1. Our Solar System

2. The Sun
The Sun is our home star; the center of the solar system which the planets and other bodies orbit
The Sun is by far the largest object in the solar system; it accounts for 99.7% of the solar systems mass

3. Terrestrial Planets
Terrestrial planets are the planets closest to the Sun
They are made mostly of rock and metal, have solid outer surfaces, and can have oceans and an atmosphere
Very small compared to gas giants

4. Planets: Mercury First terrestrial (rocky) planet
The smallest planet in our solar system
No moons
No atmosphere due to proximity to the Sun
Surface temp. up to 450°

5. Planets: Venus Second planet from the sun Terrestrial/rocky
Thick atmosphere of 97% carbon dioxide
Runaway greenhouse effect gives Venus average surface temps. Of 460°
On Venus it rains acid instead of water and lead melts and flows like water!
No moons

6. Planets: Earth The “Third Rock from the Sun” Terrestrial/rocky
Thick atmosphere of nitrogen and oxygen
Only planet confirmed to have surface liquid water
Only planet confirmed to harbor life!
One, very odd, Moon

7. Planets: Mars 4th planet from the Sun Terrestrial/rocky, 2 moons
Thin atmosphere of carbon dioxide
Confirmed to have ice at its poles, strong evidence that liquid water once flowed on Mars
Scientist speculate life may have also originated on Mars in the very distant past and may still be home to a few very specialized microbes!

8. The Asteroid Belt
The asteroid belt separates the inner and outer solar system
It is between Mars and Jupiter
The asteroid belt is populated by millions of irregularly shaped rocky objects called asteroids
The is a dwarf planet inside the asteroid belt called Ceres.
It is the only dwarf planet outside the Kuiper belt
Unlike all other asteroids, Ceres is a sphere

9. Gas Giants Much larger than the terrestrial planets
Mostly made of hydrogen and helium gas
They produce a large gravitational pull
The Gas Giants: Jupiter, Saturn, Uranus, Neptune
Some data suggests that large moons of gas giants has liquid water and may harbor life.

10. Planets: Jupiter 5th planet from the Sun
Largest planet in the solar system
The planet is mostly hydrogen and helium gas and possibly has a small, rocky core
Has 63 moons, the most in the solar system
Jupiter is famous for its red spot which is is a storm twice the size of Earth which has been raging for at least all of recorded history.
Some scientists hypothesize that Jupiter is a failed star!

11. Planets: Saturn 6th planet from the Sun
Mostly hydrogen and helium most likely with a rocky core
Has 60 moons
Most well known for its characteristic rings
Saturn has the largest most complex rings of any planet in our solar system
Saturn's largest moon Titan is the only moon known to have an atmosphere

12. Planets: Uranus 7th planet from the Sun
Made of hydrogen, helium, and methane
Has 27 moons
Has small, dim rings
Only planet with a tilted orbit around the Sun

13. Planets: Neptune Very similar composition to Uranus
The two planets are almost twins, except Neptune is more frozen
Has 13 moons
Has very faint rings
The last planet discovered in our solar system thus far

14. The Kuiper Belt
The Kuiper Belt is like a second, larger asteroid belt past Neptune. Consists of small rocky/icy objects as well as most of the dwarf planets
Dwarf Planets in the Kuiper Belt: Small, terrestrial planetoids; Pluto, Makemake and Haumea, Eris (the largest known dwarf planet)
Pluto

15. Comets and The Oort Cloud
Comets: small, icy objects mostly found in the far reaches of our solar system in the Oort Cloud; occasionally they are thrown into the inner solar system by the gravity of Neptune and other objects.
The Oort Cloud is basically the end of our solar system, although there are gas clouds past it in interstellar space
Haley’s Comet

18. Hypothetical Solar System Objects- Not part of notes!
Planet X:
The ancient Sumerians referred to it as Nibiru and listed in their diagrams of the solar system
Scientists have collected data which points towards its existence, but have by no means confirmed it.
Postulated forms of Planet X include:
a roughly Earth-sized, terrestrial or icy planet in the Kuiper Belt past Pluto
A 5th gas giant planet beyond Neptune known as Tyche
a brown dwarf star called “Nemesis” in or past the Oort cloud that is our Sun’s binary partner (most solar systems have 2 stars i.e. the are binary)
and even speculations that Planet X is a giant terrestrial planet inhabited by extraterrestrials!
Vulcan: a tiny hypothesized planet or dwarf planet between the Sun and Mercury. We have looked, but no one has found it!

19. Effects of Orbits
Ocean tides are caused by the gravitational force of the moon and the sun. As the moon orbits Earth and the Earth orbits the sun, water in the ocean is pulled up and down by gravity.
Seasons are caused by the by the tilt of the Earth on a 23.5° axis relative to the sun. As the Earth orbits, the sun light does not hit the northern and southern hemispheres equally.

20. A closer look at seasons

21. A closer look at seasons

22. Eclipses and Moon Phases
The moon goes through phases – lunar cycles of more or less light on the surface – due to the shadow of Earth cast by the sun as the moon orbits Earth
Lunar Eclipse: when the Earth passes directly between the sun and the moon, causing complete darkness
Solar Eclipse: when the moon passes between the Earth and the Sun the moon completely blocks the Sun (its weird that the Moon is positioned to perfectly cover the Sun during these eclipses)
There was a total solar eclipse in most of South Carolina on August 21, 2017
There is not an eclipse every time the moon orbits the Earth because the moon’s orbit is not in the same plane as the Earth’s orbit around the Sun

23. Days and Years
What we call a “day” is the roughly 24 hour period it takes the Earth to rotate once around it’s axis .
What we call a “year” is the roughly 365 days it takes for the Earth to orbit the Sun 1 revolution.
Technically those would be “Earth days” and “Earth years”; days and years would be different lengths of time depending on the planet you are on.