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COMPOSITION
ROCKY PLANETS (Mercury - Venus - Earth - Mars - Pluto)
The rocky planets are mostly made up of rock and metal. These planets are very heavy and move slowly. They also do not have rings and very few moons.
GAS PLANETS (Jupiter - Saturn - Uranus - Neptune)
The gas planets are mostly made up of gases (hydrogen and helium). These planets are light for their sizes (just like a big air balloon) and move quickly. They have rings and lots of moons.
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SIZE
SMALL PLANETS (Mercury - Venus - Earth - Mars - Pluto)
The small planets have diameters less than 13000 km across. Mercury and Pluto are sometimes referred to as lesser planets because they are so tiny.
GIANT PLANETS (Jupiter - Saturn - Uranus - Neptune)
The giant planets have diameters greater than 48000 km. The giant planets are sometimes also referred to as gas giants.
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Our solar system consists of the sun, eight planets, moons, dwarf planets (or plutoids), an asteroid belt, comets, meteors, and others. The sun is the center of our solar system; the planets, their moons, the asteroids, comets, and other rocks and gas all orbit the sun.
The nine planets that orbit the sun are (in order from the sun): Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto (a dwarf planet or plutoid). A belt of asteroids (minor planets made of rock and metal) lies between Mars and Jupiter. These objects all orbit the sun in roughly circular orbits that lie in the same plane, the ecliptic (Pluto is an exception; it has an elliptical orbit tilted over 17° from the ecliptic).
Easy ways to remember the order of the planets (and Pluto) are the mnemonics:
"My Very Excellent Mother Just Sent Us Nine Pizzas" and "My Very Easy Method
Just Simplifies Us Naming Planets" The first letter of each of these words
represents a planet - in the correct order.Add Comment