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Astronomy – define:
The Universe – define:
The Known Universe – define:
What is in the known universe?
Space –
Galaxies –
Star Clusters –
Star Systems –
Stars –
Nebulae –
Black “holes” –
Galaxies, Star Clusters, Star Systems
What is a Galaxy?
Three main types
1.
2.
3.
Our Galaxy –
Type?
Size and number of stars?
Star Clusters– Two major kinds
1.
2.
Star systems – Two major kinds
1.
2.
Constellations: define
Zodiac Constellations:
“Life” of a star – Stages of development
1. ________________________ - stars begin as a large dust and gas cloud in space.
2. ________________________ - occurs nearby and shoots matter and energy into the
nebula, “seeds” it with elements not originally present and causes it to spin
3. ________________________ - because of gravity the nebula collapses inward. (In
the case of our Sun approximately 98% of the matter in the nebula became the star). This
collapsing mass is under great pressure and heats up and is called a _____________.
(This kind of temperature change is called an ___________ ____________ ______)
4. ________________________ - if the core of this collapsing mass gets hot enough and
it is now a star.
5. Eventually, ________________________ - the star will collapse, heat up again.
6. ________________________ - when it reaches the next critical temperature
7. Eventually,_________________________ - The star will again collapse. It is at this
point that there is a difference in what happens to different size stars.
Divergence: What happens next depends on the overall mass of the star:
First we will deal with the small to medium stars (like the Sun)
8. ___________________________ - No more fusion.
9. ____________________________ - Expands to a Red Giant. (The Sun will at this
time engulf the planets Mercury, Venus, Earth, and probably Mars)
10. ___________________________ - outer ring of gases continues to expand
11. ____________________________ - __________ is formed (glowing mass about the
size of the Earth), but with no further energy source will eventually burn out to a
________________________.
Reminder: The stages a star goes through depend on its ______________.
Giants and Supergiants
8. _____________________ - heats up enough to begin the next fusion step
9. _______________________ - for an unknown reason the core then continues
to heat up
10. ______________________ - Energy wave from the core of the very massive
star shoots outward overcoming gravity; the star explodes
Giants
11. ______________________ - core collapses producing the smallest most
dense star; densities can be 100,000,000 tons/cm3. [Three times the mass of the Sun in a
diameter of 25 km (15 mi.)]
Another divergence:
Supergiants
11. _______________________ - collapses into a structure so dense that it has so
much gravity that nothing escapes it, not even visible light.
- not possible to detect directly because no energy is given off, need to look at
surrounding area to find another star caught in its gravity and see what it is doing to that
companion star
SOLAR SYSTEM NOTES
1. How do scientists believe our solar system formed?
2. What does the term planet mean?
3. Why is Pluto no longer considered a planet? What are some of the other structures
now characterized with it?
4. What is the measurement unit called an AU?
5. Explain what happens to the period of revolution of the planets as we move outward
in the solar system.
6. What is a major difference between the Inner Planets and the Outer Planets?
7. Why is Mars red?
8. Why is Venus even hotter than Mercury?
9. Jupiter, Saturn, Uranus, and Neptune together are called the
_________________________.
10. Which planets have rings?
11. What number planet from the Sun is Uranus?
12. Which planets in our solar system have retrograde rotations? What does retrograde
mean?
13. Which two planets do not have moons?
14. What are the names of the four Galilean moons of Jupiter? Which one of these is the
largest moon in our solar system?
15. What is the name of Pluto’s moon?
16. What are the names of Mars’ two small moons?
17. What are the two proper names for the Earth’s moon?
18. Why do we always see the same side of our moon?
19. Where is the Keiper Belt? What solar system objects probably originate there?
20. What is the coma of a comet?
21. Why does the tail of a comet always point away from the Sun?
22. What does the term “Asteroid” actually mean? Where in our Solar System would you
find the asteroid belt?
23. Earth Moon Sun relationships
Eclipses
Solar –
Moon’s shadow has two parts:
1. Umbra –
2. Penumbra –
Lunar –
Earth’s shadow also has the same two parts as the Moon’s shadow does
(Umbra and Penumbra)
Phases of the Moon
Tides Primary cause Secondary causes Tides cycle timing –
Spring tide –
Neap tide -
The “Reasons for the Seasons” – (review)
2 Major reasons are both related to the ____
___ ____ ____________ ________ and the ___________ _____________ around the
Sun.
1. _______________________ - (review)
If the Northern Hemisphere is tilted toward the Sun, we receive ___________________
_____________. This causes us to heat up more. If the Northern Hemisphere is tilted
away from the Sun, we receive __________
____________________. This doesn’t allow us to heat up as much.
2. ____________________________ What is happening to the length of daylight at this time of the year? (diagram why)
After the end of December the day light will __________ __________. This will
continue until the end of June. At that time we will again start to get ________
__________.
Important Seasonal Dates
1. June 21st – ish –
2. September 21st – ish –
3. December 21st – ish –
4. March 21st – ish -