The number of known places in our galaxy theoretically hospitable to life may be significantly greater than previously thought, according to new research.
Researchers with Planet Hunters are reporting the discovery of a Jupiter-sized planet in the so-called “habitable zone” of a star similar to Earth’s sun, as well as the identification of 15 new candidate planets also orbiting within their star’s habitable zone. (more…)
UA astronomy students Kevin Hardegree-Ullman and Jake Turner designed, proposed, conducted and presented research on two recently discovered planets outside of our solar system while they were still undergraduates.
Deep in the cosmos, alien planets are circling distant stars, waiting to be pierced by the far-reaching gaze of Earth-bound telescopes. Some are Earth-like and have the potential to harbor liquid water and maybe even life. Others are enormous, gassy giants. All of them are different than any planet we know.
They are the exoplanets, planets outside of our solar system, which astronomers are only just beginning to discover and analyze.
Kevin Hardegree-Ullman and Jake Turner, then University of Arizona undergraduate astronomy students, decided to get to know two of them a little better. (more…)
In ancient Earth history, the sun burned as much as 30 percent dimmer than it does now. Theoretically that should have encased the planet in ice, but there is geologic evidence for rivers and ocean sediments between 2 billion and 4 billion years ago.
Scientists have speculated that temperatures warm enough to maintain liquid water were the result of a much thicker atmosphere, high concentrations of greenhouse gases or a combination of the two. (more…)
One particular mountain on Mars, bigger than Colorado’s grandest, has been beckoning would-be explorers since it was first sighted from orbit in the 1970s. Scientists have ideas about how it took shape in the middle of ancient Gale Crater and hopes for what evidence it could yield about whether conditions on Mars have favored life.
No mission to Mars dared approach it, though, until NASA’s Mars Science Laboratory mission, which this August will attempt to place its one-ton rover, Curiosity, at the foot of the mountain. The moat of flatter ground between the mountain and the crater rim encircling it makes too small a touchdown target to have been considered safe without precision-landing innovations used by this mission. (more…)
The High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter recorded a scene on Jan. 29, 2012, that includes the first color image from orbit showing the three-petal lander of NASA’s Mars Exploration Rover Spirit mission. Spirit drove off that lander platform in January 2004 and spent most of its six-year working life in a range of hills about two miles to the east.
Another recent image from HiRISE, taken on Jan. 26, 2012, shows NASA’s Phoenix Mars Lander and its surroundings on far-northern Mars after that spacecraft’s second Martian arctic winter. Phoenix exceeded its planned mission life in 2008, ending its work as solar energy waned during approach of its first Mars winter. (more…)
PASADENA, Calif. — NASA’s Kepler mission has discovered the first Earth-size planets orbiting a sun-like star outside our solar system. The planets, called Kepler-20e and Kepler-20f, are too close to their star to be in the so-called habitable zone where liquid water could exist on a planet’s surface, but they are the smallest exoplanets ever confirmed around a star like our sun.
The discovery marks the next important milestone in the ultimate search for planets like Earth. The new planets are thought to be rocky. Kepler-20e is slightly smaller than Venus, measuring 0.87 times the radius of Earth. Kepler-20f is slightly larger than Earth, measuring 1.03 times its radius. Both planets reside in a five-planet system called Kepler-20, approximately 1,000 light-years away in the constellation Lyra. (more…)
PASADENA, Calif. — NASA’s Kepler mission has confirmed its first planet in the “habitable zone,” the region around a star where liquid water could exist on a planet’s surface. Kepler also has discovered more than 1,000 new planet candidates, nearly doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host star. Candidates require follow-up observations to verify they are actual planets.
The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our sun. The planet is about 2.4 times the radius of Earth. Scientists don’t yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets. (more…)
PASADENA, Calif. — NASA’s Mars Reconnaissance Orbiter has discovered the total amount of atmosphere on Mars changes dramatically as the tilt of the planet’s axis varies. This process can affect the stability of liquid water, if it exists on the Martian surface, and increase the frequency and severity of Martian dust storms.
Researchers using the orbiter’s ground-penetrating radar identified a large, buried deposit of frozen carbon dioxide, or dry ice, at the Red Planet’s south pole. The scientists suspect that much of this carbon dioxide enters the planet’s atmosphere and swells the atmosphere’s mass when Mars’ tilt increases. The findings are published in this week’s issue of the journal Science. (more…)
