2003 UB313: The 10th Planet?

1. 2003 UB313: The 10th Planet?

2. Quiz 4, AU13, A161 – Grades B C D A E Curve: 4%

3. Extra-Solar or Exoplanets • Planets around stars other than the Sun • Difficult to observe • Hundreds discovered (> 2000 so far) • Jupiter to Earth sizes • Surprise: Some stars with Jupiter mass planets within 1 AU (revised theory of planet formation ?) • Habitable Zone: Distance out to where water is liquid

4. Extra-solar planets around distant stars

5. First image of an exoplanet

6. Transiting Hot Saturn with a large dense core Astronomers have found a weird new creature: a planet whose core holds 65 Earths' worth of heavy rocky stuff.

7. Saturn-mass planet transiting across its star

8. Discovering Planets with Life Sunlight is reflected off the Earth, hits the Moon and bounces back to Earth Earthshine is seen in the faint glow our world gives to dark areas of the Moon The light carries information about Earth's atmosphere and surface properties Scientists see details in the light that betray different gases, even vegetation The knowledge can be applied to the search for distant worlds Detect the presence of atoms/molecules that make up vegetation or life

9. 7.5 Earth-mass planet

10. Found: 3 'Neptunes' and a 'hot Jupiter' 600 LY’s from the Earth, the planetary system is in the habitable zone with conditions enabling liquid water to exist

11. HD 188753 b - A planet in a triple star system

12. 5.9 Earth mass planet in Gliese 876 system

13. Techniques for discovering exoplanets • Direct observation  few • Protoplanetary disks  Many seen • Transit across the star  Most (Doppler shifts) • Gravitational Microlensing  ~10 • Spectroscopic observation  First indications from absorption line wavelengths • Over 2000 found • KEPLER spacecraft  over 1000+ • “Free-floating” planets, unattached to stars