1. Earth in danger Understanding the risks for human life Juraj Vančo 93. prístav vodných skautov a skautiek Tortuga Trenčín Sep 2013

2. Agenda Voting Comets and meteors Observation Expedition for Meteors Kykula 2013 Known meteors in the recent history Solar wind Impacts (physics)

3. Comets and meteors Comet: an object flying in the universe – Known track, ellipsoidal (Kepler’s law) – Solar system: Sun is the mass point – Usually cannot be observed by naked-eye – Known shuffles: Halley, Hale Bopp, Hyakutake Meteor: an object released from shuffle – Track roughly copies mother’s shuffle track – Predictable – Small size – Can be observed by naked-eye

4. Observation Expedition for Meteors Kykula 2013 Perseids Mother shuffle: Swift- Tuffle – Circuit period: 120 years – Last traversal: 25 years ago – Date: around 10 th of August (Vavrinec) Expedition Conditions: – Moon in last quarter – No clouds – After rain

5. Observation Expedition for Meteors Kykula 2013 Central point: Perseus – Where is Perseus? – What does it mean? Typical properties: fast, long Another method of observation: radio waves – How does it work?

6. Known meteors

7. “meteorit”: meteor fallen on the Earth’s surface Explosions: one or more – Explosion severity: atom bomb has less power Past 100 years meteors (http://bolid.es) – Tunguska (Siberia) in 1914 – Čeljabinsk (Siberia) in 2013 – Košice (Slovakia) in 2011

8. Known meteors Observed: column of bluish light as bright as the Sun 10 – 15 Mtons of TNT ~ 1000 x Hiroshima bomb

9. Known meteors “meteorit”: meteor fallen on the Earth’s surface Explosions: one or more – Explosion severity: atom bomb has less power Past 100 years meteors (http://bolid.es) – Tunguska (Siberia) in 1914 – Čeljabinsk (Siberia) in 2013 – Košice (Slovakia) in 2011

10. Known meteors 440 ktons of TNT ~ 20 – 30 x Hiroshima bomb

11. Known meteors “meteorit”: meteor fallen on the Earth’s surface Explosions: one or more – Explosion severity: atom bomb has less power Past 100 years meteors (http://bolid.es) – Tunguska (Siberia) in 1914 – Čeljabinsk (Siberia) in 2013 – Košice (Slovakia) in 2011

12. Solar wind Ionised mass particles released from the Sun’s gravitation – Sun’s activity period The Sun: eruptions Effects for the Earth – The most vulnerable systems: satellites, electronics

13. Solar wind Ionised mass particles released from the Sun’s gravitation – Sun’s activity period The Sun: eruptions Effects for the Earth – The most vulnerable systems: satellites, electronics

14. Solar wind impacts Effects for the Earth – 1972: telecom AT&T, USA – 1989: electricity blackout, Canada – 2000: satellites destroyed (short circuit) – 2006: GPS blackout, satellites

15. NASA new mission: asteroids So, when? Voting? Thanks for watching Q & A