ASTRONOMY (Celestial Navigation)

• Real-Time Satellite Images of Day and Night
• Time, Sun, and the Stars
• Star Maps (Interactive)
• Look up Meanings of Astronomy Terms
• Free Star Maps To Print Out
• Current Solar Zenith Angles

HOW DO OCEANS WORK?

• Primer on Ocean Currents
• The Basics of Tides (College)
• Catalan Tide Chart (1391)Verrry Slow
• The Ocean Atlas of Hawai'i
• Indian Ocean Area Map
• Studying the Ocean from Outer Space

HELP! I Took History So I Wouldn't Have to Remember Trigonometry

• MacTutor History of Mathematics archive
• The Trigonometric Functions

WEATHER

• Basic Questions About Meterology Answered
• How to Read a Weather Map
• What Is the Weather On the Ocean Right Now?
• Intro to El Niño
• El Niño Today
• What About El Niño?
• El Niño 's History
• Meanwhile The Weather in the South Pacific Is . . .
• Weather Movies--They Take Time to Download--But Worth It!
• Weather Vocabulary

Primitive Navigation

• Finding Your Way with a Map and a Compass
• Dead Reckoning
• Finding Your Way to Navigation on the Net

Navigation with GPS
Global Positioning System

• A Global Positioning System Library On-Line
• Introduction to Global Positioning
• Great Circle Path Display
• US Coast Guard's Guide for GPS Users

Calendars

• Basics of Calendars
• Lunar to Solar Calendar Conversions
• Basics of the Muslim Calendar
• Hebrew Calendars Explained
• Calendar Zone

Earth's Magnetism

• Global Magnetic Fields
• Local Magnetic Fields
• How magnetic variation affects your course at sea
• The Most Complete Information on Magnetic Variation on the Web

Cartography

• Why Are There No Perfect Maps?
• Answer: Girard's Theorem
• Best Guide to Geographic Materials
• Fundamentals of Cartography
• Working with Maps: The Basics
• Maps From Everwhere, Maps for Everything
• Have Coordinates, Need Map
• Zoom in on the World (From Xerox)
• Map Resources
• Lots of Pretty Map Pictures

Best Historical Maps On-Line

• Best Virtual Map Room
• Huntington Library
• Ptolemy's "Star Maps"
• Martin Behaim's Globe In German
• Late Medieval Maps