Chondrule Formation by Impact?
The CB chondrites (at least Gujba and HH 237) formed after the solar nebula had finished being energetic. Yet their formation indicates an energetic process was involved.
For example, the metal was melted and some seems to have formed from a vapor. Chondrules were totally molten droplets that contained no pre-existing debris and cooled rapidly. All these features point a cosmic finger at formation during an impact event.
In a collision between large objects, there is a lot of vaporization and melting. These hot conditions provide settings in which metal nodules and skeletal olivine chondrules form by melting, and cryptocrystlline chondrules (which are smaller) are made by condensation from a vapor.
There are no unmelted remnants of the original materials left in these meteorites. This is consistent with their formation by impact between two objects the size of Earth's Moon. Such a monumental collision would separate melt and vapor from unmelted materials.
Collision between two Moon-sized (or larger) objects in the early Solar System would have produced vast amounts of melt and vapor, from which the components in CB chondrites could have formed. Such impacts may have been common for a few million years early in the evolution of the Solar System.
|
Pages
The Mary Elizabeth Collection
Solar System
Before the Beginning
Our Beginning
Comets
Stardust - A Robotic Mission
The Stones
Abee - The Mystery
Allende - A Blast
Axtell
Bonita Springs
Cat Mountain
Chergach (aka Mali)
Claxton
Gujba
Kendleton
Melrose - The Golden One
Millbillillie
Mundrabilla
Murchison
Saratov
Vesta & Its Meteorites
Bilanga
Chaves
Sioux County
Stony Irons
Beautiful Esquel
Brenham
Pallas Iron
Vaca Muerta
The Irons
An American Icon
Campo Del Cielo
Cape of Good Hope
Coahuila
Gibeon
Henbury
The Mythic Kaalijarv
Nantan
Nelson County
Sikhote-Alin
Wolfe Creek
Historic Meteorites
Orgueil - & the Comet
Pultusk Shower
Weston
Glossary
Impact Features
Rocks
Craters of the World
Events
Mass Extinctions
Moon Rocks FAQs
Links
Types
of Meteorites
Pallasites
-- A Rare View
Meteor Showers
Interesting
meteorite falls
NASA's Earth & Space Sciences
Near-Earth Object (NEO) Program
Basic Science II: Impact Cratering
Chesapeake Bay impact crater
Media
Peekskill
N.Y. fireball video
London Natural History
Museum video
Video
of crater in Arizona
Understanding: Prehistoric Meteor Hit the Caribbean Sea
If interested in meteorites, we are happy to link you
to these outstanding sites:
|
