Atlantis Arisen
May 27, 2020, 01:25:25 am
Welcome, Guest. Please login or register.

Login with username, password and session length
News: First Orchid Fossil Found in Amber
http://news.nationalgeographic.com/news/2007/08/070829-orchid-fossil.html
 
  Home Help Search Arcade Links Staff List Login Register  

Giant impact hypothesis

Pages: [1]   Go Down
  Print  
Author Topic: Giant impact hypothesis  (Read 854 times)
Deanna Witmer
Atlantean Hero
*****
Posts: 126



View Profile
« on: October 18, 2010, 01:18:10 pm »

Theia

The name of the hypothesized protoplanet is derived from the mythical Greek goddess Theia, a Titan who gave birth to the Moon goddess Selene. According to the giant impact hypothesis, Theia formed alongside the other planet size bodies in the Solar System about 4.6 Ga (4.6 billion years ago), and was approximately the size of Mars.

One formation theory is that Theia materialized at the L4 or L5 Lagrangian points relative to Earth (in about the same orbit and about 60° ahead or behind),[1] similar to a trojan asteroid.[9] The stability of Theia's orbit was affected when its growing mass exceeded a threshold of about 10% of the Earth's mass.[1] Gravitational perturbations by planetesimals caused Theia to depart from its stable Lagrangian location, and subsequent interactions with proto-Earth caused the two bodies to collide.[1]

Astronomers think the collision between Earth and Theia happened about 4.53 Ga; about 30-50 million years after the rest of the Solar System formed. However, evidence presented in 2008 suggests that the collision may have occurred later, at about 4.48 Ga.[10]

Report Spam   Logged


Pages: [1]   Go Up
  Print  
 
Jump to:  

Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum

Powered by SMF | SMF © 2016, Simple Machines
Privacy Policy