Image by 5274654 on Pixabay · Pixabay License
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
(1535) Paijanne
- Orbit class
- Main-belt
- Semi-major axis
- 3.156 AU
- Eccentricity
- 0.202
- Inclination
- 6.083 °
- Absolute magnitude
- 11.570 H
via Minor Planet Center
Key facts
- Discovered by
- Y. Väisälä
- Discovery site
- Turku Observatory
- Discovery date
- 9 September 1939
- Pronunciation
- pæi(j)ænːe
- Named after
- Lake Päijänne (Finland)
- Alternative designations
- 1939 RC · 1933 QE 1 , 1944 OA · 1956 XB, 1985 XE 2 · A916 OB
- Minor planet category
- main-belt · ( outer )
- Observation arc
- 83.77 yr (30,598 days)
- Aphelion
- 3.7718 AU
- Perihelion
- 2.5586 AU
- Semi major axis
- 3.1652 AU
- Orbital period sidereal
- 5.63 yr (2,057 days)
- Mean anomaly
- 23.100 °
- Mean motion
- 0° 10 30 / day
- Inclination
- 6.0561°
- Longitude of ascending node
- 264.79°
- Argument of perihelion
- 39.922°
- Dimensions
- 23.836 ± 0.206 km , 25.518 ± 0.187 km , 26.12 ± 0.42 km , 26.36 km (derived) , 26.72 ± 1.0 km
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Päijänne
- Followed by
- 1536 Pielinen
- Follows
- 1534 Näsi
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 23.836
- Orbital period
- 2051.105248532001
Show 17 more facts
- discoverer or inventor
- Yrjö Väisälä
- site of astronomical discovery
- Iso-Heikkilä Observatory
- provisional designation
- A916 OB
- time of discovery or invention
- 1939-09-09
- orbital eccentricity
- 0.2003240614041096
- orbital inclination
- 6.085730798678239
- periapsis
- 2.526428672186047
- apoapsis
- 3.792202538906967
- semi-major axis of an orbit
- 3.159315605546507
- mean anomaly
- 186.6653643106498
- longitude of ascending node
- 264.5482951325956
- argument of periapsis
- 41.03790226162169
- absolute magnitude
- 11.58
- albedo
- 0.164
- rotation period
- 8.8448
- time of periapsis
- 2461988.07661393
- epoch
- November 21, 2025
Sources (3)
via Wikidata · CC0
~3 min read
Encyclopedic overview
1535 Päijänne (/pæi(j)ænːe/; provisional designation 1939 RC) is an asteroid from the outer region of the asteroid belt, approximately 25 kilometers in diameter. It was discovered on 9 September 1939, by Finnish astronomer Yrjö Väisälä at the Turku Observatory in Southwest Finland. It was later named for Lake Päijänne.
Orbit
Excerpted from Wikipedia’s “1535 Päijänne” article, available under the CC BY-SA 4.0 licence.