NASA launched its Interstellar Boundary Explorer, or Ibex, into orbit today for an examination of the solar winds that shield the Earth from harmful cosmic rays.

Ibex will give scientists a better understanding of how the solar wind -- made of magnetically charged particles -- interacts with the larger galaxy. The winds have fallen to the weakest level in half a century.

Much as the Earth's magnetic field repels cosmic rays, the solar wind protects the entire solar system. Ions, expelled by the sun in every direction at 1 million miles (1.6 million kilometers) per hour, create a ''bubble.'' This shield screens 90 percent of the intense, stellar radiation pulsing throughout the galaxy, said the National Aeronautics and Space Administration.

NASA's attempt to revive the ailing Hubble Space Telescope has hit a snag, leaving the iconic observatory's return to science observations in limbo until two new glitches can be solved, agency officials said Friday.

The new issues cropped up on Thursday while engineers were attempting to switch Hubble to a backup data relay channel and restore the telescope's ability to beam images and data back to Earth following a hardware failure last month.

"We think the soonest that we would be back doing full science would be sometime late next week," said Art Whipple, chief of NASA's Hubble systems management office at Goddard Space Flight Center in Greenbelt, Md., in a Friday teleconference.

Researchers at the Sudbury Neutrino Observatory say they have developed a new technique in the search for dark matter, the invisible substance or group of substances that make up a large percentage of the universe.

The Picasso group, made up of researchers from Canada, the United States and Czech Republic, said the new method will clear out background noise from other particles to give detectors a better shot at finding dark matter signals.

Dark matter is an important part of our picture of the universe - its gravitational influence helps explain why stars at the edges of galaxies appear to move at the same speed as those near the centre, for example.

Researchers at the University of Washington are working to reroute brain signals in an effort to give paralyzed people the ability to move their limbs again.

By creating an artificial connection between nerve cells in the brain and muscles, scientists say they are restoring voluntary movement to the once-paralyzed limbs, according to a report from the University of Washington in Seattle. The rerouting effectively bypasses damaged nerves in subjects with spinal cord injuries, which generally damage nerves but leave muscles and brain tissue unharmed.

Research that involves making new connections in living brains and even connecting robots to living brains has been gaining a lot of attention in the past year.

Cape Canaveral, FL - Science observations aboard the Hubble Space Telescope were on hold on Friday following a pair of problems that cropped up as the observatory recovered from a computer failure, NASA said.

Engineers successfully switched Hubble to a backup computer on Thursday and were watching as the telescope's instruments were automatically reactivating.

However on Friday NASA posted a notice on its website saying "the activation of the telescope's science instruments and resumption of observations has been suspended following two anomalies seen in systems on the telescope Thursday."

A news conference was planned for later on Friday.

While an international seed bank in a Norwegian island has been gathering news about its agricultural collection, a group of U.S. scientists has just published an article outlining a different kind of seed bank, one that proposes the gathering of wild species - - at intervals in the future - - effectively capturing evolution in action.

In the October issue of Bioscience, Steven J. Franks of Fordham University, Susan J. Mazer of the University of California, Santa Barbara, and a group of colleagues, have proposed a method of collecting and storing seeds of natural plant populations. They argue for the collection of many species in a way that evolutionary responses to future changes in climate can be detected. They call it the "Resurrection Initiative."

"In contrast to existing seed banks, which exist primarily for conservation, this collection would be for research that would allow a greater understanding of evolution," said Franks.

"This seed collection would form an important resource that can be used for many types of research, just as GenBank - - the collection of genetic sequences and information - - forms a key resource for research in genetics and genomics," said Franks.

"Typically, seed banks are focused on the preservation of agricultural species or other plant species of strong economic interest, say, forest species, forest trees," said Mazer. This is to make sure that scientists can maintain a genetically diverse seed pool in the event of some kind of ecological calamity that requires the replenishing of seeds from a certain part of the world or from certain species. "But that implies a relatively static view of a seed bank, a snapshot forever of what a species provides."

According to legend, Genghis Khan lies buried somewhere beneath the dusty steppe of Northeastern Mongolia, entombed in a spot so secretive that anyone who made the mistake of encountering his funeral procession was executed on the spot.

Once he was below ground, his men brought in horses to trample evidence of his grave, and just to be absolutely sure he would never be found, they diverted a river to flow over their leader's final resting place.

What Khan and his followers couldn't have envisioned was that nearly 800 years after his death, scientists at UC San Diego's Center for Interdisciplinary Science in Art, Architecture and Archaeology (CISA3) would be able to locate his tomb using advanced visualization technologies whose origins can be traced back to the time of the Mongolian emperor himself.

Astronomers think that many - perhaps all - galaxies in the universe contain massive black holes at their centers. New observations with the Submillimeter Array now suggest that such colossal black holes were common even 12 billion years ago, when the universe was only 1.7 billion years old and galaxies were just beginning to form.

The new conclusion comes from the discovery of two distant galaxies, both with black holes at their heart, which are involved in a spectacular collision.

4C60.07, the first of the galaxies to be discovered, came to astronomers' attention because of its bright radio emission. This radio signal is one telltale sign of a quasar - a rapidly spinning black hole that is feeding on its home galaxy.

When 4C60.07 was first studied, astronomers thought that hydrogen gas surrounding the black hole was undergoing a burst of star formation, forming stars at a remarkable rate - the equivalent of 5,000 suns every year. This vigorous activity was revealed by the infrared glow from smoky debris left over when the largest stars rapidly died.

About three times a second, a 10,000-year-old stellar corpse sweeps a beam of gamma-rays toward Earth. This object, known as a pulsar, is the first one known to "blink" only in gamma rays, and was discovered by the Large Area Telescope (LAT) onboard NASA's Fermi Gamma-ray Space Telescope, a collaboration with the U.S. Department of Energy (DOE) and international partners.

"This is the first example of a new class of pulsars that will give us fundamental insights into how stars work," says Stanford University's Peter Michelson, principal investigator for the LAT. The LAT data is processed by the DOE's Stanford Linear Accelerator Center and analyzed by the International LAT Collaboration.

In a little more than two years, the last Internet addresses will be assigned by the international group tasked with managing the 4.3 billion numbers. And yet, while most Internet engineers are looking to Internet Protocol version 6 (IPv6), the next-generation Internet addressing scheme, a research team has probed the entire Internet and found that the problem may not be as bad as many fear. The probe reveals millions of Internet addresses that have been allocated but remain unused.

In a paper to be presented later this month at the Proceedings of the ACM Internet Measurement Conference, a team of six researchers have documented what they claim is the first complete census of the Internet in more than two decades. They discovered a surprising number of unused addresses and conclude that plenty will still be lying idle when the last numbers are handed out in a few years' time. The problem, they say, is that some companies and institutions are using just a small fraction of the many million addresses they have been allocated.