With space shuttles now housed in history museums, innovators in aerospace are thinking of newer, better ways humans could reach space. One idea: What about a space elevator?

This real idea is one simulation that's part of a new high-tech interactive exhibition about the future of flight opening Aug. 1 at the Smithsonian's National Air and Space Museum. The exhibit also will serve as an important test case for new technologies to overhaul the popular museum with more interactives.

Japan, the world's sixth biggest greenhouse gas polluter, has pledged to cut emissions 26 percent from 2013 levels by 2030, a target observers judged inadequate to avert calamitous global warming.

In order to achieve this goal, nuclear energy, deeply unpopular and offline since the 2011 tsunami-induced Fukushima disaster, must provide about 20-22 percent of electricity production by then, said the country's official UN filing late Friday.

Smooth, icy plains have been spotted on the surface of Pluto, in the latest images released Friday from a NASA spacecraft that flew by the dwarf planet this week.

The plains are located north of Pluto's icy mountains, in the center-left of the heart shape that NASA has named "Tombaugh Regio," or the Tombaugh Region after Clyde Tombaugh, who discovered Pluto in 1930.

A super-dense white dwarf star about 730 light years from Earth has been caught in the act of "cannibalizing" its companion, astronomers said Friday.

The pair form a binary star system named Gaia14aae after the European Space Agency's Gaia satellite which discovered it in August 2014.

Guatemalan security forces rescued 52 animals from endangered species, including several dozen macaws and some turtles, during a raid in which they arrested two alleged wildlife traffickers, an official said Thursday.

The animals were rescued from a construction company in the town of Amatitlan, just south of Guatemala City, national police spokesman Jorge Aguilar told reporters.

The pilots of a grounded solar-powered airplane say they put too much stress on the batteries of their aircraft as they were leaving Japan for a five-day record-breaking flight to Hawaii.

The pilots then discovered they had too much insulation around the batteries for them to adequately cool down during the flight through tropical skies.

Rampant illegal trading in ivory in Hong Kong is pushing elephants towards extinction, conservationists said Thursday, reporting more ivory items on sale there than in any other city.

The sale of ivory items from government-registered stockpiles predating the 1990 ban is allowed for domestic use in Hong Kong, but the report finds tusks from recently slaughtered elephants are being passed off as old ivory on a huge scale.

A Thai farmer was arrested Thursday after he confessed to erecting an electrified fence which killed three elephants close to a national park, police said.

The three pachyderms -- one male and two females -- were found dead on Wednesday near a village pond outside Kaeng Krachan national park in Prachuap Khiri Khan province.

The only surviving giant panda twins ever born in the U.S. are celebrating their second birthday.

Zoo Atlanta officials said Mei Lun and Mei Huan turned 2 on Wednesday and were given special treats in their habitats. They say the pair will be treated to ice cakes during a second celebration Saturday.

The sun-powered plane Solar Impulse 2 will be grounded for months in Hawaii to carry out battery repairs, after completing nearly half of an unprecedented round-the-world flight, the project said Wednesday. 

"Irreversible damage to certain parts of the batteries will require repairs which will take several months," it said in a statement.