Protection for moon, Mars astronauts eyed
DARMSTADT, Germany, Sept. 18 (UPI) -- Rocks on the Earth's moon or on Mars could be used to build shelters to possibly protect astronauts from dangerous cosmic radiation, European researchers say.
German scientists working with the European Space Agency have tested how well stone slabs can protect against radiation, a release from the GSI Helmholtz Center for Heavy Ion Research said Monday.
The findings are important because astronauts would be more exposed to radiation because neither a magnetic field nor a thick atmosphere protects them on the moon or Mars, and ground stations would not be built from terrestrial materials that might offer protection, researchers said.
"In space travels every gram counts. Transporting building material through space would lead to a cost explosion," GSI researcher Chiara La Tessa said.
"That is why ground stations would basically be built from moon and Mars regolith -- especially the shielding. We know from the analyses done by rovers what the local sand and stones consist of. With this information one can produce moon and Mars regolith on Earth and we test it for its properties."
GSI scientists conducted tests intended to see how far cosmic rays might pass through moon and Mars rock.
"I cannot estimate how the material is going to react to the radiation yet," La Tessa said. "This we will know when we [have] analyzed our experiment data."
Turkish dig yields large Roman mosaic
LINCOLN, Neb., Sept. 18 (UPI) -- A massive Roman mosaic unearthed in southern Turkey dates to the height of Roman influence in the region, a team led by U.S. archaeologists says.
Researchers from the University of Nebraska-Lincoln said the meticulously crafted, 1,600-square-feet of decorative handiwork is believed to be the largest mosaic of its type in the region.
It demonstrates the surprising reach and cultural influence of the Roman Empire in the area during the third and fourth centuries A.D., art history Professor Michael Hoff said.
"Its size signals, in no small part, that the outward signs of the empire were very strong in this far-flung area," he said in a university release Tuesday.
"We were surprised to have found a mosaic of such size and of such caliber in this region -- it's an area that had usually been off the radar screens of most ancient historians and archaeologists, and suddenly this mosaic comes into view and causes us to change our focus about what we think [the region] was like in antiquity."
The mosaic was discovered in the remains of the ancient city of Antiochia ad Cragum on the southern Turkish coast, founded in the middle of the first century.
"We're beginning to understand now that [the region] was more Romanized, more in line than the rest of the Roman world than was suspected before," Hoff said.
"[The nature of the mosaic] hammers home how Roman this city truly is."
Quasars help map the universe
CLEVELAND, Sept. 18 (UPI) -- U.S. researchers say they've found a possible way to map the spread and structure of the universe, using light from distant quasars as a "mapping" tool.
With the predicted discovery of millions more far-away quasars over the next decade, the technique could yield a view to shortly after the Big Bang, when the universe was a fraction the size it is today, they said.
"It appears we may have a useful tool for mapping out the expansion history of the universe," Case Western Reserve University physics Professor Glenn Starkman said.
Researchers discovered patterns of light variation over time in quasars linked to their redshift, a shift in the light frequency caused by the quasars moving away from Earth in the expansion of the universe.
Knowing the quasar redshift enables an estimate of the relative size of the universe when the light was emitted. The larger the redshift, the farther and older the light source.
"If we could measure the redshifts of millions of quasars, we could use them to map the structures in the universe out to a large redshift," Starkman said in a university release.
Very old and distant quasars have been measured with redshifts suggesting they emitted the light we are seeing today when the universe was as small as one-eighth the size it is today, the researchers said.
Extinct human species had hunting skills
SCHONINGEN, Germany, Sept. 18 (UPI) -- Discoveries at early Stone Age site in north-central Germany show previous species of humans were skilled hunters 300,000 years ago, scientists say.
Eight extremely well-preserved spears -- the oldest known weapons found anywhere -- along with other artifacts and animal remains found at the site suggest the spears' users were highly skilled craftsmen and hunters, well-adapted to their environment and possessed of a capacity for abstract thought and complex planning comparable to modern man, the researchers said.
Scientists from the University of Tubingen's Institute of Prehistory said that they were likely members of the species Homo heidelbergensis, although no human remains have been found at the site.
Excavations in an open coal mine in Schoningen since 2008 are providing insights into how humans lived in the environment of 300,000 years ago, a Tubingen release said.
The bones of large mammals -- elephants, rhinoceroses, horses and lions -- as well as the remains of amphibians, reptiles, shells and even beetles have been preserved in the coal along with the human artifacts, the researchers said.
