[meteorite-list] Jupiter Not The Planetary Shield We Thought It Was

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 15 Feb 2016 22:15:06 -0800 (PST)
Message-ID: <201602160615.u1G6F67v029573_at_zagami.jpl.nasa.gov>

http://newuniversedaily.com/2016/02/06/jupiter-not-the-planetary-shield-we-thought-it-was

Jupiter Not The Planetary Shield We Thought It Was
New Universe Daily
February 6, 2016

The "Jupiter as a shield" theory implies that the planets massive
gravity protects Earth from comet impacts by attracting most of the action
before it reaches Earth, but new research says that hypothesis is incorrect.

Models formulated by Dr. Kevin Grazier at NASA's Jet Propulsion Laboratory
suggest that not only did Jupiter not protect us, but that it, along with
Saturn likely played a vital roll in shuttling material into Earths orbit.
The findings were published in the journal Astrobiology.

Grazier, along with his team, created models simulating the evolution
of particles in the orbital gap between the two gas giant planets. The
simulations shows that Jupiter and Saturn team up to deflect a significant
portion of those particles into the inner solar system.

Despite Jupiter losing the protector label, scientists still think that
a solar system with one or more planets similar to Jupiter, located beyond
the region of the habitable zone, is beneficial for the development of
life. It's likely that Saturn and Jupiter played a critical role in
shuttling exotic material from the outer solar system that helped support
life here on Earth.

"In an unprecedented effort to solve the riddle as to whether jovian
bodies shield habitable planets from impacts catastrophic to life, Dr.
Grazier presents a modeling study that speaks to the incredible complexity
of planetisimal evolution in the Solar System," said Dr. Sherry Cady,
Editor-in-Chief of Astrobiology.

"In this paper, we learn that the overly simplistic 'Jupiter as shield'
concept is a thing of the past, and future research in this area will
require the continued use of the kinds of robust simulation strategies
so effectively employed in Dr. Grazier's work."
Received on Tue 16 Feb 2016 01:15:06 AM PST