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.
To focus discussions about how Curiosity will explore the mountain during a two-year prime mission after landing, the mission’s international Project Science Group has decided to call it Mount Sharp. This informal naming pays tribute to geologist Robert P. Sharp (1911-2004), a founder of planetary science, influential teacher of many current leaders in the field, and team member for NASA’s first few Mars missions. Sharp taught geology at the California Institute of Technology (Caltech), in Pasadena, from 1948 until past his retirement. Life magazine named him one of the 10 best college teachers in the nation.
Many of us see a man in the moon—a human face smiling down at us from the lunar surface. The “face,” of course, is just an illusion, shaped by the dark splotches of lunarmaria (smooth plains formed from the lava of ancient volcanic eruptions).
Like a loyal friend, the man is always there, constantly gazing at us as the moon revolves around Earth, locked in what’s called a synchronous orbit, in which the moon rotates exactly once every time it orbits Earth. But why did the moon settle into an orbit with the man—rather than the moon’s crater-covered far side—facing Earth?
Previously, some scientists have thought the fact that we see the man is just the result of a coincidence, a sort of lunar coin toss, says Oded Aharonson, professor of planetary science at the California Institute of Technology (Caltech). But he and his colleagues have now found that is not the case. In the past, the moon spun around its axis faster than it does today, and their new analysis shows that the fact that the man now faces us may be a result of the rate at which the moon slowed down before becoming locked into its current orientation.
Full Story: http://news.caltech.edu/press_releases/13500
Saturn’s largest moon, Titan, is an intriguing, alien world that’s covered in a thick atmosphere with abundant methane. With an average surface temperature of a brisk -300 degrees Fahrenheit (about 90 kelvins) and a diameter just less than half of Earth’s, Titan boasts methane clouds and fog, as well as rainstorms and plentiful lakes of liquid methane. It’s the only place in the solar system, other than Earth, that has large bodies of liquid on its surface.
The origins of many of these features, however, remain puzzling to scientists. Now, researchers at the California Institute of Technology (Caltech) have developed a computer model of Titan’s atmosphere and methane cycle that, for the first time, explains many of these phenomena in a relatively simple and coherent way.
In particular, the new model explains three baffling observations of Titan. One oddity was that Titan’s methane lakes tend to cluster around its poles and that there are more lakes in the northern hemisphere than in the south.
Secondly, the areas at low latitudes, near Titan’s equator, are known to be dry, lacking lakes and regular precipitation. But when the Huygens probe landed on Titan in 2005, it saw channels carved out by flowing liquid-possibly runoff from rain. And in 2009, Caltech researchers discovered raging storms that may have brought rain to this supposedly dry region.
Finally, scientists uncovered a third mystery when they noticed that clouds observed over the past decade—during summer in Titan’s southern hemisphere—cluster around southern middle and high latitudes.
Full Story: http://news.caltech.edu/press_releases/13484