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Are we in a sixth mass extinction?

This short video puts modern extinctions in context by comparing them with Earth’s 5 previous mass extinctions.

Image via NASA

Possible water plumes spotted on Europa

Water plumes erupting on Jupiter’s moon Europa might make it easier to investigate whether life exists in the warm ocean believed to be deep beneath its icy surface.


New theory on why time advances

Why does time flow inexorably toward the future? A Berkeley physicist proposes that time is expanding because space is expanding.

This view shows Saturn's northern hemisphere in 2016, as that part of the planet nears its northern hemisphere summer solstice in May 2017. Saturn's year is nearly 30 Earth years long, and during its long time there, Cassini has observed winter and spring in the north, and summer and fall in the south. The spacecraft will complete its mission just after northern summer solstice, having observed long-term changes in the planet's winds, temperatures, clouds and chemistry. Image via NASA JPL.

Cassini begins epic final year at Saturn

The spacecraft will plunge repeatedly between Saturn and its rings, and finally execute a headlong plummet into the body of Saturn itself.

A polar bear tests the strength of thin sea ice. Image via Mario Hoppmann/imaggeo.egu.eu

Melting sea ice leaves polar bears hungry

“Sea ice really is their platform for life. They are capable of existing on land for part of the year, but the sea ice is where they obtain their main prey.”


What if all of Earth’s ice melted?

What would Earth be like if all of its ice melted? New short video from the guys at AsapSCIENCE, featuring Bill Nye.

The image shows an area nicknamed the "Xanadu annex" by members of the Cassini radar team, earlier in the mission. Image via NASA/ JPL.

Glorious new images show Titan’s dunes

Cassini spacecraft will begin its grand finale at Saturn in 2017. This was one of Cassini’s last close flybys of Saturn’s large moon, Titan.


Brown dwarfs hiding in plain sight

Brown dwarfs are like stars, but too small to ignite fusion in their cores and so shine as stars do. If you saw one, it wouldn’t be brown. It’d be magenta.

NASA's Juno spacecraft captured this view as it closed in on Jupiter's north pole, about two hours before closest approach on August, 27, 2016. Image via NASA/JPL-Caltech/SwRI/MSSS

Listen to Jupiter’s auroras

Plus more cool stuff from the Juno spacecraft’s August 27 closest-yet flyby of Jupiter.

The strange mountain on dwarf planet Ceres, called Ahuna Mons.

Update on Dawn mission to Ceres

The Dawn spacecraft is still orbiting Ceres. It went into an extended mission mode on July 1. Some mission highlights and current thinking, here.