Astronomy Test 3 Flashcards
What type of star is the sun?
Main Sequence
What type of fusion occurs in the sun?
Nuclear Fusion
Core
Center of the sun; produce energy by fusing hydrogen into helium.
Radiative Zone
Located outside the core where energy moves outwards via radiation
Convective Zone
Hot gas rises and cools
Photosphere
Surface of the sun that we can see
Chromosphere
Inner layer of sun’s atmosphere
Corona
Thin outer atmosphere; easiest to see during a solar eclipse
Sunspots
Dark lower temperature spots on the sun’s photosphere
Solar Flare
Explosion of light and energy on the sun
Solar Wind
Stream of charged particles released from the sun
Prominence
Loops of gas that rise out of the sun’s corona
Granules
Bright regions formed by hot gases rising to the photosphere, spreading and cooling and falling back again
Why is it important to predict when sunspots and solar flares increase?
They affect astronauts, satellites, power grids, and communication devices.
What is a comet?
Icy ball that orbit the sun.
Meteor
passing through Earth’s atmosphere.
Meteorite
Portion of a meteroid that makes it through the atmosphere and strikes the earth.
Meteroid
Rock or icy fragments smaller than an asteroid. (in space)
What causes a comet’s tail?
As a comet approaches the sun it forms a gas/dust coma (or the tail) due to solar wind.
what direction does a comet’s tail point and why?
Away from the sun due to solar wind.
What is the name of the early model of our Universe that was Earth centered? Who came up with this model?
Geocentric; Ptolemy
What does Heliocentric Universe mean? Who came up with this model?
Sun-centered; Copernicus
What planet has the hottest surface temperatures caused by a dense atmosphere trapping heat (runaway greenhouse effect)?
Venus
What is an asteroid? Where are most asteroids found?
Solid rock-like mass that orbits the sun; most can be found in the Asteroid Belt between Mars and Jupiter.
What are Kepler’s 3 Laws of Planetary Motion?
1st
Planets move in ellipses with sun at one of the foci.
2nd
Planets in their orbits sweep out equal areas in equal time.
3rd
Periods of an orbit (in years) squared is equal to the semi-axis of the orbit (in AU) cubed.
What is Olympus Mons? Where is it found?
Volcano (shield); MarsVolcano (shield); Mars
Define Rotation
An object spins on its axis.
Define Revolution
An object moves around another object (such as the sun).
Which planet has the shortest day?
Jupiter
Which planet is tilted on its side?
Uranus
Which planet has a day longer than its year?
Venus
What is the largest moon in our Solar System?
Ganymede
What type of satellite completes one orbit of the Earth in about 24 hours?
Geostationary. It travels with the earth’s rotation.
Discuss the contributions of the space program to technology and society.
The space program helps advance technology and increase public safety in cars and aircrafts.
What type of satellite passes over a different portion of the Earth’s surface each orbit?
Polar satellite (travels around the earth from North to South Pole).
Name the 5 largest moons in the Solar System (hint: four are the Galilean moons of Jupiter, and the fifth is the Saturn’s large moon).
Jupiter’s 4 moons: Ganymede, Io, Gallisto, Europa, and Saturn’s moon: Titan
