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EntityQ138810· pop 36· linked from 152 articles

Also known as Ajax

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
K. Reinmuth
Discovery site
Heidelberg Obs.
Discovery date
17 August 1936
Pronunciation
/ ˈ eɪ dʒ æ k s /
Named after
Ajax (Greek mythology)
Alternative designations
1936 QW
Minor planet category
Jupiter trojan , Greek · background
Adjectives
Ajantian / ə ˈ dʒ æ n t i ə n /
Observation arc
81.76 yr (29,864 d)
Aphelion
5.9044 AU
Perihelion
4.6992 AU
Semi major axis
5.3018 AU
Orbital period sidereal
12.21 yr (4,459 d)
Mean anomaly
247.16 °
Mean motion
0° 4 50.52 / day
Inclination
18.005°
Longitude of ascending node
332.92°
Argument of perihelion
59.772°

via Wikipedia infobox

Wikidata facts

Instance of
asteroid
Named after
Ajax the Great
Followed by
1405 Sibelius
Follows
Q138797
Parent body
Sun
Minor-planet group
asteroid belt
Diameter
83.99
Orbital period
4435.52638672312
Image
001404-asteroid shape model (1404) Ajax.png
Show 18 more facts
discoverer or inventor
Karl Wilhelm Reinmuth
site of astronomical discovery
Heidelberg-Königstuhl State Observatory
provisional designation
1936 QW
time of discovery or invention
1936-08-17
orbital eccentricity
0.1124052870928298
albedo
0.048
orbital inclination
18.03163071086053
periapsis
4.689348758553304
apoapsis
5.877070104384973
semi-major axis of an orbit
5.283209431469139
mean anomaly
112.570143838859
longitude of ascending node
332.8772857573175
argument of periapsis
61.74117568804254
absolute magnitude
9.29
Commons category
1404 Ajax
rotation period
29.411
time of periapsis
2459613.5337684597
Sources (3)

via Wikidata · CC0

~4 min read

Encyclopedic overview

1404 Ajax /ˈeɪdʒæks/ is a carbonaceous Jupiter trojan from the Greek camp, approximately 83 kilometers (52 miles) kilometers in diameter. It was discovered on 17 August 1936, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after the legendary warrior Ajax from Greek mythology. The assumed C-type asteroid belongs to the 40 largest Jupiter trojans and has a longer than average rotation period of 29.4 hours.

Orbit and classification

Excerpted from Wikipedia’s “Q138810” article, available under the CC BY-SA 4.0 licence.