In the very last second before liftoff Sunday, SpaceX scrubbed the launch of its Falcon 9 rocket to send a communications satellite into orbit, marking the third delay since last week.

A fuel problem forced the sudden delay, following a postponement -- known as a hold -- earlier in the evening due to a ship that ventured into the waters off Cape Canaveral, Florida, said SpaceX CEO Elon Musk.

The sun-powered plane Solar Impulse 2 has made a successful test flight in Hawaii, where it has been grounded for repairs on its round-the-world trek, the Swiss-based project said Saturday.

"The first Solar Impulse 2 maintenance flight took place on Friday 26 of February (and) was uneventful. The plane took off from Kalaeloa airport at 4:32PM UTC [GMT] with our test pilot, Markus Scherdel, in the cockpit, and landed at 6:05PM UTC," it said on its blog.

An Australian icebreaker that ran aground in Antarctica during a blizzard has been refloated, officials said Saturday as they work to bring the vessel's expeditioners home.

The Aurora Australis ran aground with 68 people on board after breaking its moorings on Wednesday and was stuck on rocks at Horseshoe Harbor, close to Australia's Mawson station.

The monarch butterfly population has soared in its Mexican winter sanctuary this season, marking a recovery for the threatened species that migrates across North America, officials said Friday.

The orange and black butterfly covered 4.01 hectares (9.9 acres) of pine and fir forest in the 2015-2016 season, more than tripling last year's figure of 1.13 hectares, Mexican, U.S. and Canadian officials said.

Populations of bees, butterflies and other species important for agricultural pollination are declining, posing potential risks to major world crops, a U.N. body on biodiversity said Friday.

"Many wild bees and butterflies have been declining in abundance, occurrence and diversity at local and regional scales in Northwest Europe and North America," said an assessment by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).

An endangered tiger was shot dead by security forces in eastern Myanmar Thursday after it attacked local fishermen as they tended their nets, the state military newspaper reported.

Soldiers and local authorities hunted the animal "to prevent danger to villagers" after it mauled the two men in the early hours of the morning, the army's Myawaddy paper said in a post on its Facebook page.

Toddlers can figure out how to make and use simple tools without being taught, said a study Wednesday that defies conventional wisdom and earlier research.

Humans are unique in their capacity to design and wield sophisticated tools, but it has been widely assumed that such skills are passed down through imitation and learning.

NASA has received a record 18,300 resumes from people keen on becoming astronauts, the U.S. space agency said Friday.

The number of applications for a spot in NASA's 2017 class is almost triple the amount that came in during the last recruitment call for the 2012 class.

Visitors are rare these days to the museum of Russia's Space Research Institute in Moscow even though it holds gems like the model of the Soviet Lunokhod, the first ever space rover to land on the Moon, in 1970.

While the Cold War space race fired such cutting-edge projects, Russia's planetary exploration has stalled for the past three decades -- until now.

Japan successfully launched a jointly developed space observation satellite on Wednesday tasked with studying mysterious black holes, the country's space agency said. 

The ASTRO-H satellite, developed in collaboration between the agency, NASA and other groups, is set to orbit at an altitude of about 580 kilometres (360 miles) and observe X-rays emanating mainly from black holes and galaxy clusters.