Search results
Results from the WOW.Com Content Network
Chondrules in the chondrite classification Grassland. A millimeter scale is shown. Chondrules in the Carbonaceous Chondrite NWA 13887. A chondrule (from Ancient Greek χόνδρος chondros, grain) is a round grain found in a chondrite. Chondrules form as molten or partially molten droplets in space before being accreted to their parent asteroids.
A chondrite / ˈ k ɒ n d r aɪ t / is a stony (non-metallic) meteorite that has not been modified by either melting or differentiation of the parent body. [a] [1] They are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids.
Chondrules, metal grains, and other components likely formed in the solar nebula. These accreted together to form parent asteroids. These accreted together to form parent asteroids. Some of these bodies subsequently melted, forming metallic cores and olivine -rich mantles ; others were aqueously altered. [ 35 ]
Aqueous alteration promotes a composition of hydrous phyllosilicates, magnetite, and olivine crystals occurring in a black matrix, and a possible lack of chondrules. It is thought they have not been heated above 50 °C (122 °F), indicating that they condensed in the cooler outer portion of the solar nebula.
The Sun; Sirius A with Sirius B, a white dwarf; the Crab Nebula, a remnant supernova; A black hole (artist concept); Vela Pulsar, a rotating neutron star; M80, a globular cluster, and the Pleiades, an open star cluster; The Whirlpool Galaxy and Abell 2744, a galaxy cluster; Superclusters, galactic filaments and voids
no chondrules: very clearly defined chondrules: well defined chondrules: chondrules can be recognized: poorly recog- nizable chondrules: relict chondrules Matrix: fine grained opaque: chiefly fine, opaque: clastic and minor opaque: coarse grained transparent, recrystallized, coarsening from type 4 to 7 Homogeneity of ol + px (Fe, Mg content) –
NGC 604, a giant H II region in the Triangulum Galaxy, taken by the Hubble Space Telescope. An H II region is a region of interstellar atomic hydrogen that is ionized. [1] It is typically in a molecular cloud of partially ionized gas in which star formation has recently taken place, with a size ranging from one to hundreds of light years, and density from a few to about a million particles per ...
A protoplanetary nebula or preplanetary nebula [27] (PPN, plural PPNe) is an astronomical object which is at the short-lived episode during a star's rapid evolution between the late asymptotic giant branch (LAGB) phase and the subsequent planetary nebula (PN) phase.