سیارک ۲۲۱

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

(221) Eos

Orbit class

Main-belt

Semi-major axis

3.012 AU

Eccentricity

0.101

Inclination

10.891 °

Absolute magnitude

7.710 H

via Minor Planet Center

Key facts

Discovered by

Johann Palisa

Discovery date

18 January 1882

Pronunciation

/ ˈ iː ɒ s /

Named after

Eos

Alternative designations

A882 BA

Minor planet category

Main belt ( Eos )

Adjectives

Eoan / iː ˈ oʊ . ən /

Observation arc

130.21 yr (47561 d)

Aphelion

3.3249 AU (497.40 Gm )

Perihelion

2.69594 AU (403.307 Gm)

Semi major axis

3.01044 AU (450.355 Gm)

Orbital period sidereal

5.22 yr (1907.8 d )

Average orbital speed

17.16 km/s

Mean anomaly

66.5202 °

Mean motion

0° 11 19.284 / day

Inclination

10.880°

Longitude of ascending node

141.845°

Argument of perihelion

193.56°

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Named after

Eos

Followed by

222 Lucia

Follows

220 Stephania

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

95.469

Orbital period

1909.822274076149

via Wikidata · CC0