Light Pierced "Dark Age" Fog

Because of the time it takes for light to travel such distances, scientists think the exploded star must have been born about 600 million years after the big bang, when the universe was just 4 percent of its current age.

This means that the gamma-ray burst offers an unprecedented peek into a mysterious period known as the cosmic dark ages, which lasted from shortly after the big bang until about 900 to 800 million years ago.

Astronomers think the first stars started forming during the dark ages. But few such stars have ever been spotted, because the early universe was fogged with hydrogen gas that shrouded the starlight.

"Our group, and many others worldwide, have been working for years to catch such a rare event," said Ruben Salvaterra of Italy's Brera Astronomical Observatory, who was lead author on one of the studies.

The discovery gives researchers hope of spotting still older objects, including the first generation of stars that ever formed.

"Gamma-ray bursts are the most luminous phenomena in the universe," said Dale Frail, whose team tracked radio emissions from the dying star using the National Radio Astronomy Observatory in Socorro, New Mexico. (See pictures of a gamma-ray burst that was visible from Earth to the naked eye.)

"This means that a bright gamma-ray burst could be detected out to the earliest times in the age of the universe."

Text Message From Space

The newfound gamma-ray burst, dubbed GRB 090423, was first picked up in April by sensors aboard a NASA satellite called Swift.

The probe instantly swiveled its mirrors to monitor the burst, and soon after astronomers worldwide received alerts.

Voices of long-dead stars haunt the galaxy

Mysterious radio blips that come from apparently empty regions of space may be the voices of long-dead stars.

Thirteen unexplained radio blips have turned up in radio telescope observations since the 1980s. They emerged in spots where there are no stars or galaxies to be seen, last anywhere from hours to days, and do not seem to repeat. The blips could be traces of a vast population of stellar corpses – neutron stars that roam the universe largely unseen, suggests a team led by Eran Ofek of the California Institute of Technology in Pasadena.

Most of the galaxy's estimated billion neutron stars are invisible. Some of the newly formed ones have been detected because their rapid rotation sends radio pulses our way multiple times per second. These are thought to fade with age.
If each of the neutron stars produces a radio burst every few months, perhaps after absorbing interstellar gas, the close ones would be detected at the rate observed, the team calculates.

"Neutron stars are a good possibility as the explanation for these events," says Geoffrey Bower of the University of California, Berkeley, whose team found seven of the outbursts in archived data from the Very Large Array telescope at the National Radio Astronomy Observatory near Socorro, New Mexico. "They are ubiquitous throughout the galaxy."

Bower and his colleagues plan to scrutinise the locations of the radio blips using the orbiting Chandra X-ray Observatory, looking for X-ray emissions characteristic of neutron stars.

Marine Machines Made in Nature's Image

If it looks like a fish and swims like a fish, it could be a robot--such as the University of Bath's Gymnobot (pictured), inspired by an Amazonian knifefish.

Researchers worldwide are developing robots that look and act like aquatic creatures. That's because biomimetic gadgets--bots that take inspiration from nature--are often more efficient than their clunkier counterparts.

"In a fishlike fish, the whole of the animal is muscle--its propeller," said Gymnobot developer William Megill of the University of Bath, U.K. "That's not particularly conducive to putting in circuit boards."

To allow more room for cameras and other electronics, Megill's team took cues from the knifefish, which keeps its body rigid to sense electric currents in the water. In the same way, Gymnobot uses its lower, bladelike "fin" to propel itself through the water while the body remains rigid.

Megill and colleagues hope the bot can be used to study marine life near the shore, where a propeller would kick up too much sediment or get tangled in weeds.

Controversy erupts over mock lunar lander contest

A rival team is crying foul after a competitor's mock lunar lander was allowed to make an extra flight, putting it in first place for a $1 million prize. But a spokesman for the X Prize Foundation, which organised the competition, said no rules were broken.

The Northrop Grumman Lunar Lander ChallengeMovie Camera is intended to promote innovative ideas for a new generation of vehicles that could land humans on the moon.

It is divided into two levels. For the lesser $350,000 level 1 prize, a rocket must rise 50 metres from its launch pad, move 100 metres horizontally and land on a concrete pad, staying in the air for a total of at least 90 seconds. It must then repeat the feat, returning to its starting point within 2.5 hours. Texas-based Armadillo Aerospace won that prize in October 2008.

To qualify for the $1 million level 2 prize, a rocket must make a similar flight, but this time it must stay aloft for 180 seconds and land on a bumpy surface that simulates that of the moon.

Armadillo became the first team to qualify for the prize in September.

But on Friday, Masten Space Systems of Mojave, California, was poised to wrest the prize from Armadillo, after making qualifying flights that outperformed its rival in landing accuracy.

While Armadillo's vehicle landed on average 90 centimetres from its target in the second-level tests, Masten's two Friday flights appeared to be only about 25 centimetres away, according to William Pomerantz of the X Prize Foundation. Judges have yet to release official numbers for the Masten flights.