Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

30 Cards in this Set

  • Front
  • Back
What are the 3 lightest elements that were formed shortly after the creation of the universe?
The _______ elements were produces much later by stars and cast into speace when the stars died. By mass, 98% of the matter in the univers is __________ and __________.


When and how was the solar system created?
4.6 billion years ago

from swirling, disk-shaped clouds of gas, ice and dust called solar nebula.
The solar system was formed from swirling, disk-shaped clouds of gas, ice and dust called _______ _______.
solar nebula
How were the 4 inner planets formed?
Through accretion of dust particles into planetesimals and then into larger protoplanets.
How were the 4 outer planets formed?
Through the runaway accretion of gas and ice onto rocky protoplanetary cores.
What formed in the center of the solar nebula?
The 2 ________ planets of the solar system share many characteristics and are distinctly different from the four giant __________ planets and from pluto.
What is another name for inner planets?
Are the inners planets big or small?
Do the inner planets have high average densities or low?
What are the inner planets primarily composed of?
Rock and Metal
What two outer planets have large diameters and low densities and are composed of primarily hydrogen and helium?
Jupiter and Saturn
What two outer planets have large quantities of water as well as much hydrogen and helium?
Uranus and Neptune
What is pluto made out of?
Rock-ice composition
_________ are rocky and metallic debris in the solar system larger than about a kilometer in diameter.
_________ are smaller pieces of such rocky and metallic debris.
________ are debris that contain both ice and rock.
Astronomers have observed disks of _____ and _____ orbiting other stars.
How many extrasolar planets have been discovered?
How big are the extrasolar planets?
about the size of Jupiter
How are extrasolar planets discovered?
Indirectly, by their effects on the stars they orbit.
How many stars are there in the solar system?
1 sun
Was the solar system created as a direct result of the formation of the universe?
No, All matter and energy were created by the Big Bang. However, much of the material that exists in our solar system was processed inside stars that evolved before the solar system existed. The solar system formed billions of years after the Big Bang occurred.
How long has the Earth existed?
4.6 billion years
Is Pluto always the farthest planets from the Sun?
No. Every 250 years, Pluto Joins Neptune's orbit for 20 years and then it goes back to an elliptical orbit.
What typical shape do moons have?
While some moons are spherical, most look roughly like potatoes.
Have any Earthlike planets been discovered orbiting sunlike stars?
No, nearly all the planets discovered orbiting Sunlike stars are Jupiter-like gas giants.
Who do astronomers believe that the solar nebula was rotating?
B/c the astronomers have observed gas and dust orbiting around young stars.
What are the 4 methods for discovering extrasolar planets?
1. Radial Velocity method
2. Astronomic method
3. Transient method
4. Microlensing