Astronomical Units Astronomical Units are units that are used by astronomers to find differences between extraterrestrial objects. 1 AU or astronomical unit is 93,000,000 miles or the distance from the Earth to the sun. For example, Jupiter is 5.2 AU away from the sun. That is 483,600,000,000 miles away from the sun.

Sun Our Brightest Star Approximately one million Earths can fit inside the Sun. The sun is a ball of extremely hot gas. Much different then the Earth’s, the sun has it’s own unique atmosphere It is the source of heat and light for all the planets in the Milky Way Galaxy.

Our Solar System Consists of eight planets. 4 terrestrial (land planets) and 4 gas planets All revolve around the Sun, which is the main source of light and heat for these eight planets. It is the Sun's strong pull of gravity which keeps the planets in orbit around it.

The Terrestrial Planets

Mercury Mercury Our Fastest Planet The closest Planet to the Sun. Only a little larger than our moon. It is covered by dust, rocks, and craters. Time it takes to rotate on it’s axis,59 days (DAY and NIGHT). Time it takes to revolve around the sun, 88 Earth days (YEAR). Mercury can reach a high of 800 degrees and a low of about 300 degrees Fahrenheit.

Venus Venus Our Hottest Planet Time it takes to rotatae on it’s axis, 243 Earth Days (DAY/NIGHT) Time it takes to revolve around the sun, 225 Earth days (YEAR) On Venus a day is slightly more than a year. About the same size as Earth. Has mountains, valleys, and plains. The heat is about 450 degrees Celsius. Has no water. Life as we know it could not survive here. Only rocks can handle the high temperature and crushing pressure.

Earth Our Mother Planet 70% of its surface is water& the other 30% is land. It’s tilt causes the seasons on the planet. Earth is the only planet in the universe which is known to support life. Earth is almost five billion years old. The center of the Earth, its core, is molten. Earth is the only planet in the Solar System known to be geologically active.

Mars Our Angry Red Planet The largest volcano in the Solar System is on Mars, called Olympus Mons. Mars has seasons like Earth. This is caused by the tilt of the planet's axis, at a similar angle to the tilt of Earth's axis Rocks from Mars have landed on Earth from meteorite impacts blasting debris through space. The average temperature on Mars is about -67 °F. Time it takes to rotate on it’s axis, 24.5 Earth hours (D&N) Time it takes to revolve around the sun, 687 Earth days ( YEARS)

Jupiter Our Largest Planet Earth could fit into Jupiter over 1300 times! Jupiter is made up almost entirely of gas. Jupiter's famous Red Spot is a great storm that has raged for at least four hundred years. Jupiter has a thin set of rings, hardly visible from Earth. Jupiter has the strongest pull of gravity in the Solar System. If we were able to stand on the surface of Jupiter, we would weigh three times as much as we would on Earth. Time it takes to rotate on it’s axis, 9 hrs. 56 mins. Earth hours (D&N) Time it takes to revolve around the sun,4,333 Earth days (YEAR)

Saturn Rings of Beauty Saturn is the second largest planet. The many moons of Saturn are as different as fire and ice. There are at least 24 of them. Saturn's rings are believed to be the particles of an old moon orbiting the planet, smashed apart in a collision about 50 million years ago. Saturn is twice as far away from the Sun as Jupiter is. Time it takes to rotate on it’s axis, 10.5 Earth hours (D&N) Time it takes to revolve around the sun, 29.5 Earth years (Year) (10,767.5 Earth days)

Uranus Georgian Planet Uranus is the only planet in our solar system to rotate on its side. Has 11 thin (rock fragment) rings and over 20 known moons Uranus' pale blue color is caused by the methane in its atmosphere which filters out red light. Time it takes to rotate on it’s axis, 17 Earth hours and 14 Earth minutes. (D&N) Time it takes to revolve around the sun, 84 Earth years (YEAR) (30,660 Earth days)

Neptune Neptune sometimes orbits the Sun further away than Pluto making it the most distant planet in the Solar System. Blue coloring due to methane in it’s atmosphere Has a 4 faint rings and 13 moons Since its discovery in 1846, Neptune has not yet completed a full orbit. Time it takes to rotate on it’s axis, 16 Earth hrs. and 27 Earth mins. (D&N) Time it takes to revolve around the sun, 165 Earth years (60,225 Earth days) Neptune has the strongest winds in the Solar System, and a dark spot, similar to Jupiter's Great Red Spot.

Pluto Our Tiniest Planet Pluto is a dwarf planet, composed of rock and ice 2/3rds the size of Earth’s moon. Is a dwarf planet – because it can not move other space objects in its path Pluto has its own moon, Charon. Time it takes to rotate on its axis, 6 Earth days + 9 Earth hrs. Time it takes to revolve around the sun, 248 Earth years (90,520 Earth days)

ARE THERE ANY OTHER PLANETS OUT THERE? A plutoid is a dwarf planet that is farther out in space than the planet Neptune. The four known plutoids are Pluto, Eris, Haumea and Makemake (MAH-kee-MAH- kee)

Why is Earth most suitable for life? Earth’s distance from the Sun + Earth’s greenhouse effect in the atmosphere – allows us to live in the perfect temperature Earth is mostly covered by liquid WATER. –Liquid Water = most necessary for life Earth is composed of rock and water –terrestrial planet

Mars ? –Discovered water on Mars, supports evidence that their may be life there –Will send humans next to Mars to try to find more evidence of life. ANY LIFE OUT THERE? Moon ? –Little evidence of water –Little evidence of oxygen. –No life has been detected or found.