584 Semiramis

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

A. Kopff

Discovery site

Heidelberg

Discovery date

15 January 1906

Pronunciation

/ s ɪ ˈ m ɪr ə m ɪ s /

Named after

Semiramis

Alternative designations

1906 SY

Observation arc

110.26 yr (40272 d)

Aphelion

2.9282 AU (438.05 Gm )

Perihelion

1.8224 AU (272.63 Gm)

Semi major axis

2.3753 AU (355.34 Gm)

Orbital period sidereal

3.66 yr (1337.1 d )

Mean anomaly

166.35 °

Mean motion

0° 16 9.228 / day

Inclination

10.718°

Longitude of ascending node

282.159°

Argument of perihelion

85.121°

Mean radius

27.005 ± 0.7 km , 25.89 ± 1.075 km

Mass

(8.23 ± 5.77) × 10 kg

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Named after

Semiramis

Followed by

585 Bilkis

Follows

583 Klotilde

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

54.01

Orbital period

1335.849001124177

Image

584Semiramis (Lightcurve Inversion).png

via Wikidata · CC0