1. What is orbital plane ?
2. What do you understand by circle of illumination ?
3. What would happen if the earth did not rotate ?
4. What is a leap year?
5. Why there is change in seasons?
6. What is elliptical orbit?
Answers
1.The orbital plane of a revolving body is the geometric plane in which its orbit lies. Three non-collinear points in space suffice to determine an orbital plane.
2.Circle of illumination is an imaginary line that separates light from darkness and day from night. Earth's axis refers to an imaginary line going through the center of the earth from top to bottom.
3.If the Earth stopped spinning suddenly, the atmosphere would still be in motion with the Earth's original 1100 mile per hour rotation speed at the equator. All of the land masses would be scoured clean of anything not attached to bedrock.
4.one year in every four, in which February has 29 days instead of 28.
5.Some assume our planet's changing distance from the sun causes the change in the seasons. That's logical, but not the case, for Earth. Instead, Earth has seasons because our planet's axis of rotation is tilted at an angle of 23.5 degrees relative to our orbital plane – the plane of Earth's orbit around the sun.
6.In astrodynamics or celestial mechanics, an elliptic orbit or elliptical orbit is a Kepler orbit with an eccentricity of less than 1; this includes the special case of a circular orbit, with eccentricity equal to 0. In a stricter sense, it is a Kepler orbit with the eccentricity greater than 0 and less than 1.