Understanding the world through science -- The science behind time, tides, and revolutions -- Why did people once think the Earth was flat? -- How did we work out that the Earth revolved around the sun? -- How long does it take for the Earth to orbit the sun? -- What causes the seasons to change? -- Why are there 12 months in a year? -- Why are there 24 hours in a day? -- How was time measured before there were clocks? -- How accurate is the most accurate clock on Earth? -- What is the international date line? -- Why do some places use daylight saving time? -- Why don't we fall off the face of the Earth? -- What causes tides? -- What is the difference between a solar eclipse and a lunar eclipse?
This resource is supported by the Institute of Museum and Library Services under the provisions of the Library Services and Technology Act as administered by State Library of Iowa.