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EntityQ156051· pop 40· linked from 8 articles

Also known as (638) Moira, Moira

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
Joel Hastings Metcalf
Discovery site
Taunton, Massachusetts
Discovery date
5 May 1907
Pronunciation
/ ˈ m ɔɪ r ə /
Named after
Moirae
Alternative designations
1907 ZQ
Observation arc
110.22 yr (40257 d)
Aphelion
3.1701 AU (474.24 Gm )
Perihelion
2.3005 AU (344.15 Gm)
Semi major axis
2.7353 AU (409.20 Gm)
Orbital period sidereal
4.52 yr (1652.4 d )
Mean anomaly
54.7967 °
Mean motion
0° 13 4.332 / day
Inclination
7.7123°
Longitude of ascending node
103.208°
Argument of perihelion
128.586°
Mean radius
32.72 ± 0.7 km
Synodic rotation period
9.875 h (0.4115 d )

via Wikipedia infobox

~1 min read

Encyclopedic overview

638 Moira, also known as A907 JG, is a minor planet orbiting the Sun. First observed in 1906, 638 Moira was discovered to be an orbital body in 1907 by Joel Hastings Metcalf in Taunton, England. 638 Moira is a little over 59.5 km across and rotates once every 10 hours. Its farthest point from the sun is a little over 3au during its 4.5 year orbit, and it is classed as an L-type asteroid (SMASSII).

References

Excerpted from Wikipedia’s “Q156051” article, available under the CC BY-SA 4.0 licence.