File:158Koronis_(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
Key facts
- Discovered by
- Viktor Knorre
- Discovery date
- 4 January 1876
- Pronunciation
- / k ɒ ˈ r oʊ n ɪ s /
- Alternative designations
- A876 AA; 1893 PA;, 1911 HB; 1955 HA1
- Minor planet category
- Main belt
- Adjectives
- Koronidian / k ɒr ə ˈ n ɪ d i ə n /
- Observation arc
- 122.53 yr (44755 d)
- Aphelion
- 3.0181 AU (451.50 Gm )
- Perihelion
- 2.71904 AU (406.763 Gm)
- Semi major axis
- 2.86858 AU (429.133 Gm)
- Orbital period sidereal
- 4.86 yr (1774.6 d )
- Average orbital speed
- 17.80 km/s
- Mean anomaly
- 15.346 °
- Mean motion
- 0° 12 10.296 / day
- Inclination
- 1.0015°
- Longitude of ascending node
- 277.96°
- Argument of perihelion
- 142.37°
- Earth moid
- 1.7299 AU (258.79 Gm)
via Wikipedia infobox
~2 min read
Encyclopedic overview
158 Koronis is a main-belt asteroid that was discovered by Russian astronomer Viktor Knorre on January 4, 1876, from the Berlin observatory. It was the first of his four asteroid discoveries. The meaning of the asteroid name is uncertain, but it may come from Coronis, the mother of Asclepius from Greek mythology. Alternatively, it may come from Coronis, a nymph of the Hyades sisterhood. The Koronis family is named after this asteroid.
From its spectrum this is classified as an S-type asteroid, indicating a stony composition. Photometric observations show a synodic rotation period of 14.206 ± 0.002 hours with a brightness variation of 0.28–0.43 in magnitude. A subsequent study at the Altimira Observatory during 2010 was in agreement with this estimate, yielding a rotation period of 14.208 ± 0.040 hours. Based on a model constructed from the lightcurve, the shape of Koronis resembles that of 243 Ida, an asteroid in the same family, although it is a bit larger.
Excerpted from Wikipedia’s “158 Koronis” article, available under the CC BY-SA 4.0 licence.