China said it successfully launched an unmanned spacecraft on Tuesday to carry out a key docking mission, taking its next step towards the goal of building its first space station by 2020.

The Shenzhou VIII blasted off from the Gobi desert in China's northwest at 5:58 am (2158 GMT) before separating from its carrier rocket about 200 kilometers (120 miles) above the Earth, the state Xinhua news agency said.

After a years-long delay, an Earth-observing satellite blasted into space early Friday on a dual mission to improve weather forecasts and monitor climate change.

A Delta 2 rocket carrying the NASA satellite lifted off shortly before 3 a.m. from the central California coast. The satellite separated from the rocket about an hour after launching, unfurled its solar panels and headed toward an orbit 500 miles above Earth.

A prominent physicist and skeptic of global warming spent two years trying to find out if mainstream climate scientists were wrong. In the end, he determined they were right: Temperatures really are rising rapidly.

The study of the world's surface temperatures by Richard Muller was partially bankrolled by a foundation connected to global warming deniers. He pursued long-held skeptic theories in analyzing the data. He was spurred to action because of "Climategate," a British scandal involving hacked emails of scientists.

Japan and India are moving forward on a deal for Tokyo to provide nuclear plant technology to India despite widespread worries about safety after the March 11 disaster triggered by a massive tsunami.

Japanese Foreign Minister Koichiro Gemba told reporters Saturday that the agreement was reached in a meeting in Tokyo with his Indian counterpart S.M. Krishna to move forward on the nuclear plant deal.

The Fukushima nuclear disaster released twice as much of a radioactive substance into the atmosphere as Japanese authorities estimated, reaching 40 percent of the total from Chernobyl, a preliminary report says.

The estimate of much higher levels of radioactive cesium-137 comes from a worldwide network of sensors.

In the harsh, remote wilds of the Canadian tundra, a wolverine scampers up to a polar bear snoozing near the shore of the Hudson Bay. The bear rises and makes a half-hearted charge, driving away the fierce, badger-like animal.

The brief encounter Thursday was streamed live to computers around the world through a new program that aims to document in real time the annual migration of hundreds of polar bears outside Churchill, Manitoba.

A rare opportunity to observe an asteroid at close quarters has unveiled a remarkable rock that seems to be a precursor of a planet, astronomers reported on Thursday.

"This is the first object of this kind we have ever seen," Stephane Erard of the Paris Observatory told Agence France Presse.

Under the auspices of President Michel Suleiman, the Arab Forum for Environment and Development held its annual conference Thursday at the Habtoor Grand Hotel where it stressed how green energy can lift the economy in the Arab world.

Environment Minister Nazem al-Khoury represented Suleiman at the conference which was attended by more than 20 parliament members, as well as around 500 delegates from Arab and international countries.

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.