Whales that beach themselves in large groups are not all members of the same family, a study has found, undermining long-held assumptions about the cause of mass strandings.

An international team of scientists studied 12 mass strandings in Australia and New Zealand to examine the theory that healthy whales beach themselves while trying to help sick or disorientated family members who have run aground.

The European Space Agency (ESA) said it signed a deal on Thursday with its Russian counterpart to launch two unmanned missions to Mars, a quest that was rocked by a U.S. pullout last year.

Called ExoMars, the scheme entails sending an orbital probe to the Red Planet in January 2016 to look for atmospheric traces of methane gas, a pointer to the existence of microbial life.

In its exuberant childhood, the Universe created galaxies that were vast star-making machines, astronomers reported on Wednesday.

Using a brand-new telescope in Chile's Atacama desert, the team snared light that took more than 12 thousand million years to reach them.

The world's biggest radio telescope is being launched in a plateau high above Chile's Atacama desert.

The Atacama Large Millimeter/submillimeter Array, or ALMA, will search for clues about the dawn of the cosmos — from the coldest gases and dust where galaxies are formed to the energy produced by the Big Bang.

Scientists said Wednesday they had unravelled the genetic code of the tapeworm, unearthing data that should lead to more efficient drugs against the dangerous intestinal parasite.

Tapeworms are among the first known parasites of humans, recorded by Hippocrates and Aristotle as long ago as 300 BC.

Scientists used an iPhone and a camera lens to diagnose intestinal worms in rural Tanzania, a breakthrough that could help doctors treat patients infected with the parasites, a study said on Tuesday.

Research published by the American Journal of Tropical Medicine and Hygiene showed that it is possible to fashion a low-cost field microscope using an iPhone, double-sided tape, a flashlight, ordinary laboratory slides and an $8 cameral lens.

Neanderthals' bigger eyes and bodies meant they had less brain space to dedicate to social networking, which may explain why they died out and Homo sapiens conquered the planet, a study said Wednesday.

An enigmatic branch of the human family tree, Neanderthals lived in parts of Europe, Central Asia and Middle East for up to 300,000 years but vanished from the fossil record about 30-40,000 years ago.

In a super-arid desert at an altitude of 5,000 meters, with almost no humidity or vegetation, the world's largest ground-based astronomy project opens for business Wednesday ready to probe the universe with unprecedented might.

"What is so very special about this place is that, right here above our heads, there is virtually no water vapor. There is just so little that whatever light is emitted from a heavenly body, galaxy or star, it gets here with no interference" explained Gianni Marconi, an astronomer with the Atacama Large Millimeter-submillimeter Array, better known as ALMA (Spanish for "soul").

The body of "Lonesome George," a giant Galapagos tortoise once believed to be the last of its kind, has been sent to New York to be embalmed and then returned home, the Galapagos National Park said Tuesday.

A rare Pinta Island giant tortoise, George died June 24, 2012 at an estimated 100 years of age.

Analysis of Mars rocks by the Curiosity rover uncovered the building blocks of life -- hydrogen, carbon and oxygen -- and evidence the planet could once have supported organisms, NASA said Tuesday.

"A fundamental question for this mission is whether Mars could have supported a habitable environment," Michael Meyer, lead scientist for NASA's Mars Exploration Program said. "From what we know now, the answer is yes."