Chapter 23: Our Solar System
What are the criteria that an object has to meet to be called a dwarf planet?
-orbits the sun -are rigid and can be nearly spherical -can share its orbit with other objects -are not satellites (moons)
What are the criteria that an object has to meet to be called a planet?
-orbits the sun -has a spherical shape -does not share the space of its orbit with any other object of significant size (other than moons)
How many moons does Mercury have?
0 (Mercury)
How many moons does Venus have?
0 (Venus)
How many moons and rings does Uranus have?
13 faint rings in 27 moons.
What is Pluto's orbit tilt?
17 degrees to the elliptical. Its orbit is more elliptical than other planets.
How many moons does Mars have?
2, Phobos and Deimos
How much more matter does Jupiter contain than everything else in the solar system excluding the Sun?
2.5 times the amount of matter
How many objects in our solar system are classified as dwarf planets and what are they?
5; Pluto, Ceres, Haumea, Makemake, and Eris
How many objects in our solar system are planets by definition?
8 objects are planets: Mercer, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
*What does Pluto form with its largest moon Charon?
A binary or double planet
What is it called when we see a comet appear again at regular intervals?
A periodic comet
What type of magnetic field does Jupiter have?
A very strong magnetic field
What Jovian planets have rings?
All Jovian planets
What is a planet's path around the sun called?
An elliptical orbit
How many moons does Jupiter have (that we know of)
As of 2021 Jupiter has 79 confirmed moons.
How does Venus rotate respectively to other objects in the solar system?
Backwards
What is Venus's atmosphere mostly composed of?
Carbon dioxide with smaller amounts of nitrogen and water vapor.
What is Ceres' classification?
Ceres is classified as both an asteroid and a dwarf planet.
What are meteoroids?
Chunks of rock smaller than asteroids. (Are asteroids just smaller)
We can classify our planets based on what? (2 ways)
Composition and position
What is the third planet from the Sun?
Earth
What is the only planet not classified in the position category?
Earth (It is neither inferior nor superior)
What is the only planet not named after a Roman god?
Earth, was named from Old English and German words for ground.
What is interesting about Europa?
Europa has an icy crust and they believe that there is liquid water underneath it. It is one of the few places in our solar system where life might exist.
What is the largest moon in our solar system and where is it located?
Ganymede is the largest moon and it is larger than the planet Mercury. It orbits Jupiter but it would be considered a planet if it primarily orbited the Sun.
What is Jupiter mainly composed of?
Hydrogen and Helium (Since it's mostly gas, its density is ¼ that of Earth's)
What are meteorites?
If part of the meteor actually hits the Earth, the part that lands on the Earth is this.
Where do most asteroids orbit?
In a belt between Mars and Jupiter called the asteroid belt.
Where are Haumea, Makemake, and Eris located?
In the Kuiper Belt which is far beyond Neptune
Where is Ceres located?
In the asteroid belt between Mars and Jupiter
What are the two groups/categories in the position classification?
Inferior planets and Superior planets
What are the names of the Galilean moons?
Io, Europa, Callisto, and Ganymede.
What is odd about Uranus's axial tilt?
It is 97.8 degrees so it seems to be laying on its side.
What is a moon?
It is a rocky object that orbits another body in our solar system.
What is the surface of mercury like?
It is a rocky surface plain that is smooth and relatively crator~free.
How dense is Saturn?
It is less dense than water so if you put it in a big pool it would float.
Where is the largest volcano in our solar system located, what's its name, and what's its size/type?
It is on Mars, it is called Olympus Mons, it is a shield volcano, and the base is larger than the state of Colorado and it is 3 times higher than Mount Everest.
What's Neptune's size and density compared to Uranus?
It is slightly smaller and denser than Uranus.
What is Uranus named after?
It is the only planet named after a Greek god. It is named after the Greek sky god.
Why would you not want to go to Venus?
It is very hot, has acid rain, it has very high atmospheric pressure (you will be crushed), and it does not have a magnetic field so everything from space will hit you including the sun's radiation.
How was Neptune discovered?
It was discovered when astrophysicists noticed that something was exerting a gravitational force on Uranus. They calculated where the unknown object should be and they were only one degree off from where it was.
What is Uranus's atmosphere mostly made out of?
Its atmosphere is mostly hydrogen and helium but both are colorless.
What is Jupiter's diameter and mass compared to Earth?
Its diameter is 11.2 times that of Earth and its mass is 317.8 times that of Earth
What is the fifth planet from the Sun?
Jupiter
What is the third brightest nonluminous body in the sky?
Jupiter is 3rd brightest
What is the largest planet in our solar system?
Jupiter is the largest planet
What are the names of the Jovian Planets?
Jupiter, Saturn, Uranus, and Neptune
What is the fourth planet from the Sun?
Mars
What is the closest planet to the Sun?
Mercury
What's planet in our solar system has the biggest nighttime vs. daytime difference?
Mercury has the biggest nighttime vs. daytime difference
How large is Mercury's atmosphere and what is it made of?
Mercury's atmosphere is very thin and is constantly replaced by the solar wind. The gases in the atmosphere mostly consist of oxygen, sodium, and hydrogen.
What are the names of the terrestrial planets?
Mercury, Venus, Earth, in Mars.
What is the difference between meteoroids, meteors, and meteorites?
Meteoroids are out in space, meteors are in our atmosphere, and meteorites are when the rock hits the Earth.
What are asteroids that orbit the Earth called?
Near~Earth asteroids (NEA)
How many moons and rings does Neptune have?
Neptune has 14 moons but only two are observable from Earth and at least four faint rings.
What is the 8th and most distant planet from the sun?
Neptune, orbits almost 4.5 billion km away from the Sun
What are meteors?
Occasionally meteoroids will pass through the atmosphere in their orbit. Friction with the atmosphere heats the rug and makes a bright streak of light in the night sky.
How many times does Mercury rotate when it orbits around the Sun?
Only one and a half times for each full orbit
What are inferior planets (definition) and what are their names?
Planets closer to the Sun than Earth. Their names are Mercury and Venus.
What are superior planets (definition) and what are their names?
Planets further from the Sun than Earth. They are Mars, Jupiter, Saturn, Uranus, and Neptune.
What are terrestrial planets? (Definition)
Planets that are about the same size and density as Earth (the 4 smaller planets in our solar system).
What are Jovian Planets? (Definition)
Planets that are larger than Earth, have low densities and are made mostly of light Elements, gases, and ices. (also called gas giants)
*What did the Cassini spacecraft detect on Saturn's moon Enceladus?
Plumes of water being ejected
What is Pluto's classification?
Pluto is classified as a dwarf planet. It used to be classified as a planet.
What is interesting about Pluto's orbit (With Neptune)?
Pluto is closer to the sun than Neptune during its perihelion.
Why is Pluto no longer considered a planet?
Pluto was reclassified by the IAU as a dwarf planet. (Also, it doesn't clear out its orbit)
*What was Mercury named after?
Roman Messanger God
What was the planet Venus named after?
Roman goddess of beauty and love
What is the sixth planet from the Sun?
Saturn
How many major rings does Saturn have?
Saturn has 7 major rings and thousands of smaller rings. These rings are Saturn's most defining feature.
*How is Saturn similar to Jupiter?
Scientists believe its interior structure is similar to Jupiter's and it has the same fast-moving bands of clouds when Jupiter. Saturn also has a seasonal storm called the Great White Spot.
What are moons, dwarf planets, and anything else that is not considered a planet called?
Small Solar System Bodies (SSSB)
What are comets?
Small solar system bodies made of rock and ice that orbit the sun
What are the two groups/categories in the composition classification?
Terrestrial planets and Jovian planets
In the orbit of a planet, what is the farthest point from the sun called?
The Aphelion
What is the name of the huge storm on Jupiter that is several times the size of Earth?
The Great Red Spot
How old is the Great Red Spot and who/when was it discovered?
The Great Red Spot is at least 354 years old and was first seen by the astronomer Cassini in 1665.
What is the name of Earth's moon?
The Moon
In the orbit of a planet, what is the closest approach to the sun called?
The Perihelion
What are Saturn's rings composed of?
The Rings average only about 20 meters sick and are made mostly of water ice pieces. The sizes range from microscopic particles to house-sized chunks.
What is Saturn named after?
The Roman god of agriculture
What was Neptune named after?
The Roman god of the sea
What is the main difference between planets and dwarf planets?
The dwarf planets neighborhood.
What happens when a comet moves away from the Sun?
The ice freezes again and the comet is no longer visible without a telescope.
What happens when a comet's orbit carries it toward the sun?
The ice melts and then blows off as gas caring bits of rock and dust with it. The solar wind pushes against the fine matter and carries it away forming one or more bright tails.
What does our solar system include?
The sun and the. objects its gravity holds around it (our 8 planets and dwarf planets).
What are the four largest moons called and when were they discovered?
They are called Galilean moons and they were discovered by Galileo in 161-.
What are asteroids/their classification?
They are much smaller than planets, they don't have an atmosphere and can have odd shapes.
What do they believe Jupiter's interior is like?
They believe it has a rocky core surrounded by a deep layer of liquid metallic hydrogen
Why can't Pluto and other dwarf planets clear out the objects in their orbit?
They cannot because they do not have enough mass (gravity).
Why don't Superior planets ever transit the Sun?
They don't sin because they're never between us and the sun.
What do the clouds on Jupiter form?
They form bands that race around the planet and large storms exist where the bands touch.
* Why did the International Astronomical Union (IAU) meet in 2006?
They met to redefine and reclassify objects (possible planets in our solar system).
Where are other asteroids located and what are they called?
They orbit Jupiter and are called Trojan asteroids
What is the only moon in our solar system with a dense atmosphere?
Titan and it orbits Saturn
What is it called when we see inferior planets cross in front of the Sun?
Transit
What is the seventh planet from the Sun?
Uranus
What planet has the coldest atmosphere in our solar system?
Uranus and it is -215 degrees Celsius
What color does Uranus appear to be and why?
Uranus appears to be blue because of the methane in its atmosphere.
What is the second planet from the Sun?
Venus
What is the hottest planet?
Venus (460*C or 830*F)
Why can we not see Venus directly?
Venus is covered with thick clouds
* In 2005 a group of astronomers were studying telescope images of a starfield. They saw an object that wasn't moving like the other stars. After further studies were done they concluded that they had found what?
a 10th planet (Eris)
How many moons are orbiting Jupiter?
at least 62
What is Jupiter's atmosphere made out of?
gaseous hydrogen with clouds of ammonia and ammonia compounds
What type of atmosphere does Mars have?
it has a thin dusty atmosphere Mostly composed of carbon dioxide with a little nitrogen and Trace Amounts of other gases
What are the ice caps on Mars made of?
solid carbon dioxide (dry ice)
What is Mars named after?
the Roman God of War
What is Jupiter named after?
the Supreme Roman god
What is the average surface temperature on Mars?
~63*C or ~81*F