Our Solar System & Exoplanets (Power Point 08) Image Credit: Slyavula Education Image Credit: NASA

Student Learning Objectives Construct a model of the Solar System Identify and locate objects in our solar system Describe planet formation processes Explain how other “solar” systems (exoplanets) are found

Source: Solar System Videos

What are the main characteristics of our solar system? All of the objects in our solar system formed at about the same time.   4.5 Billion Years Ago Most objects in our solar system revolve and rotate counterclockwise as viewed from above the northern hemisphere. Venus rotates backwards Uranus rotates on its side

Our Solar System Our solar system has one star, the Sun. Planets orbit the Sun. Moons orbit the planets. Dwarf planets orbit the Sun. Asteroids and Comets orbit the Sun.

Practice How many stars are within our solar system? How many moons do you think are in our solar system? What are the names of the planets, in order, from the Sun outward? How many other stars in our galaxy have planets?

What is the process of planet formation? Planets form in a disk of rotating gas and dust at the same time the as the star is forming. Solar Nebula Theory Condensation Accretion Planetesimals Proto-planets Planets

http://www.spacetelescope.org/images/opo9545c/

The Protoplanetary Disk of HL Tauri Image Credit: ALMA (ESO/NAOJ/NRAO), NSF Image Credit: APOD 2014 - ALMA (ESO/NAOJ/NRAO), NSF

2 Zones There are two general zones of condensing materials in the protoplanetary disk. Near & Far from Sun Metals Iron & Silicates Far from Sun Ices Water, Methane, Ammonia

Image Credit: NASA

Practice What is the cause of the 2 condensation zones? Iron has a vaporization temperature of 2870 ºC. Would you expect iron to condense near or far from a star? Methane boils at −161 ºC. In which “zone” will methane condense?

The Solar Nebula Theory https://www.youtube.com/watch?v=fbq-NfLFLgk from Youtube

Continuing System Formation Migration Differentiation Atmosphere Clearing of the Nebula Bombardment Image Credit: NASA

Differentiation Artist rendition of the formation of rocky bodies in the solar system – how they form and differentiate and evolve into terrestrial planets. Image credit: NASA/JPL-Caltech

Atmosphere & Leftovers Atmospheres form on some solid planets. Outgassing/Volcanism Comet Impacts Large planets capture atmosphere before the nebula is cleared. Leftover planetesimals become moons, asteroids, & comets, and have collisions (bombardment). Phobos Image Credit: NASA

Practice Explain why the motion of objects in our solar system is relatively uniform. What factors would determine whether a planet is able to maintain an atmosphere? Earth has an abundance of oxygen. Where does earth get its abundance of oxygen?

How do astronomers search for other “solar” systems? Gravity Eclipses (Light Curves) Microlensing Direct Imaging Image Credit: NASA

Gravitational Wobble Gravity causes a star to wobble. The wobble may result in a Doppler shift. The wobble may result in astrometric shifts in star position. Video by ESO

Eclipses When a planet crosses in front of a star (transits), there is a decrease in brightness from the star. Image Credit: NASA http://kepler.nasa.gov/Mission/discoveries/

Microlensing Light follows the curvature of space. May result in more images on one side than the other May cause increased brightness as both the planet and the star bend the light to the observer Image Credit: NASA

Microlensing & Brightness https://www.youtube.com/watch?v=e0EFoYwtrFM Source: Hubble Space Telescope

Direct Imaging Image Credit: JPL/NASA

Direct Image of Beta Pictoris b Beta Pictoris b is a giant planet – several times larger than Jupiter – and is approximately ten million years old. (January 2014) Image Credit: Gemini Planet Imager

Practice Is it possible to view the surface features of an exoplanet? Have astronomers searched a relatively large or small portion of space for exoplanets? What is the primary method used by astronomers for finding exoplanets?

What is the Habitable Zone? The habitable zone is where liquid water is possible. Image Credit: NASA Kepler Mission

Practice Where is our Earth? Where is Venus? Where is Mars? Image Credit: NASA

The Kepler 11 System Image Credit: NASA

Kepler 16 NASA's Kepler Mission discovers a world orbiting 2 Stars (September 2011) Image Credit: NASA

Image Credit: NASA

First Earth-Size Planet in Habitable Zone (April 2014) Image Credit: NASA

Practice Astronomers are searching for planets around stars like our Sun. Why? Particular importance is placed on finding Earth size planets. Why? Compare and contrast the habitable zone of a red star to the habitable zone for our Sun.