E-class asteroid

A rare category of asteroid, slightly red in color and spectrally similar to M-class asteroids and P-class asteroids, but of higher albedo (in the range 0.25-0.60). E-class asteroids dominate the Hungaria group of the main belt, though some, including the two largest, (44) Nysa (see Nysa-Polana family and (64) Angelina, are found scattered further out. Their flat reflectance spectra in the 0.3 to 1.0 micron region and high albedos suggest a connection with the aubrite (otherwise known as enstatite achondrite, hence the "E") category of meteorite. However, this link is problematic because aubrites are clearly of igneous origin, whereas some E-class asteroids (including Nysa) show an absorption feature at 3 microns that points to water- and/or hydroxyl-bearing minerals and a non-igneous history.

Related category

• ASTEROIDS AND OTHER MINOR PLANETS: TYPES AND GROUPS

Also on this site:

Encyclopedia of Alternative Energy & Sustainable Living
Encyclopedia of History

BACK TO TOP