685 Hermia

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

W. Lorenz

Discovery site

Heidelberg Obs.

Discovery date

12 August 1909

Alternative designations

1909 HE

Observation arc

89.52 yr (32696 d)

Aphelion

2.6752 AU (400.20 Gm )

Perihelion

1.7969 AU (268.81 Gm)

Semi major axis

2.2360 AU (334.50 Gm)

Orbital period sidereal

3.34 yr (1221.3 d )

Mean anomaly

4.11590 °

Mean motion

0° 17 41.208 / day

Inclination

3.6466°

Longitude of ascending node

235.210°

Argument of perihelion

80.876°

Mean radius

5.475 ± 0.45 km

Synodic rotation period

50.40 ± 0.05 h (2.1000 ± 0.0021 d )

Geometric albedo

0.2807 ± 0.050

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Followed by

Q156493

Follows

Q156483

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

10.95

Orbital period

1220.839441785459

Image

685Hermia (Lightcurve Inversion).png

via Wikidata · CC0