1. The Solar System Other Objects

2. Objects We know of the common objects that orbit in our system, planets and moons, but there are more objects out there: comets, meteoroids, and asteroids to name a few.

3. Comets A comet is composed of dust and rock particles mixed with frozen water, CH 4, and NH 3. – You may of heard of Halley’s comet, it was last seen in 1986. – Halley’s comet has been observed for over 2,000 years but English astronomer Edmund Halley was the first to realize that this comet was being sighted every 76 years. The last sighting happening in 1986.

4. Oort Cloud Jan Oort, Dutch astronomer, proposed an idea that a large collection of comets lies in a cloud that completely surrounds the solar system, this cloud is known as the Oort Cloud. Oort Cloud is located beyond the orbit of Pluto. It is thought that gravity of the Sun and nearby stars interact with comets, they can either escape or get caught in smaller orbits.

5. Comet Hale-Bopp July 23, 1995 two amateur astronomers discovered a new comet, Comet Hale-Bopp, was headed toward the Sun. Larger than most comets it was the brightest comets visible from Earth in 20 years.

6. Structure of Comets Hubble Space Telescope and International Cometary Explorer gathered information about the structure of comets, it has found that a comet is like a large, dirty snowball or a mass of frozen ice and rock.

7. The Hubble Space Telescope stands tall in the cargo bay of the space shuttle Atlantis following its capture on Wednesday, May 13, 2009. The STS-125 mission began a series of spacewalks the following day to service Hubble. Over 11 days and five spacewalks, Atlantis' crew will make repairs and upgrades to the telescope, leaving it better than ever and ready for another five years--or more--of research.

8. As the comet approaches the Sun it changes, the ices (H 2 O, CH 4, and NH 3 ) vaporize because of the heat from the Sun. Dust and bits of rock are released. A coma (vaporized gases and released dust form a bright cloud) forms around the nucleus (solid part) of the comet. Solar wind pushes on the gases and released dust in the coma causing the particles to form a tail that always points away from the Sun.

10. Meteoroids, Meteors, and Meteorites When comets vaporize and break up after they have passed the Sun many times, small pieces of the comet’s nucleus spread out into a loose group within the original orbit of the comet, these pieces are called meteoroids.

11. Meteor When a meteoroid crosses the position of Earth and enters Earth’s atmosphere at speeds of 15 km/s to 70 km/s they are so small that they burn up in Earth’s atmosphere. When a meteoroid burns up in our atmosphere it is called a meteor, more often called shooting stars by people. Fireballs and Meteorites - SOTT.NET: August 2011

12. Meteor Showers When Earth passes into the orbit of an old comet, we are able to see many small particles of rock and dust enter the atmosphere, because we are able to see more meteors than usual it is called a meteor shower. Quadrantid meteor shower 2012, seen over the Florida Keys. Image credit/copyright to Jeff Berkes.Jeff Berkes

13. Meteorite When a meteoroid is large enough, it may not burn up completely in our atmosphere. If it strikes the Earth it is a meteorite. Fragments of the Sutter’s Mill meteorite fall collected by NASA Ames and SETI Institute meteor astronomer Dr. Peter Jenniskens in the evening of Tuesday April 24, two days after the fall. This was the second recovered find. Image credit: NASA / Eric James Merv de Haas horse pasture, near Lotus, California, which is the site of where the Sutter’s Mill meteorite fragment was found on May 3, 2012. The site was searched during ground search using aerial sightings.

14. Asteroids An asteroid is piece of rock similar to the material that formed into the planets. Most are located between the orbits of Mars and Jupiter in an area called the asteroid belt.

15. Asteroid Belt You may be asking why the asteroids don’t move from this area between Mars and Jupiter, scientists think that the gravity of Jupiter might have kept a planet from forming in the area where the asteroid belt is located. Asteroids that are not in the belt may have been thrown out of the belt by Jupiter’s gravity. – These asteroids could have turned into other planets moons.

16. This diagram shows a bird's eye view of our asteroid belt, which lies between the orbits of Mars (red) and Jupiter (purple). NASA's Wide-field Infrared Survey Explorer, or WISE, will see hundreds of thousands of asteroids with diameters larger than 3 kilometers (1.9 miles). The green dots represent populations of asteroids - yellow illustrates the populations WISE is expected to see.

17. Exploring Asteroids Sizes of asteroids range from tiny particles to object 940 km in diameter. Ceres is the larges and the first discovered. Next three in size order are Vesta (530 km), Palas (522 km), and 10 Hygiea (430 km).

19. NEAR Near Earth Asteroid Rendezvous – On February 14, 2000 NEAR spacecraft went into orbit around asteroid 433 Eros and began it’s one year mission of data gathering. It showed us that Eros surface has a large number of craters, and might be similar to the most common type of meteorite that strikes Earth. – On February 12, 2001 NEAR ended its mission by becoming the first spacecraft to land softly on an asteroid.

20. An artist's impression of the NEAR spacecraft descending to the surface of asteroid Eros. Credit: NASA