File:98Ianthe_(Lightcurve_Inversion).png · Wikimedia Commons · See Wikimedia Commons
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
Small body data
98 Ianthe (A868 HA)
- Orbit class
- Main-belt Asteroid
- Diameter
- 132.788 km
- Albedo
- 0.029
- Rotation period
- 16.479 h
- Absolute magnitude
- 8.950 H
- Earth MOID
- 1.200 AU
via NASA/JPL Small-Body Database
Key facts
- Discovered by
- Christian Heinrich Friedrich Peters
- Discovery date
- 18 April 1868
- Pronunciation
- / aɪ ˈ æ n θ iː /
- Named after
- Ianthe
- Minor planet category
- Main belt
- Adjectives
- Ianthean / aɪ ə n ˈ θ iː ə n /
- Observation arc
- 145.23 yr (53047 d)
- Aphelion
- 3.18807 AU (476.928 Gm )
- Perihelion
- 2.18872 AU (327.428 Gm)
- Semi major axis
- 2.68839 AU (402.177 Gm)
- Orbital period sidereal
- 4.41 yr (1610.0 d )
- Average orbital speed
- 18.01 km/s
- Mean anomaly
- 262.019 °
- Mean motion
- 0° 13 24.949 / day
- Inclination
- 15.5778°
- Longitude of ascending node
- 354.000°
- Argument of perihelion
- 158.686°
- Earth moid
- 1.20327 AU (180.007 Gm)
via Wikipedia infobox
Wikidata facts
- Diameter
- 132.788
- Orbital period
- 1609.046799963197
- Image
- 98Ianthe (Lightcurve Inversion).png
Show 15 more facts
- provisional designation
- A868 HA
- time of discovery or invention
- 1868-04-18
- orbital inclination
- 15.57591383219321
- albedo
- 0.029
- Commons category
- 98 Ianthe
- rotation period
- 16.479
- absolute magnitude
- 8.96
- orbital eccentricity
- 0.1878739662089167
- semi-major axis of an orbit
- 2.687283585614275
- periapsis
- 2.182412960056802
- apoapsis
- 3.192154211171747
- longitude of ascending node
- 353.8725347905175
- argument of periapsis
- 158.1595545910168
- mean anomaly
- 303.3774414884672
- time of periapsis
- 2461253.578740496
Sources (2)
via Wikidata · CC0
~1 min read
Article
98 Ianthe is a large main-belt asteroid, named for three figures in Greek mythology. It is very dark and is composed of carbonates. It was one of the numerous (for his time—the 19th century) discoveries by C. H. F. Peters, who found it on April 18, 1868, from Clinton, New York.
This body is orbiting the Sun with a period of 4.41 years and an eccentricity of 0.186. The orbital plane is inclined at an angle of 15.6° to the plane of the ecliptic. Measurements of the cross-section dimension yield a size of around 105 km. Photometric observations of this asteroid during 2007 at the Organ Mesa Observatory in Las Cruces, New Mexico were used to create a light curve plot. This showed a synodic rotation period of 16.479±0.001 hours and a brightness variation of 0.27±0.02 magnitude during each cycle. It is classified as a C-type asteroid, indicating a dark, carbonaceous surface.