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EntityQ155725· pop 37· linked from 8 articles

Also known as (591) Irmgard, Irmgard

main-belt asteroid

Picture of the Day · NASA

Pathfinder on Mars

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
August Kopff
Discovery site
Heidelberg
Discovery date
14 March 1906
Pronunciation
German: [ ˈɪʁmɡaːt ]
Alternative designations
1906 TP
Observation arc
110.08 yr (40205 d)
Aphelion
3.2342 AU (483.83 Gm )
Perihelion
2.1241 AU (317.76 Gm)
Semi major axis
2.6792 AU (400.80 Gm)
Orbital period sidereal
4.39 yr (1601.8 d )
Mean anomaly
43.3627 °
Mean motion
0° 13 29.1 / day
Inclination
12.490°
Longitude of ascending node
334.289°
Argument of perihelion
217.191°
Mean radius
25.93 ± 0.65 km
Synodic rotation period
7.35 h (0.306 d )
Geometric albedo
0.0364 ± 0.002

via Wikipedia infobox

Wikidata facts

Instance of
asteroid
Followed by
Q155728
Parent body
Sun
Minor-planet group
asteroid belt
Diameter
51.86
Orbital period
1600.678013720135
Show 18 more facts
discoverer or inventor
August Kopff
site of astronomical discovery
Heidelberg-Königstuhl State Observatory
provisional designation
1955 ML1
time of discovery or invention
1906-03-14
orbital inclination
12.45130730419834
albedo
0.0364
rotation period
7.35
asteroid spectral type
X-type asteroid
absolute magnitude
10.63
orbital eccentricity
0.2100299823314297
semi-major axis of an orbit
2.677957632761312
periapsis
2.115506238468137
apoapsis
3.240409027054488
longitude of ascending node
334.0700552857927
argument of periapsis
218.8342459179462
mean anomaly
85.47352860354349
time of periapsis
2460620.456672248
Sources (3)

via Wikidata · CC0

~1 min read

Encyclopedic overview

591 Irmgard is a minor planet orbiting the Sun.

References

Excerpted from Wikipedia’s “Q155725” article, available under the CC BY-SA 4.0 licence.