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Find Your Inner Astronomer...
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Astronomy & Telescopes Glossary - L
Limb - The edge of a planet or moon. The upper limb is the first part of it to become visible or the last part to disappear from view.
Limiting magnitude - The magnitude of the dimmest star you can see overhead on a given night.
Local Group - The cluster of 30 galaxies to which we belong. The largest of the galaxies are the Andromeda galaxy, Triangulum, and the Milky Way galaxy.
Local sideral time (LST) - Local Sidereal Time (LST) is measured by the right ascension that is currently at the local observer's meridian. Astronomers use LST to aim telescopes at celestial objects.
Longitude - The angular distance east or west of the Prime Meridian of a celestial object.
Lunar eclipse - An eclipse that occurs when the Earth's shadow falls on the moon.
Lunar month - A lunar month (or synodic month) lasts 29 days, 12 hours and is the time between two successive full moon.
Lunar phases - The phases of the Moon, including new moon, waxing crescent moon, first quarter moon, waxing gibbous moon, full moon, waning gibbous moon, last quarter moon, and waning crescent moon.