- ‘Solar eclipse’ occurs when the moon comes between the earth and the sun.
- ‘Lunar eclipse’ does not occur every month because the moon’s orbit is not all the time in the same plane as the earth.
- If a solar eclipse occurs when the moon is quite far from the earth, the eclipse would likely to be annular.
- The earth is an oblate spheroid and not a perfect sphere, (This is because the earth has a rotational motion and the rotational speed increases as one goes from the Poles towards the Equator and the Equator experience greater gravitational pull from the sun).
- The total surface area of the earth is 510 million square kilometers.
- An observer at a point on the earth where only the penumbra region of moon’s shadow will move pass, will observe a partial solar eclipse.
- Seasons on earth are caused by the ‘Revolution of earth’ round the sun and its axis tilted at 66½.
- Days and nights are caused by the ‘Rotation of the earth’ on its axis.
- “Tides” are the highest when the sun, moon and earth are in line.
- One degree of circumference of earth measures (approx.) 111 km.