Not Your Parents’ Solar System! Original ideas from Frank Summers Space Telescope Science Institute NSTA Institute Symposium November 15, 2003

Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto My Very Energetic Mother Just Served Us Nine Pizzas

Our Solar System Sun Nine planets But there is more!

21 st Century View Six families of the solar system – Star – Our sun – Inner planets - Rocky planets Mercury Venus Earth Mars – Asteroid belt – Outer planets - Gas giant planets Jupiter Saturn Uranus Neptune – Kuiper belt – Oort cloud

Location of asteroid belt

What about Pluto? It’s not a rocky planet It’s not a gas giant planet

Pluto is so far away, even early photos from the Hubble Space Telescope couldn’t make out the details of the dwarf planet The images revealed an icy, mottled, dark molasses-colored world with a surprising amount of activity. Comparing Hubble images taken in 1994 vs. 2003, researchers saw that Pluto's northern hemisphere brightened while the southern hemisphere dimmed. Observations suggested that Pluto's atmosphere doubled in mass during approximately the same time period. These results show that Pluto is not just a frozen ball of rock and ice, but a lively world with much to study. The Hubble images, fuzzy though they may be, helped to plan the flyby of Pluto by the New Horizons probe in 2015.

Pluto has a moon! First Pictures of Pluto/Charon 1995 – Hubble Space Telescope infrared 1996 – Hubble Space Telescope visible

NEWS FLASH! Pluto has FIVE moons! Charon Hydra Nix Styx Kerberos Does that make it a planet because it has moons?

Pluto’s orbit

New Horizons on the way to Pluto In 2006, NASA dispatched an ambassador to the planetary frontier: The New Horizons spacecraft, now more than halfway between Earth and Pluto, is on approach for a dramatic flight past the icy dwarf planet and its moons in July After 10 years and more than 3 billion miles, on a historic voyage that has already taken it over the storms and around the moons of Jupiter, New Horizons will shed light on new kinds of worlds on the outskirts of the solar system. Pluto gets closer by the day, and New Horizons continues into rare territory, as just the fifth probe to traverse interplanetary space so far from the sun. And the first ever to travel to Pluto.

New Horizons

What else is in our solar system? The Kuiper Belt The Kuiper Belt is a disc-shaped region of icy objects beyond the orbit of Neptune -- billions of kilometers from our sun. Pluto and Eris are the best known of these icy worlds. There may be hundreds more of these ice dwarfs out there. The Kuiper Belt and even more distant Oort Cloud are believed to be the home of comets that orbit our sun.

Eris larger than Pluto Who Knew?

Compare Eris’ orbit to Pluto’s

Even more out there: Oort Cloud lots of icy, comets orbiting our Sun

So… is Pluto a planet? Or not? What is a Planet? NASA multimedia Our World Pluto, NASA video What is a Planet? NASA multimedia Our World Pluto, NASA video

Writing Paragraph Classify Pluto as a planet, dwarf planet, or Kuiper belt object. -Support your answer with facts about Pluto, the other planet and objects, and your knowledge of our solar system.