Question

goal 1 astronomy/earth in space unit
questions

1. distinguish between rotation and revolution.
2. what does rotation cause?
3. what do revolution plus axial tilt cause?
4. how does solar energy travel to earth?
5. what is the lowest energy em radiation? what is the highest energy em radiation?
6. why is solar energy important to us here on earth?
7. distinguish between high and low tides. how often do they occur?
8. what causes all of the tides?
9. what sun-earth-moon alignment causes spring tides?
10. what sun-earth-moon alignment causes neap tides?
11. how often do spring and neap tides occur?
12. where is the earth in the milky way galaxy?
13. describe what causes the summer to be hotter than winter even though we are closer to the sun in our winter?
14. why are seasons opposite in the southern and northern hemispheres?
15. kepler’s first law states that planets orbit the sun in the shape of an
16. if an ellipse’ shape is close to 1, its

Answer:

To answer these questions, we'll address each one briefly:

1. Distinguish between rotation and revolution

• Rotation: A celestial body spins on its own axis (e.g., Earth rotating on its axis, causing day/night).
• Revolution: A celestial body orbits another (e.g., Earth revolving around the Sun, causing a year).

2. What does rotation cause?

Earth’s rotation causes:

• Day and night (as different parts face the Sun).
• The Coriolis effect (affecting wind/current directions).

3. What do revolution plus axial tilt cause?

Earth’s revolution (around the Sun) + axial tilt (≈23.5°) cause:

• Seasons (variations in sunlight intensity and duration by hemisphere).

4. How does solar energy travel to Earth?

Solar energy travels to Earth via electromagnetic radiation (specifically, mostly visible light, infrared, and ultraviolet), moving through space as photons (radiant energy).

5. Lowest and highest energy EM radiation?

• Lowest energy: Radio waves (longest wavelength, lowest frequency).
• Highest energy: Gamma rays (shortest wavelength, highest frequency).

6. Why is solar energy important to Earth?

Solar energy drives:

• Photosynthesis (supporting life).
• Weather/climate systems (via heating the atmosphere/oceans).
• Provides light/heat for ecosystems and human activities (e.g., solar power).

7. Distinguish high and low tides; how often?

• High tide: Water level rises (highest point), caused by gravitational pull (Moon, Sun).
• Low tide: Water level falls (lowest point), between two high tides.
• Frequency: High/low tides occur ~every 12 hours 25 minutes (semidiurnal tides, most common).

8. What causes ALL tides?

Tides are caused by the gravitational pull of the Moon (primary) and Sun (secondary) on Earth’s oceans, combined with Earth’s rotation.

9. Sun-Earth-Moon alignment for Spring tides?

Spring tides occur when the Sun, Earth, and Moon are aligned (full moon or new moon). The Sun and Moon’s gravitational pulls combine, creating higher high tides and lower low tides.

10. Sun-Earth-Moon alignment for Neap tides?

Neap tides occur when the Sun, Earth, and Moon form a right angle (first or third quarter moon). The Sun and Moon’s gravitational pulls partially cancel, creating lower high tides and higher low tides.

11. How often do spring/neap tides occur?

Spring and neap tides occur every 2 weeks (≈14 days): Spring tides at full/new moons, neap tides at quarter moons.

12. Where is Earth in the Milky Way?

Earth (and the Sun) lies in the Orion Arm (a minor spiral arm) of the Milky Way galaxy, about 26,000 light - years from the galactic center.

13. What causes summer to be hotter than winter (despite closer Sun in winter)?

Summer is hotter because of axial tilt: In summer, a hemisphere (e.g., Northern) is tilted toward the Sun, so sunlight hits at a steeper angle (more direct, concentrated energy) and has longer days. Earth is actually farther from the Sun in Northern Hemisphere summer (perihelion is in January, aphelion in July).

14. Why are seasons opposite in Southern and Northern Hemispheres?

Seasons are opposite because when one hemisphere (e.g., Northern) is tilted toward the Sun (summer), the other (Southern) is tilted away from the Sun (winter), and vice versa.

15. Kepler’s first law: Planet orbits?

Kepler’s first law states planets orbit the Sun in the shape of an ellipse, with the Sun at one of the two foci.

16. If an ellipse’s shape is close to 1 (eccentricity)?

Eccentricity (\(e\)) of an ellipse is \(e=\frac{c}{a}\) (where \(c\) = distance from center to focus, \(a\) = semi - major axis). If \(e\) is close to 1, the ellipse is very stretched (elongated) (nearly a parabola); if \(e = 0\), it’s a circle.