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
- 22 September 1919
- Named after
- Nicholas T. Bobrovnikoff , (Russian-born astronomer)
- Alternative designations
- A919 SB · 1953 TL, 1963 RB · 1976 JB 7 , 1980 TN 3
- Minor planet category
- main-belt · ( inner ) , background
- Observation arc
- 98.35 yr (35,922 d)
- Aphelion
- 2.7846 AU
- Perihelion
- 1.7257 AU
- Semi major axis
- 2.2551 AU
- Orbital period sidereal
- 3.39 yr (1,237 d)
- Mean anomaly
- 41.979 °
- Mean motion
- 0° 17 27.6 / day
- Inclination
- 4.9312°
- Longitude of ascending node
- 356.13°
- Argument of perihelion
- 343.65°
- Mean diameter
- 5.82 ± 0.95 km , 5.97 ± 1.05 km , 6.21 ± 0.10 km , 6.919 ± 0.094 km , 7.46 km (calculated)
- Synodic rotation period
- 4.7939 ± 0.0003 h
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Followed by
- 2638 Gadolin
- Follows
- 2636 Lassell
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 6.215
- Orbital period
- 1237.231896181099
Show 17 more facts
- discoverer or inventor
- Karl Wilhelm Reinmuth
- site of astronomical discovery
- Heidelberg-Königstuhl State Observatory
- provisional designation
- A919 SB
- time of discovery or invention
- 1919-09-22
- orbital eccentricity
- 0.2352611342543326
- orbital inclination
- 4.932561381713169
- periapsis
- 1.724837887010182
- apoapsis
- 2.786082021129596
- semi-major axis of an orbit
- 2.255459954069889
- mean anomaly
- 136.7979428057125
- longitude of ascending node
- 356.0101960488577
- argument of periapsis
- 343.7935851125048
- absolute magnitude
- 13.22
- albedo
- 0.316
- rotation period
- 4.7939
- time of periapsis
- 2460530.3589495244
- epoch
- November 21, 2025
Sources (2)
via Wikidata · CC0
~3 min read
Encyclopedic overview
2637 Bobrovnikoff, provisional designation A919 SB, is a background asteroid from the inner regions of the asteroid belt, approximately 6 kilometers (4 miles) in diameter. It was discovered on 22 September 1919, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in Heidelberg, Germany. The presumed spherical S-type asteroid has a rotation period of 4.79 hours. It is named after astronomer Nicholas Bobrovnikoff, who was the director of the Perkins Observatory in Ohio, United States.
Orbit and classification
Excerpted from Wikipedia’s “2637 Bobrovnikoff” article, available under the CC BY-SA 4.0 licence.