1. Unit E – Space Exploration
Lesson 4-7 (sec 3.3)
Using Technology to Interpret Space

2. A. Triangulation is based on the geometry of a triangle triangulation
uses to determine the
2 angles and a baseline
distance to an object
baseline
slide 1 of 6

3. B. Parallax
is the
apparent shift in position of an object (eg. star) when viewed from two different places
parallax
parallax is used to
determine the angles for triangulation
the is used as the and the measurements are taken
diameter of the Earth’s orbit
baseline
6 months apart
slide 2 of 6

4. C. Star Composition separate colours in prisms visible light
separate the called a
spectroscopes
light from stars into colours and bands
spectrum
each creates
its own unique spectrum
element
the is compared to the to determine the
spectrum of a star
spectra of known elements
star’s composition
slide 3 of 6

5. Absorption Spectrum of Hydrogen
slide 4 of 6

6. D. Star Motion
the is an
apparent change in frequency of waves (sound, light) due to the movement of the source
Doppler effect
changes in can be used to determine
light waves
how fast and in what direction a star or galaxy is moving
slide 5 of 6

7. when a star is moving from earth, the spectrum is as wavelengths away
red-shifted
stretch out
when a star is moving the earth, the spectrum is as wavelengths
towards
blue-shifted
compress
distant galaxies show a
red-shift ….means universe is expanding
slide 6 of 6

8. Assignment
Worksheet 8