Category Astronomy/Space

Artist impression of the Milky Way Galaxy. Using the Green Bank Telescope, astronomers measured the relative abundance of light to heavy isotopes of silicon, as found in the molecule silicon monoxide, across the Milky Way. Surprisingly, the astronomer found none of the expected gradient — higher ratio of heavier silicon isotopes — toward the galactic center. This may suggest that the Milky Way is more efficient at mixing its contents than previously assumed. Credit: Alexandra Angelich (NRAO/AUI/NSF)

As galaxies age, some of their basic chemical elements can also show signs of aging. This aging process can be seen as certain atoms “put on a little weight,” meaning they change into heavier isotopes – atoms with additional neutrons in their nuclei...

This unprocessed image of Saturn’s moon Titan was captured by NASA’s Cassini spacecraft during its final close flyby of the hazy, planet-sized moon on April 21, 2017. Credit: NASA/JPL-Caltech/Space Science Institute

NASA’s Cassini spacecraft has had its last close brush with Saturn’s hazy moon Titan and is now beginning its final set of 22 orbits around the ringed planet. The spacecraft made its 127th and final close approach to Titan on April 21 at 11:08 p.m. PDT (2:08 a.m. EDT on April 22), passing at an altitude of about 608 miles above the moon’s surface. Cassini transmitted its images and other data to Earth following the encounter...

The map of the cosmic microwave background (CMB) sky produced by the Planck satellite. Red represents slightly warmer regions, and blue slightly cooler regions. The Cold Spot is shown in the inset, with coordinates on the x- and y-axes, and the temperature difference in millionths of a degree in the scale at the bottom. Credit: ESA and Durham University. Click for a full size image

A supervoid is unlikely to explain a ‘Cold Spot’ in the cosmic microwave background, according to the results of a new survey, leaving room for exotic explanations like a collision between universes. The cosmic microwave background (CMB), a relic of the Big Bang, covers the whole sky. At 2.73 degrees above 0K, the CMB has some anomalies, including the Cold Spot. This feature, about 0...

Mars bears the scars of five giant impacts, including the ancient giant Borealis basin (top of globe), Hellas (bottom right), and Argyre (bottom left). An SwRI-led team discovered that Mars experienced a 400-million-year lull in impacts between the formation of Borealis and the younger basins. Credit: University of Arizona/LPL/Southwest Research Institute

Studying the early bombardment history of Mars, scientists have discovered a 400-million-year lull in large impacts early in Martian history. “The new results reveal that Mars’ impact history closely parallels the bombardment histories we’ve inferred for the Moon, the asteroid belt, and the planet Mercury,” Bottke said. “We refer to the period for the later impacts as the ‘Late Heavy Bombardment...