209 Dido

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

C. H. F. Peters

Discovery date

22 October 1879

Pronunciation

/ ˈ d aɪ d oʊ /

Named after

Dido

Alternative designations

A879 UC, 1909 AB, 1909 GB, 1912 RB

Minor planet category

Main belt

Adjectives

Didonian / d aɪ ˈ d oʊ n i ə n /

Observation arc

136.47 yr (49,845 d)

Aphelion

3.331 AU (498.3 Gm )

Perihelion

2.968 AU (444.1 Gm)

Semi major axis

3.150 AU (471.2 Gm)

Orbital period sidereal

5.59 yr (2,040.5 d)

Average orbital speed

16.79 km/s

Mean anomaly

311.722°

Mean motion

0° 10 34.738 / day

Inclination

7.16997°

Longitude of ascending node

0.682681°

Argument of perihelion

248.387°

via Wikipedia infobox

Wikidata facts

Diameter

179.008

Orbital period

2042.165856908191

Image

000209-asteroid shape model (209) Dido.png

via Wikidata · CC0