SNC1D – Chapter 9.1
Name: __________________
Date: __________________
SNC1D Questions
Use the words from the word bank below to fill in the banks. Words can be used more than once.
Geocentric Model
In the ____________ model, the Earth sat at the ________ of the universe. _____________ was one of the first
people to describe in detail a geocentric ( ____________ ) model to explain planetary motion. Some
observations of planetary motion were still puzzling. For example, Mars, ______________, and
______________ appeared to loop backwards for a few months in their _________ across the sky. This
apparent reversal of the planets’ path relative to the starry backdrop is called ____________________.
Heliocentric Model
In the _____________ model, each planet orbits the Sun at a different distance. A planet’s distance from the
Sun is called the planet’s ________________. The shorter the _____________, the _________ the planet
moves in its orbit. Therefore, Earth, which is closer to the Sun than Mars is, orbits the Sun more quickly than
Mars does. This occurs not just because the orbit of Earth is ____________ than the orbit of Mars. Earth is also
moving faster than Mars. In turn, Mars is moving faster than ____________, the next planet out from the Sun.
Solstices
In the ___________ hemisphere, the __________ solstice, occurring near ____________, marks the longest
period of daylight in the year and represents the start of ___________. The ____________ solstice, occurring
near ________________, marks the shortest day of the year and represents the start of ____________. In the
_____________ hemisphere, the solstices are reversed: the summer solstice is near _____________, and the
winter solstice is near _________.
Equinoxes
An ____________ is a day when the hours of daylight and the hours of night are of __________ length. The
___________, or spring, equinox occurs about __________. The ____________, or autumn, equinox occurs
about ________________.
Elliptical Orbits
Using detailed observations of the movement of the ___________, Kepler discovered that the ___________ of
the planets were ___________ and not circles. An ___________ is somewhat like a slightly _____________
circle.
distance
centre
Geocentric
faster
winter
northern
Jupiter
autumnal
Aristotle
orbital
radius
ellipse
equinox
planets
orbit
June 21st
ellipses
December
21st
Saturn
summer
Earthcentered
southern
September
22nd
Heliocentri
c
shorter
retrograde
motion
equal
flattened
March 21st
vernal
SNC1D – Chapter 9.1
Name: __________________
Date: __________________
Questions
1. What does NASA stand for? _______________________________________
2. What probe is more than 1000 times further than the Sun compared to Earth? ________________
3. Name the four space probes sent from the years between 1972 and 1977. __________________
______________________________________________________________________________
4. Which of the space probes is the furthest away? _______________________________________
5. What 2 Latin words make up solstice? ______________________________________________
6. What 2 Latin words make up equinox? ______________________________________________
7. What is the difference between a geocentric model and a heliocentric model? _______________
______________________________________________________________________________
8. Does Saturn orbit faster than Mars? Explain. __________________________________________
______________________________________________________________________________
9. How does a sundial work? _______________________________________________________
______________________________________________________________________________
10. Describe the differences between refracting telescopes and reflecting telescopes. _____________
______________________________________________________________________________
Which one is better to use? Explain. _______________________________________________
_____________________________________________________________________________
11. What are the two types of optical telescopes used today? (The answer is not refracting/reflecting)
______________________________________________________________________________
12. What type of telescope is the MOST telescope? _______________________________________
13. What is the name of the telescope that will replace the Hubble Space Telescope, and what year will it replace it?
_______________________________________________________________
14. What are radio telescopes? ________________________________________________________
______________________________________________________________________________
15. In what ways is the radio telescope better than optical telescopes? _________________________
______________________________________________________________________________
16. How did the radio telescopes help establish the Big Bang Theory? ________________________
______________________________________________________________________________