OUTCOME QUESTION(S): S1-4-08: What objects make up our solar system and Universe? Vocabulary and People Asteroid beltKuiper beltMoon AsteroidMeteoroidMeteor MeteoriteComet

Outer region of nebula: Gases (far from forming Sun) begin to cool Cluster together and condense Forming the Gas Giants: Jupiter, Saturn, Uranus and Neptune Formation of our Solar System All matter recycled from past supernova explosions Gas Giants appear to lack solid surfaces, but the gases may become liquid or solid deeper towards their dense core

Inner region of nebula: Gases in the inner region too hot to condense Chunks of iron and rock collide and stick together Forming Terrestrial Planets: Mercury, Venus, Earth and Mars “Terrestrial” planets have a surface of rock, iron and hard elements through to the molten core

Terrestrial planets

 Closest to the Sun Receives sunlight 10x brighter than Earth Day temperatures over 400°C  No atmosphere - so night temp fall to -180°C Day (rotation) – 59 Earth days Year (revolution) – 88 Earth days Mercury It rotates so slowly that its “year” is less than 2 “days” long

 3 rd brightest object in the sky CO 2 atmosphere traps heat (+ 465°C) Many volcanoes eject tonnes of sulphur  Clouds of sulphuric acid – makes acid rain Day (rotation) – 243 Earth days Year (revolution) – 225 Earth days Venus Sun and Moon are brightest objects Its “year” is shorter than its “day”

 Atmosphere (N 2, O 2, H 2 O) stabilizes temperature Ranges from -85 o C to +65 o C  Liquid water covers about 70% of surface Generally stable – some volcanoes, earthquakes Day (rotation) – 1 Earth days Year (revolution) – 365 1/4 Earth days Earth Distance from the Sun is most responsible for the factors that contribute to Earth’s ability to sustain life

 Bright red - iron oxide dirt makes it reddish Most studied planet (no signs of life… yet )  Of all planets, Mars is most like Earth Surface temp ranges from -120 o C to +30 o C Day (rotation) – 1 Earth day Year (revolution) – 687 Earth days Mars Although it is dry and barren now, scientists have evidence that may point to past glaciers and liquid water

An Asteroid Belt separates the Terrestrial planets from the Gas Giants – maybe remains of a totally smashed older planet

The Gas Giants Look at the shadow of a moon on the picture of Jupiter

 Largest of the planets (11x bigger than Earth). Has 63 moons (2006)  Great Red Spot is a continuous hurricane Temp around -160 o C Day (rotation) – 10 Earth hours Year (revolution) – 11.9 Earth years Jupiter The coloured bands are gas clouds being streaked over the surface as it rotates quickly

2 nd largest of the planets  Least dense – may not have a solid core  Rings stretch from Earth to Moon 60 moons and 1000 rings (could be crushed moon) Day (rotation) – 11 Earth hours Year (revolution) – 29.5 Earth years Saturn Notice the coloured bands on the surface here too 3 moons and a shadow in this picture

 Rotates on its side Extremely cold -210 o C  Has several narrow, dark rings Has 27 moons Day (rotation) – 17 Earth hours Year (revolution) – 84 Earth years Uranus It is now pronounced “ur-an-is” not “ur-anus”

Only discovered because its gravity “tugs” on Uranus’s orbit causing changes  Blue and white – methane in atmosphere  The Great Dark Spot is a gigantic storm Extremely cold -220 o C Day (rotation) – 16 Earth hours Year (revolution) – 165 Earth years Neptune Neptune has some faint rings too, and 20 moons

Kuiper Belt and the Oort Cloud Contain thousands of icy and rocky objects Kuiper Belt – Neptune to about 30 to 55 AU Oort Cloud – from 5000 AU to AU  Pluto and Eris are the best known dwarf planets found in Kuiper belt Pluto was reclassified as a dwarf planet in 2006

Moon: Large natural object (rock/metal) that revolves around a planet – also called a satellite. The Roman goddess of the moon was Luna Planet (2006)Known moons Mercury0 Venus0 Earth1 Mars2 Jupiter63 Saturn60 Uranus27 Neptune13 Pluto3 Humans have visited the moon’s surface six times between 1969 and 1972.

Asteroid: Chunk of rock/metal that orbits the Sun but too small to be considered a planet. Asteroids can get bumped and smashed into a new orbit and sometimes that orbit can get “close” enough to be pulled in by Earth’s gravity. Asteroid belt in large gap from Mars – Jupiter Largest is 1000 Km in diameter Asteroid that crosses Earth’s path called a Trojan

Meteoroid: lump of rock that is trapped by Earth’s gravity and pulled into the atmosphere. The only difference between meteoroid and asteroid is that a meteoroid is random and an asteroid orbits the Sun Falling meteoroids bump into air molecules heating up (friction) until the air glows – and the meteoroid burns up and breaks apart. Meteoroid that completely burns up - meteor producing a streak of light - “shooting star”

Meteorite: fragment of a meteoroid that doesn’t burn up and strikes the Earth (space rock). Large meteorite collisions make craters Westhawk Lake is a crater Meteorite impact crater in Arizona

Comet: chuck of ice/dust that orbits the Sun. Most originate from the Oort cloud Tail: passing by Sun heats trailing gas and debris then blown out by solar wind - millions of km long Some have regular periods of revolution Halley’s comet: last seen in 1986 it has a orbit period of 76 years

CAN YOU ANSWER THESE QUESTIONS? S1-4-08: What objects make up our solar system and Universe? Vocabulary and People Asteroid beltKuiper beltOort cloud MoonAsteroidMeteoroidMeteor MeteoriteComet