L-type asteroid
Encyclopedia
L-type asteroids are relatively uncommon asteroid
s with a strongly reddish spectrum shortwards of 0.75 μm, and a featureless flat spectrum longwards of this. In comparison with the K-type
, they exhibit a more reddish spectrum at visible wavelengths and a flat spectrum in the infrared.
These asteroids were described as "featureless" S-types
in the Tholen classification. The L-type was formally introduced in the SMASS classification, although previous studies had noted the unusual spectra of two of its members 387 Aquitania
and 980 Anacostia
.
. An example may be 728 Leonisis
, although it has also been classified as an A-type
.
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
s with a strongly reddish spectrum shortwards of 0.75 μm, and a featureless flat spectrum longwards of this. In comparison with the K-type
K-type asteroid
K-type asteroids are relatively uncommon asteroids with a moderately reddish spectrum shortwards of 0.75 μm, and a slight bluish trend longwards of this. They have a low albedo. Their spectrum resembles that of CV and CO meteorites....
, they exhibit a more reddish spectrum at visible wavelengths and a flat spectrum in the infrared.
These asteroids were described as "featureless" S-types
S-type asteroid
S-type asteroids are of a stony composition, hence the name. Approximately 17% of asteroids are of this type, making it the second most common after the C-type.-Characteristics:...
in the Tholen classification. The L-type was formally introduced in the SMASS classification, although previous studies had noted the unusual spectra of two of its members 387 Aquitania
387 Aquitania
387 Aquitania is a fairly large main-belt asteroid. It is classified as an S-type asteroid.It was discovered by F. Courty on March 5, 1894, in Bordeaux. It was second of his two asteroid discoveries. The first was 384 Burdigala.-External links:...
and 980 Anacostia
980 Anacostia
980 Anacostia is a minor planet orbiting the Sun.-External links:*...
.
Ld-type asteroids
A grouping proposed in the SMASS classification for asteroids with an L-like flat spectrum longwards of 0.75 μm, but even redder in visible wavelengths, like the D-typeD-type asteroid
D-type asteroids have a very low albedo and a featureless reddish electromagnetic spectrum. It has been suggested that they have a composition of organic rich silicates, carbon and anhydrous silicates, possibly with water ice in their interiors...
. An example may be 728 Leonisis
728 Leonisis
728 Leonisis is an asteroid of the Flora family, discovered by J. Palisa in 1912 in Vienna.There is some uncertainty as to its spectral class. It has been previously placed in the rare A and Ld classes . These are generally "stony" spectra, but with significant deviations from the usual S-type...
, although it has also been classified as an A-type
A-type asteroid
A-type asteroids are relatively uncommon inner-belt asteroids that have a strong, broad 1 µm olivine feature and a very reddish spectrum shortwards of 0.7 µm. They are thought to come from the completely differentiated mantle of an asteroid....
.