The Nysa family (adj. ''Nysian'';
FIN:
405
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Year 405 ( CDV) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Stilicho and Anthemius (or, less frequently, year 1158 ''Ab ...
) is part of the Nysa–Polana complex, the largest cluster of
asteroid families
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere.
...
in the
asteroid belt.
It is located in the
inner region of the asteroid belt, orbiting the Sun between 2.41 and 2.5
AU. Asteroids in this complex have
eccentricities between 0.12 and 0.21 and
inclinations of 1.4 to 4.3. The family derives its name from its most massive member,
44 Nysa
Nysa (minor planet designation: 44 Nysa) is a large and very bright main-belt asteroid, and the brightest member of the Nysian asteroid family. It is classified as a rare class E asteroid and is probably the largest of this type (though 55 Pan ...
. It has also been known as the Hertha family ''(adj. Herthian)'' named after
135 Hertha.
Subdivision
Asteroids in this complex are typically divided into the stony Nysa and carbonaceous Polana subgroups, two mineralogically different families:
* The much brighter
S-type Nysian subgroup (i.e. the Nysa family, in the narrower sense) includes
44 Nysa and
135 Hertha
Hertha (minor planet designation: 135 Hertha) is an asteroid from the inner region of the asteroid belt, approximately in diameter. Discovered on 18 February 1874 by German–American astronomer Christian Peters at the Litchfield Observatory ne ...
.
* In the low-
albedo subgroup of the complex lies the Polana family ''(adj Polanian)'', a family of dark
F-type asteroids named after
142 Polana
Polana (minor planet designation: 142 Polana) is a very dark asteroid from the asteroid belt. It was discovered by Johann Palisa on January 28, 1875, and named after the city of Pola (now Pula, Croatia), home of the Austrian Naval Observatory w ...
, the largest asteroid in this section.
More recently an additional family, the Eulalia family has also been identified inside this subgroup.
Nysian asteroids
See also
*
101955 Bennu
101955 Bennu (provisional designation ) is a carbonaceous asteroid in the Apollo group discovered by the LINEAR Project on 11 September 1999. It is a potentially hazardous object that is listed on the Sentry Risk Table and has the highest cumula ...
, probably part of the Polana family, visited by the
OSIRIS-REx spacecraft in 2018
References
}
{{Small Solar System bodies
*