pebbles tagged posts

Why Earth is so much bigger than Mars: Rocky Planets formed from ‘Pebbles’

Southwest Research Institute scientists developed a new process in planetary formation modeling that explains the size and mass difference between the Earth and Mars. Mars is much smaller and has only 10 percent of the mass of the Earth. Conventional solar system formation models generate good analogs to Earth and Venus, but predict that Mars should be of similar-size, or even larger than Earth. Credit: Image Courtesy of NASA/JPL/MSSS

Southwest Research Institute scientists developed a new process in planetary formation modeling that explains the size and mass difference between the Earth and Mars. Mars is much smaller and has only 10 percent of the mass of the Earth. Conventional solar system formation models generate good analogs to Earth and Venus, but predict that Mars should be of similar-size, or even larger than Earth. Credit: Image Courtesy of NASA/JPL/MSSS

Using a new process in planetary formation modeling, where planets grow from tiny bodies called ‘pebbles,’ scientists can explain why Mars is so much smaller than Earth. This same process also explains the rapid formation of the gas giants Jupiter and Saturn, as reported earlier this year.

“This numerical simulation actually reproduces the structure of the in...

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Astronomers see Ring of Rocks Circling Very Young Star




These ‘pebbles’ detected for 1st time: crucial link in building planets. Since1990s, astronomers have found both disks of gas and dust, and nearly 2000 fully formed planets, but the intermediate stages of formation are harder to detect.

Dr Greaves and Dr Anita Richards from Manchester University used e-MERLIN array of radio telescopes centred on Jodrell Bank, Cheshire, and that stretches across England in an interferometer, mimicking resolution of a single large telescope. They observed the star DG Tauri, a youthful star just 2.5 million years old and 450 light years away in constellation of Taurus. Looking at radio wavelengths, they discovered a faint glow characteristic of rocks in orbit around the newly formed star.

An artist's impression of the belt of ‘pebbles’ in orbit around the star DG Tauri. The inset is a close up view of a section of the belt.

An artist’s imp...

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