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.
This is the reflection of light usually seen around the gaseous ejections from massive stars or sometimes supernova. Perhaps the most prominent of all recently observed light echoes was the one seen around the exploding star V838 Monocerotis.
The distance from the eyepiece at which you can see the full field of view. People who wear glasses observe further away from the eyepiece and so need a longer eye relief.
The period during a transit or an eclipse when the smaller celestial body begins to cross the disc of the larger object. Egress marks the exit of the transiting or eclipsing body.