D-type asteroids have a very low

albedo Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that refle ...

and a featureless reddish

spectrum A spectrum (plural ''spectra'' or ''spectrums'') is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors ...

. It has been suggested that they have a composition of organic-rich

silicate In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is a ...

carbon 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 ma ...

and

anhydrous A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achi ...

silicates, possibly with water ice in their interiors. D-type asteroids are found in the outer

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, c ...

and beyond; examples are

152 Atala Atala ( minor planet designation: 152 Atala) is a large main belt asteroid that was discovered by brothers Paul Henry and Prosper Henry on 2 November 1875, but the discovery was credited to Paul. It is a type D asteroid, meaning that it is compo ...

, and

944 Hidalgo 944 Hidalgo is a centaur and unusual object on an eccentric, cometary-like orbit between the asteroid belt and the outer Solar System, approximately in diameter. Discovered by German astronomer Walter Baade in 1920, it is the first member of t ...

as well as the majority of Jupiter trojans. It has been suggested that the Tagish Lake meteorite was a fragment from a D-type asteroid, and that the Martian moon Phobos is closely related. The

Nice model The Nice () model is a scenario for the dynamical evolution of the Solar System. It is named for the location of the Côte d'Azur Observatory—where it was initially developed in 2005—in Nice, France. It proposes the migration of the giant ...

suggests that D-type asteroids may have originated in the

Kuiper belt The Kuiper belt () is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune at 30 astronomical units (AU) to approximately 50 AU from the Sun. It is similar to the asteroid belt, but is far larger—20 tim ...

. 46 D-type asteroids are known, including:

3552 Don Quixote 3552 Don Quixote, provisionally designated , is an exceptionally eccentric asteroid, classified as a near-Earth object of the Amor group, Mars-crosser and Jupiter-crosser, as well as a centaur and extinct comet. Discovery and naming The as ...

, 624 Hektor, and

10199 Chariklo 10199 Chariklo is the largest confirmed centaur (small body of the outer Solar System). It orbits the Sun between Saturn and Uranus, grazing the orbit of Uranus. On 26 March 2014, astronomers announced the discovery of two rings (nickname ...

Examples

A list of some of the largest D-type asteroids.

References

Asteroid spectral classes D-type asteroids {{asteroid-stub

Examples

See also

References