Stargazing Basics

How to Make a Sundial the Simple Way

Sundials are amazingly simple yet effective devices. They range from sticks planted in the ground to precision-machined marvels costing thousands of dollars. The design shown here can be constructed in minutes from materials lying around your house, but it's surprisingly accurate.

Porcelain sun dial

Hobby-based Q&A

Can you use a replica of an 18th century New England sundial in Washington?

I have a museum’s pewter replica of an 18th-century New England sundial. The inscription says it was designed for latitude 42°. Can I use this sundial in Seattle, Washington? The iconic garden sundial, with triangular shadow-casting gnomon and horizontal plate, gives accurate readings at the latitude for which its hour…

Hobby-based Q&A

How many daylight hours do you get in a year?

No matter where in the world you live, do you get the same number of daylight hours over the course of a year? No. The equator actually gets fewer hours of daylight than most other latitudes. Any given place would be in daylight exactly 50 percent of a year’s time…

Hobby-based Q&A

When is the earliest sunrise of the year?

The earliest sunrise of the year doesn't always occur on June 20th (the solstice), which has the longest day. Why? The earliest sunrise actually depends partly on latitude. In 2004, for latitude 40° north, it was June 13th. For 50° north, the earliest sunrise was on June 16th. At 30°…