ASTR 205 Universe - The Ultimate
Frontier Quiz 1 2025 Athabasca
University
1 to 25 question solutions
1.Distance from the Sun to Pluto:
Light takes 8 minutes to reach Earth (1 AU) and 5 hours to reach
Pluto.
5 hours = 300 minutes → 3008=37.5\frac{300}{8} =
37.58300=37.5 AU.
Answer: β. 40 AU (closest to 37.5 AU).
2.Star Movement Near NCP (Northern Hemisphere):
Stars near the North Celestial Pole appear to rotate counter-
clockwise due to Earth's rotation.
Answer: α. counter-clockwise
3.Brightness Comparison (Magnitude Scale):
A difference of 2 magnitudes → 2.5122≈6.32.512^2 \approx
6.32.5122≈6.3. Star A is brighter than Star B by a factor of 6.3.
Answer: δ. 6.3 times brighter
4.Conditions for Eclipses:
Eclipses occur when the Sun is near the line of nodes and the
Moon is new or full.
Answer: ε. when the sun is near the line of nodes of the
moon and the moon is new or full
5. Solar Angle at Latitude 38°N (Winter Solstice):
Sun's declination is -23.5°. Altitude = 90°−(38°+23.5°)=28.5°90°
- (38° + 23.5°) =
28.5°90°−(38°+23.5°)=28.5°.
Answer: δ. 28.5°
, 6.Angular Diameter of a Marble (1 arcsecond):
Using D=206,265×dθD = \frac{206,265 \times d}{\
theta}D=θ206,265×d: D=206,265×0.021≈4.1 kmD = \
frac{206,265 \times 0.02}{1} \approx 4.1 \,
\text{km}D=1206,265×0.02≈4.1km.
Answer: ε. 4.1 km
7.Halley's Comet (Kepler’s 3rd Law):
P2=a3P^2 = a^3P2=a3 → 762=a376^2 = a^3762=a3 → a≈18a \
approx 18a≈18
Frontier Quiz 1 2025 Athabasca
University
1 to 25 question solutions
1.Distance from the Sun to Pluto:
Light takes 8 minutes to reach Earth (1 AU) and 5 hours to reach
Pluto.
5 hours = 300 minutes → 3008=37.5\frac{300}{8} =
37.58300=37.5 AU.
Answer: β. 40 AU (closest to 37.5 AU).
2.Star Movement Near NCP (Northern Hemisphere):
Stars near the North Celestial Pole appear to rotate counter-
clockwise due to Earth's rotation.
Answer: α. counter-clockwise
3.Brightness Comparison (Magnitude Scale):
A difference of 2 magnitudes → 2.5122≈6.32.512^2 \approx
6.32.5122≈6.3. Star A is brighter than Star B by a factor of 6.3.
Answer: δ. 6.3 times brighter
4.Conditions for Eclipses:
Eclipses occur when the Sun is near the line of nodes and the
Moon is new or full.
Answer: ε. when the sun is near the line of nodes of the
moon and the moon is new or full
5. Solar Angle at Latitude 38°N (Winter Solstice):
Sun's declination is -23.5°. Altitude = 90°−(38°+23.5°)=28.5°90°
- (38° + 23.5°) =
28.5°90°−(38°+23.5°)=28.5°.
Answer: δ. 28.5°
, 6.Angular Diameter of a Marble (1 arcsecond):
Using D=206,265×dθD = \frac{206,265 \times d}{\
theta}D=θ206,265×d: D=206,265×0.021≈4.1 kmD = \
frac{206,265 \times 0.02}{1} \approx 4.1 \,
\text{km}D=1206,265×0.02≈4.1km.
Answer: ε. 4.1 km
7.Halley's Comet (Kepler’s 3rd Law):
P2=a3P^2 = a^3P2=a3 → 762=a376^2 = a^3762=a3 → a≈18a \
approx 18a≈18
