[00:09] Today we are accustomed to seeing the Earth as an object suspended in space. But before the dawn of the space age, few people could imagine that they lived on a planet surrounded by the hostile environment of space.

[00:20] From space it's easy to see Earth as a single living system. No other known planet has the same combination of water, atmosphere and sunlight as Earth. Oceans, clouds and continents are bathed in energy from the sun.

[00:32] Sunlight provides the energy plants use to grow, metabolize and reproduce. Animals eat plants, so they also thrive on solar energy.

[00:40] Solar radiation creates temperature differences that drive winds, a key to oceanic and atmospheric circulation for our weather.

[00:47] From space we see changes in the Earth's systems from gentle rainstorms and forest fires, to volcanic eruptions, even large oil spills.

[00:55] And with the aid of satellites we are beginning to understand how the Earth changes over time and how human activities affect our home planet.

[01:02] The more we change our environment, the more we must adjust to the consequences. The things we do today are left for our children and grandchildren to cope with.

[01:10] And while there may be Earthlike planets orbiting other suns, they're far away, so being good stewards of our island in space makes common sense.

[01:18] For Our Changing Planet, I'm Lou Varricchio, and I'm Jane Joyce. To learn more about Our Changing Planet, visit us on the web at www.umac.org/ocp.