Presentation on theme: "Astronomy Science vocabulary:"— Presentation transcript:
1 Astronomy Science vocabulary: Comets, meteoroids, asteroids, phases of the moon, eclipses
2 CometsNOften referred to as “Dirty snowballs”, comets are a small body of ice, rock and cosmic dustComets move around the Sun in Elliptical orbitsWhen a comet passes close enough to the sun, solar radiation heats the water ice so that the comet gives off gas and dust in the form of a long tailComets always point away from the sun
4 CometsNHalley’s comet becomes visible to the unaided eye every 76 yrs as it nears the Sun.The Sun converts some of its gases into charged particles (ions), which stream away forming an ion tail.
5 Asteroids N Asteroids are large rocky bodies in orbit around the sun. Most asteroids have orbits that lie between the orbits of Mars and JupiterDangerous to us?Asteroid Ida is 55 miles long & orbits in the asteroid belt
6 MeteoroidsNMeteoroids are similar to Asteroids but much smaller in size.If a meteoroid enters the Earth’s atmosphere, it is called a meteorite.A Meteoroid entering the Earth’s atmosphere travels at great speeds, which heats up its surface and melts.
7 MeteorsNThis melting makes the meteoroid glow red hot and give off tons of light. We see this as “a shooting star”.The bright streak of light caused by a meteoroid or comet dust burning up in the atmosphere is called a meteor.
8 Meteor ShowersQuestion on video:“Meteor Showers” occur when Earth passes through the dusty debris left behind in the orbit of a cometN
9 Eclipses – Where R U ?NEclipses occur when the shadow of an object in the sky (ex. Moon, Earth) falls on another objectTwo types of Total Eclipses:Lunar Eclipse – Moon is hiddenSolar Eclipse – Sun is hiddenSometimes only a part of the Sun or Moon is hidden and this is a Partial Eclipse
10 Lunar EclipseNOccurs when the Moon passes through some portion of the Earth’s shadow.The shadow caused by an eclipse is an UMBRAThe moon appears red as it receives some light reflected off the Earth.Happens at night