Having a companion in old age is good for people — and, it turns out, might extend the chance for life on certain Earth-sized planets in the cosmos as well.
Planets cool as they age. Over time their molten cores solidify and inner heat-generating activity dwindles, becoming less able to keep the world habitable by regulating carbon dioxide to prevent runaway heating or cooling. (more…)
Using NASA’s Kepler Space Telescope, astronomers have discovered the first Earth-size planet orbiting a star in the “habitable zone” — the range of distance from a star where liquid water might pool on the surface of an orbiting planet. The discovery of Kepler-186f confirms that planets the size of Earth exist in the habitable zone of stars other than our sun.
While planets have previously been found in the habitable zone, they are all at least 40 percent larger in size than Earth, and understanding their makeup is challenging. Kepler-186f is more reminiscent of Earth. (more…)
Massive terrestrial planets, called “super-Earths,” are known to be common in Earth’s galaxy, the Milky Way. Now a Northwestern University astrophysicist and a University of Chicago geophysicist report the odds of these planets having an Earth-like climate are much greater than previously thought.
Nicolas B. Cowan and Dorian Abbot’s new model challenges the conventional wisdom, which says super-Earths actually would be very unlike Earth—each would be a waterworld, with its surface completely covered in water. They conclude that most tectonically active super-Earths—regardless of mass—store most of their water in the mantle and will have both oceans and exposed continents, enabling a stable climate such as Earth’s. (more…)
This holiday season, feast your eyes on images of Saturn and two of its most fascinating moons, Titan and Enceladus, in a care package from NASA’s Cassini spacecraft. All three bodies are dressed and dazzling in this special package assembled by Cassini’s imaging team.
The new images are available online at: https://www.nasa.gov/cassini , https://saturn.jpl.nasa.gov and https://ciclops.org .
“During this, our tenth holiday season at Saturn, we hope that these images from Cassini remind everyone the world over of the significance of our discoveries in exploring such a remote and beautiful planetary system,” said Carolyn Porco, Cassini imaging team leader, based at the Space Science Institute, Boulder, Colo. “Happy holidays from all of us on Cassini.” (more…)
There is only one planet we know of, so far, that is drenched with life. That planet is Earth, as you may have guessed, and it has all the right conditions for critters to thrive on its surface. Do other planets beyond our solar system, called exoplanets, also host life forms?
Astronomers still don’t know the answer, but they search for potentially habitable planets using a handful of criteria. Ideally, they want to find planets just like Earth, since we know without a doubt that life took root here. The hunt is on for planets about the size of Earth that orbit at just the right distance from their star – in a region termed the habitable zone. (more…)
PASADENA, Calif. — NASA’s Kepler mission scientists have discovered a new planetary system that is home to the smallest planet yet found around a star similar to our sun.
The planets are located in a system called Kepler-37, about 210 light-years from Earth in the constellation Lyra. The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. It is smaller than Mercury, which made its detection a challenge. (more…)
In their search for habitable worlds, astronomers have started to consider exomoons, or those likely orbiting planets outside the solar system. In a new study, a pair of researchers has found that exomoons are just as likely to support life as exoplanets.
The research, conducted by Rory Barnes of the University of Washington and the NASA Astrobiology Institute and René Heller of Germany’s Leibniz Institute for Astrophysics Potsdam, will appear in the January issue of Astrobiology. Heller is lead author of the paper. (more…)
PASADENA, Calif. – NASA’s Kepler mission Monday announced the discovery of 461 new planet candidates. Four of the potential new planets are less than twice the size of Earth and orbit in their sun’s “habitable zone,” the region in the planetary system where liquid water might exist on the surface of a planet.
Based on observations conducted from May 2009 to March 2011, the findings show a steady increase in the number of smaller-size planet candidates and the number of stars with more than one candidate. (more…)
