Program 1 Solar Systems

After viewing the video and participating in one or more of the Hands-On Activities, students will be able to:
• identify and describe the main objects found in our solar system (terrestrial and gas giant planets, moons, comets and asteroids)
• model the relative sizes of the planets and demonstrate the scale of the solar system
• describe the principal forces which shape our solar system, e.g. gravity and nuclear fusion
• situate our solar system in the Universe, referring to age, distance and the numbers of other stars and galaxies

Program Description
Recent images of the planets, moons and small bodies of our solar system introduce students to the places and processes that will be explored throughout the video series. This program has three sections:
• "A Family Portrait" (5:06) uses the last picture taken by the Voyager 1 spacecraft before it left our solar system to introduce the 2 main categories of planets-terrestrial and gas giants-as well as the other objects in our solar system (the icy planet, Pluto, asteroids and comets).
• "Birth and Evolution of the Solar System" (3:32) explores the broader perspective of time and space within which our solar system was born and evolved (some 4.5 billion years), and from the Big Bang to the present, a period of about 15 billion years. It provides current estimates of the number of stars in our galaxy (about 100 billion) and galaxies in the Universe (again, about 100 billion).
• "Other Worlds" (2:00) presents recent findings of other solar systems, till now relatively large and presumably gas giant planets around other stars, detected by the wobbles their gravity creates in the light of their parent stars.

Science-Mentors explain key concepts. Comet researcher Claudia Alexander from JPL explains comparative planetology and why studying other planets helps us understand Earth in new ways. Mars mission designer Wayne Lee (also from JPL) describes 2 key forces shaping our solar system-gravity and nuclear fusion in our star, the Sun. Gravity makes a solar system, and astronomers use the effects of gravity to reveal distant solar systems otherwise invisible. U.C. Berkeley astronomer Geoff Marcy discusses modern techniques that can detect a giant star's tiny wobbles from thousands of light years away. Chris Chyba, an expert on the search for life in the Universe and a continuing presence in this series, explains why he expects more and more solar systems to be discovered. (Please use the PTSOLAR website to track new discoveries which will mean that more and more planets, and very likely much smaller and more Earth-like planets, will be discovered in coming years.)