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Giant impacts make a new planetary object: A Synestia

Graduate student Simon Lock and Sarah Stewart describe a new type of planetary object that is created by a giant impact: a synestia. This structure is not like a planet or a traditional planet with an orbiting disk, it something distinct that has different internal structure and dynamics than other planetary objects.

This work is published in the Journal of Geophysical Research: Planets and posted on arXiv.

UC Davis press release
AGU press release
Fleeting phase of planet formation discovered
Scientists propose new kind of planet: A smashed up torus of hot vaporized rock

Where did the word synestia come from?
The name synestia means connected structure. The word is derived from Hestia, the Greek goddess of the hearth, home, architecture and syn means together.

The initial shape of an impact-generated synestia is a biconcave disc. A synestia will change shape as it cools over time.

Image by Simon Lock.

Sarah Stewart’s research group investigates the formation and evolution of planetary bodies. Our primary techniques are shock wave experiments to measure material properties and numerical simulations of planetary processes. We tackle a broad range of problems in planetary science by focusing on understanding the feedbacks between physical processes and changes in material properties.

New Tidal Evolution Model for the Moon

We have a new model for the tidal evolution of the Moon, published in Nature. The model begins with a giant impact that tilts the Earth about 70 degrees from the ecliptic. Learn more about the Origin of the Moon. (Image from eskipaper.com)

UC Davis: New Theory Explains How the Moon Got There
SETI: Did Early Earth Spin on Its Side?
U. Maryland: New model explains the moon’s weird orbit

Stewart Group News

Planet Cakes!

May 22nd, 2017|Comments Off on Planet Cakes!

The Origins Group finds many reasons to throw a party. The latest reason was making planet cakes! We made Jupiter and Earth with Pangea. (Image gallery -- click on the cakes)

Synestia, a New Type of Planetary Object

May 22nd, 2017|Comments Off on Synestia, a New Type of Planetary Object

Graduate student Simon Lock and Sarah Stewart define and explain a new type of planetary object. A synestia is formed by a giant impact. Synestias are an important stage of terrestrial planet formation, leading to mixing [...]

New Center for Frontiers in High Energy Density Science

November 16th, 2016|Comments Off on New Center for Frontiers in High Energy Density Science

U. California has funded a new center in high energy density science. This center is a collaboration between 5 UC campuses, LLNL and LANL. One of the themes of our center is material properties under [...]

Graduate program application deadline is December 15

November 8th, 2016|Comments Off on Graduate program application deadline is December 15

Please contact Sarah if you are interested in our graduate program in planetary sciences. Our application deadline have moved to December 15.

Tidal Evolution of the Moon: Earth started tilted over

October 31st, 2016|Comments Off on Tidal Evolution of the Moon: Earth started tilted over

Our new model for the tidal evolution of the moon was published online today in Nature: Tidal Evolution of the Moon from a high-obliquity, high-angular-momentum Earth. The tidal evolution is a big piece of the [...]

The 2-stage gas gun is here!

October 30th, 2016|Comments Off on The 2-stage gas gun is here!

We are installing the new 2-stage light gas gun. This instrument lets us reach pressures found in the Earth's core. It was built by Physics Applications Inc.

More Stewart Group News……

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Building the New Lab

UC Davis Shock Compression Laboratory under construction.

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