Phenomenon
Einstein Ring
A perfect ring of lensed light.
Formed when a background source, a foreground lens, and the observer align nearly exactly, producing a ring-shaped distorted image.
Overview
Formed when a background source, a foreground lens, and the observer align nearly exactly, producing a ring-shaped distorted image.
See also
Bolide
A fireball that explodes in flight.
Optical Transient
Any short-lived brightening in visible light.
Solar Eclipse
When the Moon stands between Earth and Sun.
Lunar Eclipse
When Earth's shadow falls on the Moon.
Meteor Showers
Cosmic dust burning in our atmosphere.
Aurora (Northern/Southern Lights)
Solar wind painting the upper atmosphere.