Philosophy: What exactly is a black hole?

more »
What is a black hole? A philosopher shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
via Science Daily
Zazzle Space Exploration market place

Spacecraft measurements reveal mechanism of solar wind heating

more »
A new study describes the first direct measurement of how energy is transferred from the chaotic electromagnetic fields in space to the particles that make up the solar wind, leading to the heating of interplanetary space.
via Science Daily
Zazzle Space Exploration market place