The Phocaea family ( ; adj. ''Phocaean''; ) is a collisional

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

asteroids 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. ...

located between 2.25 and 2.5 AU in the inner region of the

asteroid belt The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...

. Phocaea asteroids are of stony S-type composition and have orbits with eccentricities greater than 0.1 and

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

s between 18 and 32 °. The family has an estimated age of 2.2 billion years and derives its name from its most massive member,

25 Phocaea Phocaea (minor planet designation: 25 Phocaea) is a stony asteroid from the inner regions of the asteroid belt, approximately 75 kilometers in diameter. It is the parent body of the Phocaea family. Discovered by Jean Chacornac in 1853, it was n ...

which is about 75 km in diameter. Several Phocaean asteroids are also

Mars-crosser A Mars-crossing asteroid (MCA, also Mars-crosser, MC) is an asteroid whose orbit crosses that of Mars. Some Mars-crossers numbered below 100000 are listed here. They include the two numbered Mars trojans 5261 Eureka and . Many databases, for i ...

Phocaea family region

The Phocaea family region contains other collisional families such as the recently identified

carbonaceous Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up ...

, Tamara family, named after its potentially largest member 326 Tamara. The family has an estimated age of 264 million years. Several clumps around 290 Bruna (Bruna family), 1192 Prisma and

6246 Komurotoru 6 (six) is the natural number following 5 and preceding 7. It is a composite number and the smallest perfect number. In mathematics Six is the smallest positive integer which is neither a square number nor a prime number; it is the second small ...

, as well as , and have also been detected.

Members

References

{{Small Solar System bodies * Asteroid groups and families