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Notes on video lecture:
What is a Moon?
Choose from these words to fill the blanks below:
wide, impact, combined, disk, increasing, Saturn, asteroids, gas, half, asteroids, liquified, comets, planet, formed, debris, star, Mercury
what is a moon?
a planet is an object that orbits a         
a moon is an object that orbits a             
some moons are shaped like                   
can be a quite small
we have not defined the cutoff point where a moon is a moon and not just             
our solar systems number of moons has been steadily                     
in the last 20 years we have found many new moons around Jupiter and             
the number changes on an annual basis
Earth has one moon
its origin is based on the giant              hypothesis
an object          as wide as the earth slammed into the earth very early on
this collision resulted in both objects being to a large extent vaporized and                   
the core of this object                  with earth's core
the rest of the material from that object and from the outer part of the earth splattered into space into a big          of debris that eventually consolidated to become the moon
Mars has two moons
a possibility that these moons are captured                   
Venus and                don't have any moons
the        giants, the large, bloated planets that orbit our Sun
their gravity and          orbits have enabled them to pick up many moons
some of the moons              in orbit around the planets
others are captured asteroids and             

Ideas and Concepts:

On the uniqueness of earth's moon, from tonight's Moons of our Solar System class: "It became evident that our moon was something else than just this odd object floating around the earth. It's a critical part of the earth-moon system, it really is a part of us. Out of any object in our solar system, our moon probably has the most complete and clear history available of the last 4.5 billion years of our solar system's development. And it is the only place in our solar system where we are likely to be able to go to find a piece of early earth."
From the myth busting department, via tonight's Moons of our Solar System class: "Myth:Only planets have moons. Wrong. Things smaller than planets can have moons as well, even asteroids only a few kilometers across can have a smaller asteroid orbiting them, such as the asteroid 243 Ida and its moon Dactyl. Also, Pluto is no longer regarded as a planet, yet it has five moons, and many other bodies in the solar system similar or smaller in size to Pluto are also known to have moons."
More myth busting via tonight's Moons of our Solar System class: "Myth:Without the moon, there would be no tides in the sea. False. The sun also exerts a tidal force on the earth's oceans. The sun contains much more mass than the moon, but it is also much further away, so that the sun's tidal force is about 46% of the moon's tidal force. Without the moon, the earth would experience twice daily tides, a bit less than one half the size of the actual tides."
On the origin of moons, via tonight's Moons of our Solar System class: "Venus and Mercury have no moons, while the gas giants, those large, bloated planets that orbit our Sun, have many moons since their gravity and wide orbits have enabled them to pick up many moons, some forming in orbit around the planets while others were captured as asteroids and comets. Mars has two moons, its proximity to the asteroid belt suggesting the possibility that these moons are also captured asteroids. The Earth, on the other hand, has one moon and the current understanding of its origin is based on the giant impact hypothesis:an object about half as wide as the earth slammed into the earth very early on in the earth's development, this collision resulting in both objects being vaporized and liquified, the core of the object combining with the earth's core and the rest of the material from that object splattering into space along with part of the earth's material forming a big disk of debris that eventually consolidated to become our moon."
What is a Moon?
The Icy Moons
Naming Moons