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Incredible color-changing! How does octopus do it?

Here’s a different kind of color explosion for the holiday. How and why the octopus, squid, and cuttlefish change colors.

Black hole wakes up after 27 years

On June 15, a monster black hole in the binary system V404 Cygni started showing signs of extraordinary activity that hasn’t happened since 1989. Astronomers around the world are watching the event.

SpaceX rocket explodes after launch

An unmanned SpaceX Falcon 9 rocket, carrying a Dragon spacecraft loaded with supplies for the International Space Station (ISS), exploded Sunday (June 28, 2015) shortly after liftoff from Cape Canaveral in Florida. The astronauts aboard ISS have about four months of supplies left, but the failure has dealt a blow to NASA, which has had three failed shipments of cargo to ISS in the past eight months.

Can a human singing voice shatter glass?

If you run a damp finger along the rim of a glass, you might hear a faint, ghostly hum – the resonant frequency of the glass. To shatter the glass, a singer’s voice has to match that frequency, or pitch, at an extremely loud level, and the glass must have microscopic defects.

Video: Brainy octopus and its coconut

We can’t get enough of the coolness of octopuses here at Earthsky. Watch what this octopus does with coconut shells.

Sixth mass extinction is happening now

We are entering a mass extinction that threatens humanity’s existence, says a new study. Earth’s species are disappearing faster than at any time since the dinosaurs’ demise, some 15 to 100 times faster than the normal rate between past mass extinctions.

All systems go for Europa mission

NASA scientists are turning more and more to the search for life on other worlds. In our solar system, a promising place to look for life is Jupiter’s moon Europa, which might have a liquid water ocean beneath its icy crust. Late last week, scientists announced that a new mission to Europa – proposed to launch in the 2020s – is moving forward from concept review to development.

Watching solstices and equinoxes from space

How sunlight falls on Earth’s surface during the solstices and equinoxes, as seen from geosynchronous orbit.

A robotic dog’s mortality

When Sony stopped manufacturing replacement parts for its Aibo pet robot, owners scrambled to save the robot-dogs that had become part of their families.

New Horizons has a cool teaser trailer!

New video captures the excitement of the upcoming July 14 spacecraft encounter with Pluto. The real thing will be better and is just ahead!