Nearly 50 years ago, scientists found bones of two large, powerful dinosaur arms in Mongolia and figured they had discovered a fearsome critter with killer claws.

Now scientists have found the rest of the dinosaur and have new descriptions for it: goofy and weird.

North Americans, get set for the fourth and final eclipse of the year.

On Thursday, most of North America will have prime viewing of a partial solar eclipse. The new moon will hide part of the sun from view. The eclipse will unfold slowly following its start near the Kamchatka Peninsula in far eastern Russia.

An Italian lab has cooled a cubic meter of copper to within a tiny fraction of "absolute zero", setting a world record, the National Nuclear Physics Institute said Tuesday.

"The cooled copper mass... was the coldest cubic meter in the universe for over 15 days," the INFN said on its website.

China will launch its latest lunar orbiter in the coming days, state media said Wednesday, in its first attempt to send a spacecraft around the moon and back to Earth.

The spacecraft, which has not been named, will launch between Friday and Sunday, China's official Xinhua news agency reported.

The soaring, grimy chimneys of the coal-fired power station have belched the last of their choking fumes into Beijing's air, authorities say -- but experts doubt the plan will ease the capital's smog.

The 50-year-old Gaojing facility is one of four enormous generating plants authorities promised to close after the city was repeatedly blanketed by acrid haze.

Last month was the hottest September for globally averaged temperature over land and ocean surfaces since record-keeping began in 1880, the U.S. government said on Monday.

Not only did the month continue an ongoing trend of warming that has concerned scientists and environmentalists, it also marked the 38th consecutive September with a global temperature above the 20th century average, said the National Oceanic and Atmospheric Administration.

A Utah man who pleaded guilty in the theft of a priceless fossilized dinosaur footprint that's never been recovered was sentenced Monday to a year of probation and ordered to pay $15,000 in restitution.

Jared Ehlers, 35, in February pried a piece of sandstone with an ancient three-toed dinosaur track from a trail for off-road vehicles near Moab in southeastern Utah, federal prosecutors say.

The U.N.'s climate chief urged country negotiators Monday to "build bridges" at talks in Bonn towards a new, global pact that received fresh endorsement from world leaders last month.

The six-day forum must lay the foundations for the annual round of ministerial-level U.N. talks to be held in Lima in December, Christiana Figueres told delegates as the meeting opened.

It may not have been love as we know it, but around 385 million years ago, our very distant ancestors -- armored fish called placoderms -- developed the art of intercourse.

So suggest a team of evolutionary scientists, who point to the fossil of a placoderm species blessed with the name of Microbrachius dicki.

A comet the size of a small mountain whizzed past Mars on Sunday, dazzling space enthusiasts with the once-in-a-million-years encounter.

The comet, known as Siding Spring (C/2013 A1), made its closest encounter with Mars on Sunday at 2:27 pm (1827 GMT), racing past the Red Planet at a breakneck 126,000 miles (203,000 kilometers) per hour.