Category Astronomy/Space

Gale Crater on surface of Mars was once filled with liquid water for 10,000 to 10 million years, according to findings from the Mars Science Laboratory (MLS). A new study from Penn State scientists suggests dramatic climate cycles may have produced warm periods long enough to thaw the planet and create the water features on the surface today. From Topographic evidence for lakes in Gale Crater, abstract, 44th Lunar and Planetary Science Conference (2013). Credit: William Dietrich / University of California Berkley

Dramatic climate cycles on early Mars, triggered by buildup of greenhouse gases, may be the key to understanding how liquid water left its mark on the planet’s surface, according to a team of planetary scientists...

Grant Mathews believes the event that led the Magi — Zoroastrian priests of ancient Babylon and Mesopotamia — was an extremely rare planetary alignment occurring in 6 B.C., and the likes of which may never be seen again. Credit: University of Notre Dame

The Star of Bethlehem, and its origin, has been one of those mysteries pondered by scientists for centuries – and something Grant Mathews, professor of theoretical astrophysics and cosmology in the Dept of Physics, University of Notre Dame, has studied for more than a decade. “Astronomers, historians and theologians have pondered the question of the ‘Christmas Star’ for many years,” said Mathews...

Small near-Earth asteroids are important targets of study because not much is known about them. By characterizing the smallest of the bunch, scientists can better understand the population of objects from which they originate: large asteroids, which have a much smaller likelihood of impacting Earth. (Image: NASA/JPL-Caltech)

Astronomers have obtained observations of the smallest asteroid ever characterized in detail. At 6 feet in diameter, the tiny space rock is small enough to be straddled by a person in a hypothetical space-themed sequel to the iconic bomb-riding scene in the movie “Dr. Strangelove.” Interestingly, the asteroid, named 2015 TC25, is also one of the brightest near-Earth asteroids ever discovered...

Pluto, shown here in the front of this false-color image, has a bright ice-covered ‘heart.’ The left, roughly oval lobe is the basin provisionally named Sputnik Planitia. Sputnik Planitia appears directly opposite Pluto’s moon, Charon (back). Credit: NASA/JHUAPL/SWRI

Heart’s location and Charon’s existence led to heart’s formation. Pluto’s “icy heart” is a bright, two-lobed feature on its surface that has attracted researchers ever since its discovery by the NASA New Horizons team in 2015. Of particular interest is the heart’s western lobe, informally named Sputnik Planitia, a deep basin containing 3 kinds of ices – frozen nitrogen, methane and CO — and appearing opposite Charon, Pluto’s tidally locked moon...