Astronomy Picture of the Day: A new photo each day and great archives!
Aurora Activity Monitoring:
Build a Solar System: Enter a size for the sun - one that you can easily imagine, an inch or a foot - and the site will generate the resulting relative distances to the planets. The numbers are eye-opening.
Celestial Calendars: Chart your course thru the cosmos with a beautiful poster & booklet.
Comets and Meteor Showers: A clean and comprehensive site.
Dangerous Asteroids! Harvard's list of potentially dangerous asteroids.
Earth & Sky: Skywatching center.
Equinoxes & Solstices 1992 - 2020:
Extrasolar Planets: California and Carnegie planet search.
Extrasolar Visions: Guide to extrasolar planets.
The Face on Mars:
Falling Into A Black Hole: Animation of the process.
Griffith Observatory:
Hubble Site: All about the Hubble telescope by the Space Telescope Institute.
International Meteor Organization:
Jillian's Guide to Black Holes:
The Lunar Embassy:
Meta Research: Dr Tom Van Flandern's astronomical research site.
Nassim Haramein: The Holofractographic Universe unified field theory. Site has wild flash opening!
Near Earth Asteroid Tracking Home Page:
Official String Theory Website: Cutting edge physics of the next millenium.
The Orion Constellation: Star Alignment Over The Land Of Osiris.
Pegasus Products: Makers of Star Essences.
The Planet Project: Find stars that have planets.
Planetary Conjunctions: A QuickTime Movie of the planets' motions.
PointMe.To/Space: Resources & information on space & astronomy.
Red Planet: Very cool graphics of Mars.
Science @ NASA: The latest news from NASA.
Shadow & Substance: Fun astronomy site with lots of animations.
Small Comets: Every few seconds a snowball the size of a small house breaks up as it enters Earth's atmosphere.....
Solar & Lunar Eclipses: Lists & Maps!
Space Weather News: Science news & info about the Sun-Earth environment. Visit the amazing Aurora Gallery!
Sunrise - Moonrise Tables: Calculate from anywhere in the world!
Universe Today: News on space exploration from around the world.
Virtual Atlas of the Moon: Free software Atlas of the Moon unfortunately only available in Windows format.
Virtual Trips to Black Holes & Neutron Stars:
Yuichi Takasaka: AWESOME, stunning, otherworldly photos of Aurora Borealis in Canada. Don't miss this!

Albert Einstein Online: Many Einstein links here!
Einstein Archives Online: Huge Einstein database.
Extreme Science: Lots of interesting science facts in a huge site!
Famous Curves Java Applet: Site at the University of St Andrews in Scotland where you encounter mathematical java scripting that enables you to experience all the famous curves interactively.
Grand Unification and Time: The Speed of Light Definition of Time. The Grand Unification Theory, Earthquake Watches & Warnings
Math World: Huge mathematics resource.
Molecular Expressions: Extraordinatory website which explores the world of optical microscopy. Myriad galleries full of amazing photos include: birthstones, amino acids, DNA, soft drinks, trees, antibiotics, butterfly wings, dinosaur bones, cocktails, meteorites, flavors, liquid crystals, pharmaceuticals, ice cream etc. etc. You can easily spend days here!
Mystery of the Calender: Site of the Russian Vladimir Pakhomov.
Official U.S. Time: National Institute of Standards & Technology's Time & Frequency Div.
Resonance Project: Scientists guided by the interconnectivity of all things.
Super Natural Minds.com: Site of the Great Minds that changed our world.