Front

What day does the equator receive direct rays from the sun?

Back

The equator receives direct rays from the sun on September 23 and March 21.

Front

What shape has an eccentricity of zero?

Back

A circle has an eccentricity of zero.

Front

How many hours of daylight does the North Pole receive when the Sun follows path A on the winter solstice?

Back

The North Pole receives 0 hours of daylight on that day.

Front

What is the definition of eccentricity in relation to orbits?

Back

Eccentricity is a measurement of how elliptical an orbit is.

Front

What does Kepler's third law state?

Back

Kepler's third law states that a planet with a greater mean distance from the Sun will have a greater period of revolution.

Front

What are Kepler's three laws of planetary motion?

Back

1. The orbit of a planet is an ellipse with the Sun at one focus. 2. A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. 3. The square of the period of revolution of a planet is proportional to the cube of the semi-major axis of its orbit.

Front

What is the significance of the equinoxes?

Back

The equinoxes mark the points in the year when day and night are of approximately equal length, occurring around March 21 and September 23.

Front

What is the relationship between eccentricity and the shape of an orbit?

Back

Eccentricity measures how much an orbit deviates from being circular; an eccentricity of 0 is a perfect circle, while values closer to 1 indicate more elongated orbits.

Front

What is the effect of Earth's tilt on seasons?

Back

Earth's axial tilt causes different parts of the planet to receive varying amounts of sunlight throughout the year, leading to the changing seasons.

Front

What is perihelion and aphelion?

Back

Perihelion is the point in a planet's orbit where it is closest to the Sun, while aphelion is the point where it is farthest from the Sun.