File:000206-asteroid_shape_model_(206)_Hersilia.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
- C. H. F. Peters
- Discovery date
- 13 October 1879
- Pronunciation
- / h ər ˈ s ɪ l i ə /
- Named after
- Hersilia
- Alternative designations
- A879 TC, 1961 WG, 1974 PM
- Minor planet category
- Main belt
- Observation arc
- 136.34 yr (49798 d)
- Aphelion
- 2.84299 AU (425.305 Gm )
- Perihelion
- 2.63811 AU (394.656 Gm)
- Semi major axis
- 2.74055 AU (409.980 Gm)
- Orbital period sidereal
- 4.54 yr (1657.1 d )
- Average orbital speed
- 17.99 km/s
- Mean anomaly
- 348.975 °
- Mean motion
- 0° 13 2.078 / day
- Inclination
- 3.77868°
- Longitude of ascending node
- 145.169°
- Argument of perihelion
- 299.705°
- Dimensions
- 113 km
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Hersilia
- Followed by
- Q147330
- Follows
- 205 Martha
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 113.0
- Orbital period
- 1658.43849445557
Show 19 more facts
- discoverer or inventor
- Christian Heinrich Friedrich Peters
- site of astronomical discovery
- Litchfield Observatory
- provisional designation
- A879 TC
- time of discovery or invention
- 1879-10-13
- asteroid spectral type
- C-type asteroid
- orbital inclination
- 3.780685768427134
- albedo
- 0.057
- Commons category
- 206 Hersilia
- rotation period
- 11.122
- absolute magnitude
- 8.94
- orbital eccentricity
- 0.04082946892258829
- semi-major axis of an orbit
- 2.741999020014442
- periapsis
- 2.630044656240995
- apoapsis
- 2.85395338378789
- longitude of ascending node
- 144.9955985089659
- argument of periapsis
- 302.099010543572
- mean anomaly
- 5.185021141950084
- time of periapsis
- 2460976.61378151
- epoch
- November 21, 2025
Sources (2)
via Wikidata · CC0
~1 min read
Encyclopedic overview
206 Hersilia is a fairly large Main belt asteroid. It was discovered by C. H. F. Peters on October 13, 1879, in Clinton, New York. The asteroid was named after Hersilia, Roman wife of Romulus. It is classified as a primitive, dark carbon-rich C-type asteroid.
Measurements made with the IRAS observatory give a diameter of 101.72 ± 5.18 km and a geometric albedo of 0.06 ± 0.01. By comparison, the MIPS photometer on the Spitzer Space Telescope gives a diameter of 97.99 ± 7.40 km and a geometric albedo of 0.06 ± 0.02.
Excerpted from Wikipedia’s “206 Hersilia” article, available under the CC BY-SA 4.0 licence.