Possibility of “Super Earths”
The 211th meeting of the American Astronomical Society press conference talked about research concerning “plate tectonics”. Astronomers at the Harvard-Smithsonian Center have shown that the earth would be smaller in size and be less massive if these were no plate tectonics. Also, life may never have existed on earth. “Plate tectonics are essential to life as we know it”, said Diane Valencia of Harvard University. “Our calculations show that bigger is better when it comes to the habitability of rocky p[planets”.
The movement of huge chunks, or plates of a planet’s surface are because of plate tectonics. Gigantic mountain ranges, such as the Himalayas are lifted when the plates slide under one another, spread apart from each other, or may crash into each other. Magna, boiling under the surface powers the plate tectonics. As the magna cools, it forms the crust of the planet. The planet’s habitability is dependent on the plate’s tectonics as they enable complex chemistry and recycle substances like carbon dioxide, which keep the earth balmy and acts as a thermostat. As the rocks melt, the carbon dioxide is released from the rocks where it has been locked in, and returns to the atmosphere from volcanoes and oceanic ridges. “Recycling is important even on a planetary scale”, Valencia explained.
The extremes were examined to decide if plate tectonics would be more or less likely on different-sized rocky worlds. So called “Super-Earths”—planets more than twice the size of earth and up to ten times as massive, were studied. The teams working on this study is as composed of Valencia and her colleagues, Richard O’Connell and Dimitar Sasselov (Harvard University).
According to their research, the team found that a super-earth would be more geologically active than earth and would the plate tectonics be under more stress. While Venus, a smaller planet, is tectonically inactive, the earth is a borderline case. “It might not be a coincidence that earth is the largest rocky planet in our solar system, and also the only one with life”, said Valencia. Five super-earths have been discovered by exoplanet searches but none have like-friendly temperatures.
Some of the super-earths possibly enjoy earth-like orbits making them planets where humans could possibly live. “There are not only more potentially habitable planets, but ‘many’ more”, stated Sasselov, who is director of the Harvard Origins of Life Initiative. An earth-like atmosphere would be possible and the surface gravity would be three times that of earth. He added that a super-earth would be doubled the size of our home planet and would have similar geography with weather the same as earth.
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