery
- Heidelberg-Königstuhl State Observatory
- provisional designation
- A911 RA
- time of discovery or invention
- 1927-02-08
- orbital eccentricity
- 0.06931701996173478
- albedo
- 0.036
- orbital inclination
- 4.531997045956821
- periapsis
- 3.156552507287788
- apoapsis
- 3.62675088385837
- semi-major axis of an orbit
- 3.391651695573079
- mean anomaly
- 133.7294315760948
- longitude of ascending node
- 82.48193200725453
- argument of periapsis
- 205.9321743026291
- absolute magnitude
- 10.54
- Commons category
- 1154 Astronomia
- rotation period
- 18.1154
- asteroid spectral type
- F-type asteroid
- time of periapsis
- 2460152.9998300476
- epoch
- November 21, 2025
Sources (3)
via Wikidata · CC0
~3 min read
Encyclopedic overview
1154 Astronomia, provisional designation 1927 CB, is a carbonaceous background asteroid from the outer regions of the asteroid belt, approximately 60 kilometers in diameter. It was discovered by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory on 8 February 1927. The asteroid was named for the natural science of astronomy.
Orbit and classification
Excerpted from Wikipedia’s “1154 Astronomia” article, available under the CC BY-SA 4.0 licence.