578 Happelia

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

578 Happelia (A905 VJ)

Orbit class

Main-belt Asteroid

Diameter

69.290 km

Albedo

0.077

Rotation period

10.061 h

Absolute magnitude

9.540 H

Earth MOID

1.210 AU

via NASA/JPL Small-Body Database

Key facts

Discovered by

M. F. Wolf

Discovery site

Heidelberg

Discovery date

1 November 1905

Alternative designations

1905 RZ

Observation arc

110.46 yr (40344 d)

Aphelion

3.2821 AU (491.00 Gm )

Perihelion

2.2168 AU (331.63 Gm)

Semi major axis

2.7494 AU (411.30 Gm)

Orbital period sidereal

4.56 yr (1665.2 d )

Mean anomaly

200.53 °

Mean motion

0° 12 58.284 / day

Inclination

6.1525°

Longitude of ascending node

29.411°

Argument of perihelion

261.400°

Mean radius

34.645 ± 1.05 km

Synodic rotation period

10.061 h (0.4192 d )

Geometric albedo

0.0769 ± 0.005

via Wikipedia infobox