Other Solar System Bodies next right hand side Key Point (8-4.1): Summarize the characteristics and movements of objects in the solar system.

Moons Studied with planet they orbit (Not all planets have moons.) movement is based on their revolution around their planet. rocky bodies covered with craters, some have unique characteristics (like atmospheres or volcanoes). How are Moons Studied? How do they move? What do they look like?

Asteroids Irregularly shaped, rocky bodies They vary in size and shape In a region in the solar system known as the “Asteroid Belt” between Mars and Jupiter. They revolve around the Sun. – at different speeds each on it’s own individualized orbits. Some cross paths and can collide. Some even cross Earth’s orbit! – Scientists monitor their positions. What is an asteroid? Where are they located? How do they move?

Asteroids can be as small as 7 feet and as big as 583 miles. The first asteroid was discovered in 1801 by Italian astronomer Giuseppe Piazzi. Named Ceres, it features a diameter of around 950 kilometres and is now regarded as a dwarf planet. Ceres was given dwarf planet status in 2006, along with Pluto, Eris, Makemake and Haumeadwarf planetPluto Asteroids are small Solar System bodies that orbit the Sun. Made of rock and metal, they can also contain organic compounds (some scientists suggest that asteroids could have brought they necessary chemicals to start life on Earth).Sun

Comets small icy and rocky objects left over from the formation of the solar system and the oort cloud. Have unique, long, narrow elliptical orbits. Most orbit the Sun at a very great distance, but sometimes they have a short orbit and come close to Earth where we can see them. – Halley’s Comet (every 75 years) What are comets made of? What do they look like? How do they move?

Parts of a Comet Main body / head / nucleus = made of dust and ices of water, methane and ammonia Coma = bright light surrounding the nucleus Tail = debris pushed off the head as the comet nears the Sun. Always points away from the Sun and gets larger as it nears the Sun.

The name comet comes from the Greek word meaning ‘hair of the head’, it came from the Greek philosopher Aristotle who observed comets as ‘stars with hair’Aristotle In July 1994, the Shoemaker-Levy 9 comet broke apart and collided with Jupiter. This event gave astronomers a unique opportunity to observe what happens when such a collision occurs.Jupiter The largest fragments were 2 km (1.2 mi) in diameter and struck Jupiter at a speed of around 60 km/s (37 mi/s). The impact scars were clearly visible for months after the impact. Halley is the only known short-period comet that is clearly visible to the naked eye from Earth, and the only naked-eye comet that might appear twice in a human lifetime. Halley last appeared in the inner Solar System in 1986 and will next appear in mid-2061.

Meteoroids chunks of rock that randomly move around the solar system. (no fixed orbit) Location and movement result in different terms: – Meteor = when the chunk of rock burns up in a planet’s atmosphere (shooting star) – Meteorite = when the chunk of rock strikes the surface of a planet or moon What are Meteoroids? How are Meteoroids broken down? What is a shooting star? What is it called when it hits Earth?