Featured Research

from universities, journals, and other organizations

Lunar 'hit-and-run': New research eclipses existing theories on formation of the moon

Date:
August 29, 2012
Source:
Elsevier
Summary:
A new study highlights a novel perspective on how the moon was formed. The moon is believed to have formed from a collision, 4.5 billion years ago, between Earth and an impactor the size of Mars, known as "Theia." Over the past decades scientists have simulated this process and reproduced many of the properties of the Earth-moon system; however, these simulations have also given rise to a problem known as the Lunar Paradox: the moon appears to be made up of material that would not be expected if the current collision theory is correct. A recent study proposes a new perspective on the theory in answer to the paradox.

Lunar Eclipse on December 10, 2011.
Credit: natuska106 / Fotolia

The Moon is believed to have formed from a collision, 4.5 billion years ago, between Earth and an impactor the size of Mars, known as "Theia." Over the past decades scientists have simulated this process and reproduced many of the properties of the Earth-Moon system; however, these simulations have also given rise to a problem known as the Lunar Paradox: the Moon appears to be made up of material that would not be expected if the current collision theory is correct.

Related Articles


A recent study published in Icarus proposes a new perspective on the theory in answer to the paradox.

If current theories are to be believed, analyses of the various simulations of the Earth-Theia collision predict that the Moon is mostly made up of material from Theia. However, studying materials from both Earth and the Moon, shows remarkable similarities. In fact, elements found on the Moon show identical isotopic properties to those found on Earth.

Given it is very unlikely that both Theia and Earth had identical isotopic compositions (as all other known solar system bodies, except the Moon, appear to be different) this paradox casts doubt over the dominant theory for the Moon formation. Moreover, for some elements, like Silicon, the isotopic composition is the result of internal processes, related to the size of the parent body. Given Theia was smaller than Earth, its Silicon isotope composition should have definitely been different from that of Earth's mantle.

A group of researchers from the University of Bern, Switzerland, have now made a significant breakthrough in the story of the formation of the Moon, suggesting an answer to this Lunar Paradox. They explored a different geometry of collisions than previously simulated, also considering new impacts configurations such as the so-called, "hit-and-run collisions," where a significant amount of material is lost into space on orbits unbound to Earth..

"Our model considers new impact parameters, which were never tested before. Besides the implications for the Earth-Moon system itself, the considerably higher impact velocity opens up new possibilities for the origin of the impactor and therefore also for models of terrestrial planet formation," explains lead author of the study, Andreas Reufer.

"While none of the simulations presented in their research provides a perfect match for the constraints from the actual Earth-Moon-system, several do come close," adds Alessandro Morbidelli, one of the Icarus' Editors. "This work, therefore, suggests that a future exhaustive exploration of the vast collisional parameter space may finally lead to the long-searched solution of the lunar paradox."


Story Source:

The above story is based on materials provided by Elsevier. Note: Materials may be edited for content and length.


Journal Reference:

  1. Andreas Reufer, Matthias M.M. Meier, Willy Benz, Rainer Wieler. A hit-and-run Giant Impact scenario. Icarus, 2012 (in press) DOI: 10.1016/j.icarus.2012.07

Cite This Page:

Elsevier. "Lunar 'hit-and-run': New research eclipses existing theories on formation of the moon." ScienceDaily. ScienceDaily, 29 August 2012. <www.sciencedaily.com/releases/2012/08/120829064827.htm>.
Elsevier. (2012, August 29). Lunar 'hit-and-run': New research eclipses existing theories on formation of the moon. ScienceDaily. Retrieved March 30, 2015 from www.sciencedaily.com/releases/2012/08/120829064827.htm
Elsevier. "Lunar 'hit-and-run': New research eclipses existing theories on formation of the moon." ScienceDaily. www.sciencedaily.com/releases/2012/08/120829064827.htm (accessed March 30, 2015).

Share This


More From ScienceDaily



More Space & Time News

Monday, March 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

What NASA Wants To Learn From Its 'Year In Space' Tests

What NASA Wants To Learn From Its 'Year In Space' Tests

Newsy (Mar. 28, 2015) Astronaut Scott Kelly and cosmonaut Mikhail Kornienko will spend a year in space running tests on human physiology and psychology. Video provided by Newsy
Powered by NewsLook.com
Raw: Astronauts Arrive at ISS for 1-Year Mission

Raw: Astronauts Arrive at ISS for 1-Year Mission

AP (Mar. 28, 2015) The capsule carrying a Russian and an American who are to spend a year away from Earth docked Saturday with the International Space Station. (March 28) Video provided by AP
Powered by NewsLook.com
Crew Starts One-Year Space Mission

Crew Starts One-Year Space Mission

Reuters - News Video Online (Mar. 28, 2015) Russian-U.S. crew arrives safely at the International Space Station for the start of a ground-breaking year-long stay. Paul Chapman reports. Video provided by Reuters
Powered by NewsLook.com
Why So Many People Think NASA's Asteroid Mission Is A Waste

Why So Many People Think NASA's Asteroid Mission Is A Waste

Newsy (Mar. 27, 2015) The Asteroid Retrieval Mission announced this week bears little resemblance to its grand beginnings. Even NASA scientists are asking, "Why bother?" Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins