The satellite with X-ray vision

In the early hours of October 23, 2011, ROSAT was engulfed in the waves of the Indian Ocean. This was the end of a success story that is unparalleled in German space exploration research. The satellite, developed and built ...

How NASA prepares spacecraft for the harsh radiation of space

In a small, square room walled by four feet of concrete, the air smells as if a lightning storm just passed through—crisp and acrid, like cleaning supplies. Outside, that's the smell of lightning ripping apart oxygen in ...

Image: Partial Gravity Simulator practice

In preparation for his Beyond mission, ESA astronaut Luca Parmitano was at the Johnson Space Center in Houston, USA, in March 2019. Here he is strapped to the Partial Gravity Simulator to practice repairing the dark-matter ...

The space we travel through

When sea-faring nations began to explore new regions of the world, one of their biggest concerns in making the journey safely was how to cope with weather. They could harness the wind for power. They could rely on the Sun ...

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Cosmic ray

Cosmic rays are energetic particles originating from outer space that impinge on Earth's atmosphere. Almost 90% of all the incoming cosmic ray particles are protons, almost 10% are helium nuclei (alpha particles), and slightly under 1% are heavier elements and electrons (beta minus particles). The term ray is a misnomer, as cosmic particles arrive individually, not in the form of a ray or beam of particles.

The variety of particle energies reflects the wide variety of sources. The origins of these particles range from energetic processes on the Sun all the way to as yet unknown events in the farthest reaches of the visible universe. Cosmic rays can have energies of over 1020 eV, far higher than the 1012 to 1013 eV that man-made particle accelerators can produce. (See Ultra-high-energy cosmic rays for a description of the detection of a single particle with an energy of about 50 J, the same as a well-hit tennis ball at 42 m/s [about 94 mph].) There has been interest in investigating cosmic rays of even greater energies.

This text uses material from Wikipedia, licensed under CC BY-SA