The Solar System (Planetary Debris)

1. The Solar System (Planetary Debris) Charles Modequillo Aiko Olaer

2. Planetary Debris • During the formation of the Solar System not everything became the planets and the moons. There are other remnants from the solar nebula that are called planetary debris. These are what we know as asteroids, meteoroids and comets.

4. ASTEROIDS

5. Asteroids • planetary debris made up of chunks of rocks and metals that orbit around the Sun. They are also called planetoids • planetary debris made up of chunks of rocks and metals that orbit around the Sun. They are also called planetoids • compose only a fraction of the Solar System

7. Types of Asteroids • C – Type • S- Type • M - Type

8. C- Type • Carbonaceous (largely carbon, dark) • Consist 75% of the asteroids • Outer orbits

9. S- Type • Silicate (largely silicon, light) • Consist 15% of the asteroids • Inner orbits

10. M- Type • Nickel-iron • Consists about 10% of the asteroids

11. Examples of Known Asteroids • Ceres • Gaspra • Ida

12. Ceres • Largest asteroid • 940 km diameter • 1/10,000 of the mass of Earth’s moon

13. Gaspra • S-Type asteroid • Maximum diameter of 20 km • About 200 million years old

14. Ida • S-Type asteroid • Maximum diameter of 60 km • About 1 billion years old

15. COMETS

16. Comets • Comets are icy matters that follow elliptical orbits around the solar system. As they approach the Sun, comets heat up, emit radiation and also develop a tail.

18. Parts of a Comet

19. Nucleus • Solid portion of the comet • 1 to 10 km in diameter • Density of 100 kg/m3

20. Coma • Evaporated gas and dust forming a halo around the nucleus as the comet approaches the Sun

21. Hydrogen Envelope • Hydrogen gas that surrounds the coma of the comet and trails along for millions of miles

22. Dust Tail • Up to 10 million km long composed of smoke-sized dust particles driven off the nucleus by escaping gases • Broad, diffuse, curved, less deflected by solar wind

23. Ion Tail • Straight out, blown by solar wind • Several hundred million km long composed of plasma and laced with rays and streamers caused by interactions with the solar wind

24. ORBITS

25. Orbits • Having a highly elliptical orbit means that there is point for each comet where it is closest to the Sun. At this point we call that a comet is at its perihelion. There is also a point where the comet is farthest from the sun, this point is called aphelion.

26. Orbits • A period is the time taken by a comet to travel once around the Sun in its orbit. Comets are often classified according to their orbital periods.

27. Period of Orbits • Short-period Orbits • Long Period Comets

28. Short Period Orbits • From Kuiper Belt • Have orbital periods of less than 200 years • 30 to 50 AU (Astronomical Unit) in diameter

29. Long Period Orbits • From Oort Cloud • Orbits up to 100,000 AU in diameter • Periods ranging from 200 years to thousands or even millions of years • Surrounds Sun in all directions

30. Kuiper Belt and Oort Cloud

31. Halley’s Comet • First predicted by Edmund Halley to reappear in 1758 • last visible from Earth in the year 1986 • has been orbiting the Sun since 240 BC

32. Halle-Bopp • Discovered in July 1995 • Was visible to the naked eye in • Perihelion on April 1, 1997 • Period of about 4000 years

33. METEOROIDS

34. Meteoroids • are small bits of rock or metal or ice that are chipped off asteroids or comets. They are debris floating in space outside the Earth’s atmosphere. On the other hand, meteors are meteoroids on the process of entering the Earth’s atmosphere. They are also known as shooting stars.

35. Meteorites • are pieces of a meteoroid that successfully lands on Earth. These meteoroids are the ones responsible for cratering the inner solar system.

37. Types of Meteorites • Iron • Stony Iron • Chondite • Carbonaceous Chondrite • Achondrite

38. Iron • primarily iron and nickel similar to type M asteroids

39. Stony Iron • mixture of iron and stony material like S type asteroids

40. Chondite • similar in composition to the mantles and crusts of the terrestrial planets

41. Carbonaceous Chondite • very similar in composition to the Sun less volatiles, similar to type C asteroid

42. Achondrite • similar to terrestrial basalts, the meteorites believed to have originated on the Moon and Mars are achondrites

43. A very large number of meteoroids enter the Earth's atmosphere each day. The largest found meteorite (Hoba, in Namibia) weighs 60 tons.

45. The average meteoroid enters the atmosphere at between 10 and 70 km/sec. But all but the very largest are quickly decelerated to a few hundred km/hour by atmospheric friction and hit the Earth's surface with very little fanfare. However meteoroids larger than a few hundred tons are slowed very little; only these large (and fortunately rare) ones make craters.

46. Barringer Crater • A crater near Winslow, Arizona • Was formed around 50,000 year ago • Formed by a 30-50 meter diameter iron meteor. • Crater is 1200 meters in diameter, 200 meters deep

48. Meteor Showers in the Philippines

49. Geminids • The Geminids meteor shower is an annual event. Its recent peak was observed in the Philippines last December 14thof 2011. They appear to radiate from the constellation Gemini.