Unitas (

minor planet designation A formal minor-planet designation is, in its final form, a number–name combination given to a minor planet (asteroid, centaur, trans-Neptunian object and dwarf planet but not comet). Such designation always features a leading number (catalog or ...

: 306 Unitas) is a typical

main 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 ...

asteroid 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. ...

that was discovered by

Elia Millosevich Elia Filippo Francesco Giuseppe Maria Millosevich (5 September 1848 in Venice – 5 December 1919 in Rome) was an Italian astronomer.br>boka - 0.indd/ref> He specialized in calculating the orbits of comets and asteroids, in particular 433 Ero ...

on 1 March 1891 in

Rome , established_title = Founded , established_date = 753 BC , founder = King Romulus (legendary) , image_map = Map of comune of Rome (metropolitan city of Capital Rome, region Lazio, Italy).svg , map_caption ...

. The asteroid was named by the director of the Modena Observatory in honor of the Italian astronomer

Angelo Secchi Angelo Secchi (; 28 June 1818 – 26 February 1878) was an Italian Catholic priest, astronomer from the Italian region of Emilia. He was director of the observatory at the Pontifical Gregorian University (then called the Roman College) for 28 y ...

. It is classified as an

S-type asteroid S-type asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are of this type, making it the second ...

. In the late 1990s, a network of astronomers worldwide gathered

light curve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequ ...

data that was ultimately used to derive the spin states and shape models of 10 new asteroids, including (306) Unitas. The computed shape model for this asteroid is regular, while the light curve displays two maxima per rotation. Lightcurve data has also been recorded by observers at the Antelope Hill Observatory, which has been designated as an official observatory by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function ...

.Lightcurve Results
/ref> Measurements of the

thermal inertia In thermodynamics, a material's thermal effusivity, thermal inertia or thermal responsivity is a measure of its ability to exchange thermal energy with its surroundings. It is defined as the square root of the product of the material's thermal co ...

of 306 Unitas give an estimate range from 100 to 260 m⁻² K⁻¹ s^−1/2, compared to 50 for

lunar regolith Lunar soil is the fine fraction of the regolith found on the surface of the Moon. Its properties can differ significantly from those of terrestrial soil. The physical properties of lunar soil are primarily the result of mechanical disintegra ...

and 400 for coarse sand in an atmosphere. Although 306 Unitas has an orbit similar to the

Vesta family The Vesta family (adj. ''Vestian''; ) is a family of asteroids. The cratering family is located in the inner asteroid belt in the vicinity of its namesake and principal body, 4 Vesta. It is one of the largest asteroid families with more than ...

asteroids, it was found to be an unrelated interloper on the basis of its non-matching

spectral type In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...

. File:306 Unitas Orbit Diagram.png

References

External links

Lightcurve plot of (306) Unitas
Antelope Hills Observatory * * 000306 Discoveries by Elia Millosevich Named minor planets 000306 000306 18910301 {{S-beltasteroid-stub