This issue of The Earth & I examines communities interconnected through solar grids (see Energy Section). Far beyond these communities lies another “solar community” with star-power like no other: the Universe.
The European Space Agency (ESA) launched the satellite Hipparcos in 1989 to accurately measure the positions (and motions) of nearly 120,000 stars. It can also approximate the positions of about a million other stars with less precision.
Besides our Sun, there are ten other stars in our neighborhood.
The nearest star to our own is 39,900,000,000,000 km (4.22 light years) away. Scientists have named it Proxima Centauri.
The farthest away, named Eta Cassiopeiae, is 19 light years away. At Voyager 1’s speed of 17.3 km/s, it would take some 330,700 years to arrive there.
The red dwarf star Gliese 581 is about 20 light years from Earth. Its third planet appears to be an example of a possible terrestrial extrasolar planet where conditions are favorable (not too hot or cold) for life as it is on Earth.