Sky-watchers reported on Wednesday that a small planet in deep space that triggered one of the fiercest controversies in modern astronomy appears to be a colder "twin" of Pluto.

The study, published in the journal Nature, is the biggest probe into the enigmatic planet known as Eris, whose discovery in 2005 raised questions about the Kuiper Belt, a zone of icy objects beyond the orbit of Neptune.

As the global population hits seven billion, experts are warning that skewed gender ratios could fuel the emergence of volatile "bachelor nations" driven by an aggressive competition for brides.

The precise consequences of what French population expert Christophe Guilmoto calls the "alarming demographic masculinization" of countries such as India and China as the result of sex-selective abortion remain unclear.

Iceland and France are looking into the possibility of taking French trees endangered by global warming and planting them in Iceland to safeguard them for the future, officials said.

"The main emphasis (in the collaboration) is on research and finding ways to ensure the protection and preservation of the DNA... of the trees in Iceland," Adalsteinn Sigurgeirsson of the Icelandic Forestry Service told Agence France Presse.

New infrared observations from NASA telescopes have revealed how the first supernova ever recorded occurred and how its shattered remains ultimately spread out to great distances.

The U.S. space agency said Monday its Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) had solved a mystery dating from 2,000 years ago when Chinese astronomers witnessed what turned out to be an exploding star.

A Soyuz rocket lifted off on Friday on its maiden flight from Europe's space base here, carrying the first two satellites in the Galileo geopositioning system, an Agence France Presse reporter saw.

The launch -- the first by the veteran rocket beyond Russia's historic bases at Plesetsk and Baikonur -- is part of a commercial deal struck in 2003 to extend the range of Arianespace, which markets services from the European Space Agency (ESA) base in Kourou.

NASA on Wednesday set October 28 for its planned launch of a satellite to help weather forecasters predict extreme storms and offer scientists a better view of climate change.

The 1.5 billion dollar National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) is the first to measure both short and long term changes in weather and climate, the U.S. space agency said.

A retired satellite is hurtling toward the atmosphere and pieces of it could crash into the Earth as early as Friday, the German Aerospace Center says.

Scientists are no longer able to communicate with the dead German satellite ROSAT, which orbits the earth every 90 minutes, and experts are not sure exactly where pieces of it could land.

Europe's top court says patents cannot be filed on stem-cell research using cells from human embryos, a move many scientists say will harm future advances in medicine.

In a decision issued on Tuesday, the European Court of Justice in Luxembourg wrote that a process that involves taking a stem cell from a human embryo, resulting in its destruction, cannot be patented.

A South Korean team led by disgraced stem cell scientist Hwang Woo-suk is claiming to have cloned coyotes for the first time.

The Sooam Biotech Research Foundation said Monday that eight coyotes were born in June as part of its efforts to clone various species of animals in cooperation with South Korea's Gyeonggi Province.

The gleaming green schooner in Bremen's shipyard says everything about how Greenpeace has grown up through the years.

Three decades ago Greenpeace acquired a converted fishing trawler for $40,000, painted it green and set out to bump hulls with Japanese whalers and disrupt nuclear weapons testing; the first Rainbow Warrior was sunk by French intelligence agents in 1985.