Groundbreaking astrophysicist Vera Rubin, who confirmed that the bulk of the universe is made up of invisible dark matter, has died in Princeton, New Jersey aged 88.

"Vera Rubin was a national treasure as an accomplished astronomer and a wonderful role model for young scientists," said Matthew Scott, president of the Carnegie Institution for Science.

Cheetahs are "sprinting" to extinction due to habitat loss and other forms of human impact, according to a new study out this week which called for urgent action to save the world's fastest land animals.

Thousands were expected to gather Saturday in Ohio for a memorial service to pay tribute to American space legend John Glenn, who died last week at the age of 95. 

The year 2016 has seen a rekindling of the human desire to conquer Mars, with public and private interests openly vying to take the first step on the Red Planet, possibly with a stopover on the Moon.

Space-faring nations are mostly united in viewing Mars as the next frontier with many still pooling their money and expertise to make the dream a reality, despite souring relations between them.

Japan will launch a cargo ship Friday bound for the International Space Station, carrying a 'space junk' collector that was made with the help of a fishnet company. 

John Glenn, who made history twice as the first American to orbit the Earth and the first senior citizen to venture into space, has died at the age of 95, the Ohio State University college bearing his name said Thursday.

The former astronaut had been admitted more than a week ago to the university's James Cancer Hospital, according to the John Glenn College of Public Affairs.

Wild giraffe numbers have plummeted by 40 percent in the last three decades, and the species is now "vulnerable" to extinction, a top conservation body said Thursday.

The population of the world's tallest land mammal dropped to below 100,000 in 2015, mainly due to habitat loss and illegal hunting, the International Union for the Conservation of Nature (IUCN) reported.

Dark matter, the mysterious substance believed to comprise a quarter of our Universe, is spread out more smoothly than previously thought, said a study Wednesday that may challenge some tenets of physics.

Earth's days are getting longer but you're not likely to notice any time soon -- it would take about 3.3 million years to gain just one minute, according to a study published on Wednesday.

Authorities in Russia's Siberian region of Tuva on Monday were examining several pieces of the Progress cargo spaceship found after it crashed last week having failed to reach orbit.

Two pieces, including a large spherical object, were found by herders over the weekend, while another was discovered in the courtyard of a residential house on Monday, said the region's head Sholban Karaa-ool, warning people not to touch any metal debris.