Space

Cause of Mercury's magnetic field proposed

Champaign,Iii -- U.S. scientists say they've determined convection currents inside Mercury's core create that planet's weak magnetic field.

The field, discovered during the 1970's by NASA's Mariner 10 spacecraft, is about 100 times weaker than Earth's magnetic field.

Researchers at the University of Illinois and Case Western Reserve University in Cleveland have produced a model of conditions within Mercury's core that give rise to that weak magnetic field.

Although mostly made of iron, Mercury's core also contains sulfur. The scientists subjected an iron-sulfur mixture in a laboratory to pressures and temperatures similar to those expected to exist within Mercury. When they analyzed the mixture with a scanning electron microscope, they found the iron atoms had condensed into flakes.

Interior of Mars is colder than thought

Pasadena, Calif -- New data from the U.S. space agency's Mars Reconnaissance Orbiter suggest the crust and upper mantle of Mars is stiffer and colder than thought.

National Aeronautics and Space Administration scientists said the findings suggest any liquid water existing beneath that planet's surface -- and any possible organisms in the water -- would be located deeper than scientists had suspected.

"We found that the rocky surface of Mars is not bending under the load of the north polar ice cap," said Roger Phillips of the Southwest Research Institute in Boulder, Colo. "This implies that the planet's interior is more rigid, and thus colder, than we thought before."

Scientists at NASA's Jet Propulsion Laboratory, which manages the Orbiter mission, said radar images show a smooth, flat border between the ice cap and the rocky Martian crust. On Earth, the weight of a similar amount of ice would cause the planet's surface to sag. The fact the Martian surface is not bending means its strong outer shell -- or lithosphere, a combination of its crust and upper mantle -- must be very thick and cold, they said.

ESA opens satellite navigation competition

Paris -- The European Space Agency's fifth annual European Satellite Navigation Competition is seeking ideas for satellite navigation usage in non-space businesses.

The ESA said the competition is designed as a catalyst for new, high-tech industry in Europe. Since the competition began in 2004, 650 ideas on how to use satellite navigation have been presented. In 2007, more than 250 proposals were submitted from across Europe.

For 2008, the ESA said the winner will receive direct support at one of the three ESA business incubation centers located in the Netherlands, Germany and Italy. The winner will be assisted by ESA's top experts and have access to space technologies.

The competition that runs from May 1 to July 31 is open to companies, entrepreneurs, research institutes, universities and individuals from around

The molecule hydroxyl is detected on Venus

Paris -- The European Space Agency said the molecule hydroxyl has been detected on another planet for the first time by its Venus Express spacecraft.

The ESA said hydroxyl, an important but difficult-to-detect molecule, consists of one hydrogen and one oxygen atom. It was detected in the upper reaches of the Venusian atmosphere, approximately 60 miles above the surface, by Venus Express's Visible and Infrared Thermal Imaging Spectrometer, or VIRTIS.

Scientists said the molecule was discovered by turning the spacecraft away from the planet and looking along the faintly visible layer of atmosphere surrounding the planet's disc. The instrument detected the hydroxyl molecules by measuring the amount of infrared light they produce.

Venus Express showed the amount of hydroxyl at Venus is highly variable. It can change by 50 percent from one orbit to the next, possibly caused by differing amounts of ozone in the atmosphere.

NASA names competition winners

Washington -- The U.S. space agency has announced the winners of its high school competition to describe the passenger and cargo aircraft of the future.

Tom Neuman, a senior from George Walton Comprehensive High School in Marietta, Ga., and Aditya Singh, a senior from the Anglo-Chinese Junior College in Singapore, won top individual prizes for essays about their concepts of multi-functional personal air vehicles.

More than 140 teenagers from 50 schools across the United States and 15 other nations submitted 65 entries in four categories: U.S. individual, U.S. team, non-U.S. individual and non-U.S. team.

The top teams were three 11th-graders from West High School in Torrance, Calif., and three ninth-graders from the National High School of Computer Science in Bucharest, Romania.

Two astronauts are assigned to the ISS

Washington -- The U.S. space agency and its international partners say they have assigned two crew members to the Expedition 20 International Space Station mission.

National Aeronautics and Space Administration astronaut Timothy Creamer and Japan Aerospace Exploration Agency astronaut Soichi Noguchi will travel on a Russian Soyuz spacecraft in November 2009. Creamer, a U.S. Army colonel, will be making his first trip to space.

Creamer and Noguchi will join the Expedition 20 mission in progress and remain aboard the space station for six months. Other members of the Expedition 20 crew have yet to be selected.

The Expedition 20 crew will continue assembly of the station as well as outfitting the orbiting complex with spare parts and supplies.

Crew members named as backups are NASA astronaut and Army Col. Douglas Wheelock, and JAXA astronaut Satoshi Furukawa.

Satellite may help explore ancient Mexico

Rochester, N.Y. -- A U.S. archeologist plans to use National Aeronautics and Space Administration satellite imagery to study ancient Mexico.

Professor Bill Middleton of the Rochester Institute of Technology said he plans to use multi- and hyperspectral data to build the most accurate and most detailed landscape map extant of the southern state of Oaxaca, where the Zapotec people formed the first state-level and urban society in Mexico.

"If you ask someone off the street about Mexican archeology, they'll say Aztec, Maya. Sometimes they'll also say Inca, which is the wrong continent, but you'll almost never hear anyone talk about the Zapotecs," said Middleton. "They had the first writing system, the first state society, the first cities. And they controlled a fairly large territory at their zenith (250 B.C. to A.D. 750)."

Study: Climate change is altering Earth

New York -- A U.S. space agency study shows human-caused climate change is altering many of Earth's natural systems, including permafrost, plants and lakes.

Cynthia Rosenzweig of the National Aeronautics and Space Administration's Goddard Institute for Space Science -- along with scientists at 10 other institutions -- say they have linked physical and biological impacts since 1970 with rises in temperatures during that period.

The study concludes human-caused warming is resulting in a broad range of impacts around the globe.

"This is the first study to link global temperature data sets, climate model results and observed changes in a broad range of physical and biological systems to show the link between humans, climate and impacts," said Rosenzweig, lead author of the study.

Another supernova discovered in Milky Way

Washington -- The U.S. space agency says its Chandra X-ray Observatory and the National Radio Astronomy Observatory have found the most recent supernova in the Milky Way.

The National Aeronautics and Space Administration said the discovery, made by tracking the rapid expansion of the supernova's remains, will help the understanding of how often supernovae explode in the Milky Way galaxy.

NASA said the supernova explosion occurred about 140 years ago, making it the most recent in the Milky Way. Previously, the last-known supernova in our galaxy occurred around 1680 -- an estimate based on the expansion of its remnant, Cassiopeia A.

Astronomers said finding such a recent, obscured supernova is a step toward making better estimates of how often the stellar explosions occur. That's important, they said, because supernovae can result in the formation of new stars as part of a cycle of stellar death and rebirth. The explosion also can leave behind, in addition to its expanding remnant, a central neutron star or black hole.

NASA announces educational TV partnership

San Jose, Calif -- The U.S. space agency says it has launched a partnership with the National Institute of Aerospace to produce educational television programs.

National Aeronautics and Space Administration Deputy Administrator Shana Dale said the TV programs will be available on NASA Television and the Internet.

The announcement was part of Dale's keynote address Wednesday in San Jose, Calif., during the NASA Future Forum.

Dale said the partnership is designed to engage young people in the excitement and challenges the future holds for America's space program.

Designed for grades K-12 and young adults, the short video snippets will be available on demand through the Internet during the 2008 and 2009 school years.

NASA said elementary school-level segments will provide a balanced introduction to the fields of science and engineering and be aligned to national education standards, while middle school-level segments will detail the relevance of math to 21st century careers. The high school-level segments will build on the engineering and science behind NASA projects and missions.

Insulation is NASA's 2007 best invention

Moffet Field, Calif -- The U.S. space agency says its 2007 Government Invention of the Year is a heat shield insulation material.

The National Aeronautics and Space Administration said the lightweight ceramic ablator, or LCA, material is slightly denser than balsa wood and is designed to protect a spacecraft during its fiery re-entry into Earth's atmosphere.

The LCA is a low-density material that weighs one-fifth as much as conventional heat shields, but can withstand temperatures up to 5,000 degrees Fahrenheit, according to NASA project engineers. The material has a foundation made of fibers coated with a thin layer of organic polymeric resin. The resin, traditionally used as a bonding agent, creates a light, durable, heat-resistant shield.

NASA puts 'finishing touches' on GLAST

Cape Canaveral, Fla. -- The U.S. space agency said it is putting the "finishing touches" on its Gamma-ray Large Area Space Telescope, or GLAST, which is to be launched June 3.

Scientists at the Cape Canaveral Air Force Station, near the Kennedy Space Center, are supervising the installation of such equipment as sun shades and thermal blankets.

"Sun shades are like a visor you flip down in your car on a sunny day to block the sun's glare so you can see the road," said Steve Ritz, GLAST project scientist. They "shade" the spacecraft's optical instruments from stray light coming from the sun, the Earth and the moon.

Once the shades are installed, temporary covers are placed on the open part of the shades to protect the optics from debris. The covers are removed after the rocket fairing -- the shell of the rocket where GLAST will be located -- is installed on the launch vehicle prior to flight.