Download Astronomy Final Study Guide - With Answers!!– Name: **This will be

Astronomy Final Study Guide - With Answers!!– Name: ____________________________________
**This will be the biggest test we have taken this year. I recommend using this study guide wisely to analyze
what you already know well. Ask your friends questions. Quiz each other. Ask me questions. There is no point
in copying each other because this is not a homework assignment, but it will help you prepare for the test. I will
be in before school tomorrow if you have more questions. You can also email me questions!**
Email: [email protected]
Vocabulary terms to know:
Multistage Rocket
Wavelength
Frequency
Waxing/Waning
Crescent/Gibbous
Revolution/Rotation
Absolute/Apparent Brightness
Parallax
Protostar, Main Sequence Star, Red Giant, Supergiant, Planetary Nebula, Nebula, Supernova, White Dwarf,
Black Dwarf, Neutron Star, Black Hole
Light Year
1. What are some of the advantages and disadvantages to using both multistage rockets and space
shuttles?
Multi-stage rockets: Can travel farther, more maneuverable, and use less fuel than single-stage rockets.
Space Shuttles: Are reusable – can go to space and land like an airplane. Disadvantage: can only stay in
the earth’s orbit – can’t travel to the Moon or other planets.
2. What was the name of the first ship in space? Why was it significant? (who launched it and why did we
care??)
First spacecraft in space – Sputnik 1. This was launched by the Russians and it was significant because we
were in the Cold War with the Russians at the time. We were scared that if they could launch a rocket
into space, they could definitely bomb us!
3. Where do our space shuttles currently go when they get launched into space?
Our space shuttles, although only one shuttle launch is left, go to the International Space Station to do
research and tests.
4. List out the electromagnetic spectrum using energy levels from highest to lowest (or lowest to highest)
High to Low: Gamma, X-Ray, Ultraviolet, Visible, Infrared, (Microwave), Radio
5. How does energy affect the frequency, wavelength, and speed of a wave?
The higher the energy, the shorter the wavelength and the higher the frequency. The energy of a wave
does not affect the speed of a wave – they all travel at the speed of light.
6. Order the colors by their energy levels. What person can help you do this?
Low to High: Red, Orange, Yellow, Green, Blue, Indigo, Violet – ROYGBIV
7. What is the Doppler Effect? What does it tell us about the Universe? How are red shift and blue shift
different?
The Doppler Effect describes how waves are changed when objects are moving. When an object is
moving toward you, the waves become higher-pitched or have a higher frequency. This causes a “blue
shift” because blue has more energy and a higher frequency. When objects are moving away from you,
the waves become lower pitched and have a lower frequency. This is called a “red shift” because red has a
low frequency. Most objects in the Universe have a red-shift, which leads to us thinking the Universe is
expanding.
8. What are the differences between asteroids, comets, meteoroids, meteorites, and meteors?
Asteroids are small rocks that orbit the Sun like planets. Most are found in a belt between Mars and
Jupiter.
Comets are “dirty snowballs”. They are made of ice, dirt, and dust and have very elliptical orbits. When
they get near the Sun, they form a tail that points away from the Sun. The tail is gas that is heated by
the Sun.
Meteorites are meteoroids, or very small pieces of rock that are large enough to break through the
earth’s atmosphere and hit the earth.
Meteors are meteoroids that get burned up by the atmosphere. These are called “shooting stars”
9. How are spiral, elliptical, and irregular galaxies different? What are the parts of a galaxy?
10.
11.
12.
13.
We live in a spiral galaxy. Spiral galaxies usually have a lot of gas and dust in their spiral arms for new
stars to form there. Irregular galaxies don’t have a definite shape (maybe because they are very young),
and elliptical galaxies are older galaxies that do not have very much gas or dust, so they do not create
new stars very often.
Approximately how many galaxies are there? How many stars are in a galaxy?
Scientists estimate that there are billions of galaxies in the Universe! In each galaxy, there are most
likely billions of stars. In the Milky Way galaxy, it is estimated that there are between 200 and 400
billion stars.
What is nuclear fusion? What does it produce?
Nuclear fusion is when small elements, with enough heat and pressure, combine to form larger
elements. Usually four hydrogen atoms combine to form a helium atom, with energy left over.
Nuclear fusion produces heat, energy, light, and larger elements.
Why are both density and temperature important for nuclear fusion to take place?
Hydrogen atoms are positively charged, which means that when they get close to each other, they repel
away. In order to get them close, there must be tremendous pressure pushing in on the atoms. To get
the atoms moving fast enough so that when they collide, they combine together, it must be incredibly
hot.
How are solar winds, solar flares, sunspots, and prominences different?
Solar winds are charged particles that travel toward the earth from the Sun.
Sunspots are dark patches on the Sun’s surface that are dark because they are cooler than surroundings.
Prominences are big loops of gas on the Sun’s surface that sometimes connect sunspots.
Solar flares are huge eruptions of gas from the Sun’s surface that are sometimes caused by prominences
joining together.
14. What causes a solar and lunar eclipse? Why don’t they happen every month?
Solar eclipses are caused by the moon coming directly between the earth and the Sun, and the Sun’s
shadow showing on the earth. Lunar eclipses are when the earth passes between the moon and the Sun,
and the earth’s shadow covers the moon. The reason why they do not happen every month is because
the moon’s orbit is tilted about 5 degrees, so the shadows usually do not line up.
15. What causes the earth’s tides? What is the difference between spring and neap tides? Be able to draw a
picture explaining why spring/neap tides happen.
The earth’s tides are caused mostly by the gravitational pull from the moon. Wherever the moon is, we
will have a high tide. Spring tides happen when the sun, moon, and earth are all lined up in a straight
line. During a spring tide, we have very high high tides and very low low tides. There is a huge difference
between high and low tides because the moon and sun are working together to pull on the earth’s
water. Neap tides happen when the sun, moon, and earth are at a 90 degree angle. The moon is pulling
one way and the sun is pulling in another way. This means that there will not be a large difference
between high and low tide.
16. What causes the seasons on Earth? Why are we soon going to have Summer? What season is it in the
Southern Hemisphere when we have Summer?
The earth’s seasons are caused by the earth’s tilted axis. Because the earth is tilted in comparison to the
sun, different parts of the earth get more or less direct sunlight during the year. We are going to have
summer because the Northern Hemisphere will be pointed toward the sun. This will give us direct
sunlight and warmer temperatures. In the Southern Hemisphere it will be winter during our summer.
17. Moon’s phases – be able to name/draw the phases in order.
New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last
Quarter, Waning Crescent
18. Be able to draw lines in a parallax diagram and show what the stars would look like from the Earth.
19. Know the life cycle of a star diagram and be able to put the stages in order and label each stage.
20. How are rotation and revolution different? How are they similar in the case of the Moon? Why is this
weird?
Rotation is when an object spins on its axis. When it spins once on its axis, we call it one day.
Revolution is when an object travels around another object (like the sun). This is known as one year.
The moon rotates and revolves at the same speed (it takes about a month for both). This is weird
because that means that one day on the moon takes the same amount of time as one year does! It also
means that the same side of the moon is always facing the earth.
21. How are protostars different from main sequence stars?
Protostars are baby stars. To become a main-sequence (real) star, NUCLEAR FUSION needs to be
taking place. The protostar needs to get enough heat and density for nuclear fusion to take place.
22. How does the atmosphere protect us from dangerous forms of radiation? Which forms does it protect
us from? Be able to draw a diagram explaining how this happens.
23. Why are elliptical galaxies unlikely to form new stars?
Elliptical galaxies have very little gas and dust and new stars need gas and dust to form.
24. How are apparent and absolute brightness different?
Absolute brightness is how bright an object or star really is. It does not change when an object moves.
Apparent brightness is how bright an object appears to be from the earth. This changes depending on
how far away the object is.
25. Describe how new stars form. How might supernovas and planetary nebulae contribute to new star
formation?
New stars form when gas and dust contract together because of gravity. Supernovas and planetary
nebulae both send gas and dust into space, which contributes to new star formation.
26. Explain why the Sun will have a longer life than a star like Betelgeuse. (Why do less massive stars live
longer?)
The sun will live longer than really large stars because the smaller the star, the slower the star burns
through its fuel. Big stars burn through all of their fuel quickly, which causes them to have a short life.
27. Why won’t the Sun end in a huge explosion like a supernova?
The sun does not have enough mass to end as a supernova. It will end as a white dwarf and then a black
dwarf. Only very massive stars will end as supernovas.
28. What is our energy source for the solar system?
The sun is our source of energy for the solar system. The sun gets its energy from NUCLEAR FUSION
so nuclear fusion is really our energy source, too.
29. Be able to put the planets in order by:1. Distance from the Sun 2. Planet diameter (size)
Distance from the Sun: (Closest) Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
Diameter: (Smallest) Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter
30. How are the inner and outer planets different?
The inner planets are all rocky planets and the outer planets are all made of gas. The inner planets are all
smaller than the outer planets. The inner planets have less moons than the outer planets.
31. How do gravity and inertia keep the planets in orbit? What two things affect the amount of gravity
between two objects?
Gravity helps to keep the planets from flying away from the Sun. Inertia helps to keep the planets from
getting sucked into the Sun and burned up. Together they keep the planets in orbit.
The two things that affect the gravity between objects are the mass of the objects and the distance
between the objects.