- How to find and observe M31 (TOTS#1) (eyesonthesky.com)
Messier 31 is the closest spiral galaxy to our own Milky Way galaxy. It is over 2 million light years away, so the photons reaching your eye in a telescope tonight left that galaxy some 2+ million years ago, just before the time of homo erectus. The Andromeda galaxy is on a collision course with our own, and the two will merge in about 4 billion years.
- Electricity (Wikipedia)
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell’s equations. Common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others.
