Russia's defense ministry is looking to buy five dolphins, the government revealed on Wednesday, as the country strives to revive its Soviet-era use of sea mammals for military tasks. 

The military has opened the bidding on a 1.75 million ruble ($24,000) contract to deliver dolphins to the military in the Crimean port city of Sevastopol by August 1, according to a document uploaded Wednesday to the government's procurement website. 

Finnish authorities are investigating a mysterious "highly exceptional" spike in levels of radioactive cesium-137 detected over Helsinki, officials said Tuesday.

Nuclear safety regulator STUK said that while the radioactive surge last week posed no danger to human health, it was keen to get to the bottom of the cause.

Koalas and kangaroos are subject to more scientific study than Australia's twitching rodents and bats, according to new research which finds 'ugly' animals attract less funding and investigation.

The bias towards more attractive creatures means that while 'ugly' animals make up 45 percent of Australia's native fauna, they are rarely subject to intense scientific scrutiny, said a study to be published in Mammal Review this week.

Scientists have discovered a "ghostlike" octopus in deep water off Hawaii that appears to belong to a previously unknown species, researchers said.

A submersible research craft spotted the small, translucent octopus by chance around 2.5 miles (4 kilometers) underwater off Necker Island on the northwestern end of the Hawaiian Archipelago, the US National Oceanic and Atmospheric Administration (NOAA) said.

Scientists say they have discovered what might be a new species of octopus while searching the Pacific Ocean floor near the Hawaiian Islands.

On Feb. 27, a team found a small light-colored octopus at a depth of about 2.5 miles in the ocean near Necker Island, said Michael Vecchione of the National Oceanic and Atmospheric Administration. The octopus did not have fins and all of its suckers were in one row on each arm, Vecchione said.

U.S. astronaut Scott Kelly said Friday he is battling fatigue and super-sensitive skin, but is back to his normal height after nearly a year in space.

Kelly's 340-day mission -- spent testing the effects of long-term spaceflight ahead of a future mission to Mars, along with Russian cosmonaut Mikhail Kornienko -- wrapped up early Wednesday when they landed in frigid Kazakhstan aboard a Soyuz spacecraft.

A recent, 14-year dry spell in the Middle East was the worst drought in the past 900 years, according to a new NASA study released this week.

NASA's researchers examined records of rings of trees in several Mediterranean countries to determine patterns of dry and wet years across a span of 900 years. They concluded that the years from 1998 to 2012 were drier than any other period, and that the drought was likely caused by humans.

Conservation group Greenpeace warned on Friday that the environmental impact of the Fukushima nuclear crisis five years ago on nearby forests is just beginning to be seen and will remain a source of contamination for years to come.

The March 11, 2011 magnitude 9.0 undersea earthquake off Japan's northeastern coast sparked a massive tsunami that swamped cooling systems and triggered reactor meltdowns at the Fukushima Daiichi nuclear plant.

Social media sites such as Facebook and Instagram are increasingly being used in Asia as platforms for the illegal trade in threatened species ranging from rare birds to orangutan and sun bears, conservation groups said Thursday.

The trend poses a new and worrying threat in a tech-savvy region where products derived from endangered species are sought for traditional medicines and exotic animals are prized as pets, said wildlife-trade monitor Traffic and conservation group WWF.

U.S. astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko returned to Earth Wednesday after spending almost a year in space in a ground-breaking experiment foreshadowing a potential manned mission to Mars.

The 340-day mission saw Kelly break the record for the longest single stay in space by a U.S. astronaut, while Kornienko is now fifth on the list for lengthiest mission by a Russian cosmonaut.