What Are Cosmic Rays?
Cosmic rays are atom fragments that rain down on the Earth from outside of the solar system.
Cosmic rays are atom fragments that rain down on the Earth from outside of the solar system.
The Hubble Space Telescope may be turning 26 years old this weekend, but its vision is still out of this world. Case in point: this jaw-dropping view of the Bubble Nebula to celebrate the iconic space observatory's birthday.
Which places in the solar system are the best bets to host alien life? Our friends at ThinkGeek.com recently asked 2,400 readers this very question, and the results are pretty interesting.
The Hubble Space Telescope, launched on 24 April 1990, took four images with its Wide Field Camera 3 to cover the entire expanse of this 10 light year-wide spherical envelop of expanding gas.
Pulsars may look like stars that blink on and off, but these objects are not actually stars and don't actually pulse. So what is a pulsar?
Intergalactic fun with recycled materials: In this 'Curious World' original, a space-inspired kid shows you how to create your own imaginative starship. Fly it wherever you can dream of.
An instrument built to help search for ripples in space-time could also give scientists an estimate of how often spacecraft are peppered with tiny, potentially hazardous space rocks.
Scientists have yet to hear a predicted "hum" of gravitational waves generated by collisions of supermassive black holes throughout the universe. But this lack of detection is interesting, potentially revealing new details about galaxy evolution.
Mice that spent less than two weeks in space back in 2011 — during STS-135, the final mission of NASA's space shuttle program — came back to Earth showing signs of early-stage liver disease, a new study reports.
The smallest full moon of 2016 will light up the night sky this weekend, and you can get a sneak preview of the lunar event in a free webcast from the Slooh community observatory tonight (April 21).
Astronaut Tim Peake, the U.K.'s first crewmember on the International Space Station, celebrated Queen Elizabeth II's 90th birthday by making the ultimate zero-gravity birthday card.
This IMAX and IMAX 3D film 'A Beautiful Planet' is the latest in a long tradition, where astronauts become cinematographers to capture the beauty of our planet from the International Space Station and document the changes they see.
At least two huge, relatively nearby stars exploded within the last few million years, a new study suggests. The finding bolsters the emerging view that supernovas have affected our planet, and perhaps even the evolution of humanity, in the recent past.
Progress spacecraft are automated, unpiloted and single-use vehicles that typically deliver fuel and supplies to the International Space Station.