1229 Tilia

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

K. Reinmuth

Discovery site

Heidelberg Obs.

Discovery date

9 October 1931

Pronunciation

/ ˈ t ɪ l i ə /

Named after

Tilia ( flowering plant )

Alternative designations

1931 TP 1 · 1936 MC, 1942 PH · 1948 PT, 1951 AC · 1951 CM, 1973 YW 3 · 1975 FP, 1976 KB 1 · 1977 RC 4 , 1978 VK 4

Minor planet category

main-belt · ( outer ) , Themis

Observation arc

85.74 yr (31,318 d )

Aphelion

3.7569 AU

Perihelion

2.6918 AU

Semi major axis

3.2243 AU

Orbital period sidereal

5.79 yr (2,115 days)

Mean anomaly

283.97 °

Mean motion

0° 10 12.72 / day

Inclination

1.0392°

Longitude of ascending node

197.37°

Argument of perihelion

166.53°

Dimensions

27.795 ± 0.276 km

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Followed by

1230 Riceia

Follows

1228 Scabiosa

Parent body

Sun

Diameter

27.795

Orbital period

2118.577057502597

via Wikidata · CC0