Have no fear: The White House says an asteroid more than 1 1/2 miles (2.7 kilometers) long poses no threat to planet Earth.

The big rock called Asteroid 1998 QE2 was making its closest approach to Earth on Friday, keeping a safe distance of 3.6 million miles (5.8 million kilometers), or 15 times the distance between Earth and the moon.

A coral-killing starfish has begun infesting a channel of water in the Philippines famed for having some of the most diverse marine life in the world, the government said Friday.

The appearance of the crown-of-thorns starfish in the Verde Island Passage could cause great damage to the area's biodiversity, Jacob Meimban, head of the wildlife bureau's coastal marine management office, told Agence France Presse.

Astronauts who travel on future missions to Mars would likely be exposed to their lifetime limit of radiation during the trip, not to mention time spent on the Red Planet, scientists said Thursday.

The measurements were made aboard the Mars Science Laboratory, an unmanned NASA rover and mobile lab that set off for Mars in 2011 before landing 253 days later in August 2012, said the report in the U.S. journal Science.

The United Nations on Thursday warned overfishing in the Mediterranean was boosting jellyfish, which reduce stocks further and it called for jellyfish to be used in food, medicine and cosmetics.

A study by the U.N.'s Food and Agriculture Organisation (FAO) in Rome said overfishing had increased the number of jellyfish because it had removed their main predators from the food chain.

A British physicist and his Belgian colleague who all but identified the mysterious "God particle" that holds the universe together won a prestigious Spanish science prize on Wednesday.

Peter Higgs, 84, who gave his name to the Higgs Boson, an elusive subatomic particle, and Francois Englert, 80, won the Prince of Asturias science prize, one of a series of top annual awards.

Venerated for 150 years as the forebear of all birds until being relegated two years ago to the common class of winged dinosaurs, the Archaeopteryx was restored to its hallowed branch on the tree of life on Wednesday.

A fossil find in China proved the winged creature was in fact an ancestor of modern birds, said a study in the journal Nature.

Similar in size and often referred to as twin planets, Earth and Venus evolved from common origins into two contrasting worlds - one dry and inhospitable, the other wet and teeming with life.

The reason has had science stumped, until now.

Plants entombed under ice in Canada's far north for centuries have come back to life after exposure to air and sunlight, Canadian researchers have found.

University of Alberta researcher Catherine La Farge collected what she believed to be dead mosses (or bryophytes) from the foot of a retreating glacier in Sverdrup Pass on Ellesmere Island.

Russian scientists claimed Wednesday they have discovered blood in the carcass of a woolly mammoth, adding that the rare find could boost their chances of cloning the prehistoric animal.

An expedition led by Russian scientists earlier this month uncovered the well-preserved carcass of a female mammoth on a remote island in the Arctic Ocean.

An international trio flying in a Russian capsule docked with the International Space Station on Wednesday with a busy schedule full of space walks and an encounter with a pioneering U.S. cargo craft.

The six-month mission of Russian commander Fyodor Yurchikhin and his two flight engineers -- Karen Nyberg of NASA and Italian Luca Parmitano of the European Space Agency -- began once their craft sidled up to the orbiting lab six hours after blasting off from the Moscow-owned Baikonur space center in Kazakhstan.