Celestial Objects in Space Lesson 4a Celestial Objects in Space

Comet Shoemaker-Levy 9 hit Jupiter in 1994. chunks of frozen gases, rock & dust that orbit the sun tail is formed when the comet comes close to the Sun Comet Tails – the white tail is sunlight reflecting off the particles that have been released; the blue tail is made of gases (ion or gas tail) Comet Shoemaker-Levy 9 hit Jupiter in 1994.

Asteroids Irregular shaped rocky objects many orbit around the Sun and this is called an asteroid belt Left over from the formation of the solar system

Meteors & Meteorites A meteoroid is a clump of rock or metal which is pulled towards Earth by gravity In Earth’s atmosphere it heats up, begins to glow and becomes a meteor If the object is not vaporized before it contacts the Earth’s surface it is called a meteorite meteoroid meteor meteor shower

What’s the difference? Asteroid: Small; inactive made of rock, carbon or metal - Orbits the sun Comet: small; sometimes active object made of dirt, gas and ice Meteoroid: small particle from an asteroid or comet orbits the sun Meteor: - A meteoroid that burns up in the Earth's atmosphere - a shooting star. Meteorite: - A meteoroid that survives its passage through the Earth's atmosphere and impacts the Earth's surface.

Moons/Satellites Large natural objects which revolve around a planet many planets have more than one moon Earth’s moon has no atmosphere and has hills/valleys/craters after the invention of the telescope Galileo saw 4 moons of Jupiter Moons can come in a variety of size and with a variety of surfaces

Stars A STAR is a luminous ball of plasma that is held together by gravity. What is the nearest star to Earth? What is the nearest star to the Sun?

Binary Solar System

Stars Polaris pole star for the Northern Hemisphere 390 light years from Earth part of a binary star system Sirius the brightest star in the sky (70 times more luminous than the sun) 8.6 light years from the Earth Betelgeuse one of the brightest stars in the sky supergiant 1,000 times bigger than the Sun but cooler than the Sun

Outside our Solar System Voyager I, Pioneer 10 & 11 and Voyager 2 built to explore outside our solar system Took 20 years to leave solar system will reach the nearest star in 50 000 years

video Bill Nye- Comets and Meteors