Astronomy for Beginners
Here’s where you’ll find observing guides, how-to articles and great astronomy hints and tips. Don’t forget to also check out our comprehensive astronomy dictionary.
The relic of a supernova explosion, comprising a neutron star, pulsar or black hole, and an expanding cloud of gas.
A vertical column of light that appears above or below the Sun at sunset or -rise.
An optical defect in a lens, which means light rays that enter the edge of the lens at an angle converge so as not to be brought to a sharp focus. The result is a smearing of detail towards the edge of the field of view.