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
- J. Palisa
- Discovery site
- Vienna Observatory
- Discovery date
- 21 October 1911
- Pronunciation
- / h æ ˈ m oʊ n i ə /
- Named after
- Hamburg
- Alternative designations
- 1911 NB
- Observation arc
- 113.17 yr (41337 d)
- Aphelion
- 3.1540 AU (471.83 Gm )
- Perihelion
- 2.8324 AU (423.72 Gm)
- Semi major axis
- 2.9932 AU (447.78 Gm)
- Orbital period sidereal
- 5.18 yr (1891.5 d )
- Mean anomaly
- 71.167 °
- Mean motion
- 0° 11 25.188 / day
- Inclination
- 4.9954°
- Longitude of ascending node
- 163.351°
- Argument of perihelion
- 246.398°
- Mean radius
- 17.84 ± 0.7 km
- Synodic rotation period
- 5.436 h (0.2265 d )
via Wikipedia infobox
Wikidata facts
- Diameter
- 23.456
- Orbital period
- 1890.324298048589
Show 14 more facts
- provisional designation
- A911 UO
- time of discovery or invention
- 1911-10-21
- orbital inclination
- 4.991296147130802
- albedo
- 0.352
- rotation period
- 5.436
- absolute magnitude
- 10.15
- orbital eccentricity
- 0.05628799342835141
- semi-major axis of an orbit
- 2.991979360042599
- periapsis
- 2.823566845486758
- apoapsis
- 3.16039187459844
- longitude of ascending node
- 163.1574961672079
- argument of periapsis
- 251.6190647844178
- mean anomaly
- 352.8220254983256
- time of periapsis
- 2461038.1908322535
Sources (2)
via Wikidata · CC0
~1 min read
Article
723 Hammonia is a minor planet orbiting the Sun. It was discovered in 1911 and is named after the city of Hamburg. Although the name alludes to Hamburg it was discovered in Vienna.
The asteroid was discovered by the noted and prolific astronomer Johann Palisa. He worked from Pola early in his career and later from Vienna observatories. The same night he discovered Hammonia, he also discovered 724 Hapag and 725 Amanda. He discovered dozens and dozens of asteroids between 1874 and 1923, ranging from 136 Austria to 1073 Gellivara.