/Notes/ Planets NASA
Jan 02, 2016
/Notes/ PlanetsNASA
Th
e s
tory
so
far:
NASA
Protoplanetary disk
Gas and dust left-over after the formation of the
star.
NASA
http://www.maths.qmul.ac.uk/~masset/movies/flyby.png
Gravity
Begins pulling together
bits of rock and gas
Gravity
NASA
NASA/JPL-Caltech/T. Pyle (SSC)
Planetesimals
Baby planets
NASA
They’re violent
NASA
NASA/JPL-Caltech/T. Pyle (SSC)
Planets form
Planetesimals combine and grow larger until they become planets
What is a planet?
NASA
1. Orbits the Sun
The Moon (not a planet)
NASA
NASA
2. Large enough for gravity to make it round
Phobos (a moon of Mars- not a planet) NASA
Moon
Phobos
Earth
Moon
3. Has “cleared it’s neighborhood” of debris
Pluto (not a planet) NASA
Types of Planets
NASA
Gas GiantsNASA
Made mostly of hydrogen and helium
NASA
May not have any solid ground
Probably no surface like on the Earth
NASA
All have rings and many moons.
NASA
Jupiter
Saturn
Uranus
Neptune
Terrestrial Planets
NASA
Are made of rocks similar to the Earth
NASA
All have iron cores
NASA
Have craters from asteroids and comets
NASA
NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Mercury
NASA/NSSDC
Venus
NASA
Earth
NASA
Mars
http://www.kiroastro.com/writings/perspective
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
Dwarf Planets
Orbit the Sun
NASA
Are large enough for gravity to make them round
NASA
Have NOT cleared their neighborhood
NASA
A new type of planet
Only used since August, 2006
NASA
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
http://commons.wikimedia.org/wiki/File:TheTransneptunians_Size_Albedo_Color.svg
Earth
Extrasolar Planets
• Extrasolar Planet- a planet orbiting a star other than the Sun
– As of Feb. 10, 2009:• 340 planets around other stars have been
discovered– Source: http://exoplanet.eu/catalog.php
http://commons.wikimedia.org/wiki/File:Exoplanets_en.svg