Red Freckles on Europa Suggest ‘Lava Lamp’ Action
Reddish spots on the icy surface of Jupiter’s moon Europa may indicate pockets of warmer ice rising from below. This upwelling could provide an elevator ride to the surface for material in an ocean beneath the ice, say scientists studying data from NASA’s Galileo spacecraft.
Researchers working at CERN, the European Organization for Nuclear Research, say they have for the first time probed the properties of whole atoms of antimatter, the “mirror image” of matter. Their results provide the first look into the inside of an antimatter atom and are a big step on the way to testing standard theories of how the universe operates.
New evidence from NASA’s Chandra X-ray Observatory challenges an alternative theory of gravity that eliminates the need for dark matter. The observation also narrows the field for competing forms of dark matter, the elusive material thought to be the dominant form of matter in the universe. An observation of the galaxy NGC 720 shows it is enveloped in a slightly flattened, or ellipsoidal cloud of hot gas that has an orientation different from that of the optical image of the galaxy. The flattening is too large to be explained by theories in which stars and gas are assumed to contain most of the mass in the galaxy. “The shape and orientation of the hot gas cloud require it to be confined by an egg-shaped dark matter halo,” said a researcher involved in the stoudy. “This means that dark matter is not just an illusion due to a shortcoming of the standard theory of gravity ? it is real.”
Contrary to an opinion held by some researchers, a new analysis of more than 20 years of historical data has found no evidence that the increasing number of large icebergs off Antarctica’s coasts is a result of global warming trends. “The dramatic increase in the number of large icebergs as recorded by the National Ice Center database does not represent a climatic change,” said Brigham Young University’s David Long. “Our reanalysis suggests that the number of icebergs remained roughly constant from 1978 to the late 1990s.” Using BYU’s supercomputers, Long enhanced images of the waters around Antarctica transmitted by satellite. Comparing this data to records from the federal government’s National Ice Center, which tracks icebergs larger than ten miles on one side, he determined that previous tracking measures were inadequate, resulting in a gross undercounting.
NASA’s Jet Propulsion Laboratory has completed the first comprehensive high-resolution topographic map of Central America, a region where persistent cloud cover had made high-quality satellite imagery difficult to obtain. A mosaic image created from the map, which was collected during the 2000 Shuttle Radar Topography Mission, is available on the JPL Planetary Photojournal at: