It has a diameter of 3475 km and its circumference is 10864 km while its orbit is elliptical.
The maximum distance (apogee) of the moon from the earth is 4, 06,000 km and the minimum distance (perigee) is 3, 64,000 km.
It takes 27 days, 7 hours and 43 minutes to rotate on its axis (this period of about 27 ½ days is called the sidereal month) and approximately the same period of time it takes to revolve around the earth. The moon’s period of revolution with reference to the sun is about 29.53 days (29 days, 12 hours, 44 minutes and 2.8 seconds). This period is called a syndic month.
Only 59 per cent of the total surface of the moon is visible from the patches are low lying plains.
The bright part of the moon is full of mountains whereas the dark patches are low lying plains.
‘Sea of tranquility’, made of the plain of dust particles, is on the rear side of the moon, which always remains dark.
The highest mountain on the moon is liebuity mountain, which is 10,660 meter high.
The moon has no atmosphere, no twilight and no sound.
The temperature during daytime is about 100°C and during night it drops down to about -180°C.
The light from the moon takes 1.3 seconds to reach the earth.
The size of the Moon is one-forth (1/4th) size of the Earth.
Gravitational pull of Moon is one-sixth (1/6th) that of the Earth.
Mainly silicon, iron, magnesium etc. elements are found on the Moon’s surface.
The study of the Moon is called “Selenology”.
Moon is also known as the fossil planet.
Jupiter is the largest planet of the Solar System.
Jupiter is also known as winter planet as its average temperature is very low (-148°C).
Saturn is the second largest planet in the Solar System.
Saturn has bright concentric rings which are made up of ice and ice-covered dust particles which revolve around it.
Titan, the satellite of Saturn, is the largest satellite in the Solar System.
Uranus is about four times the size of the Earth. This planet appears greenish in colour because of methane gas present in its atmosphere.
Uranus was discovered in 1781 by Sir William Hersiel.
Uranus is the 7th planet to have been discovered by the use of a telescope.
Uranus is the third biggest planet of the Solar System.
Uranus is extremely cold, having surface temperature -190°C.
Uranus is surrounded by 5 rings namely – alpha, beta, gamma, delta and epsilon.
Uranus rotates from east to west on its axis, which is opposite to other planets.
The axis of Uranus has large inclination so that it appears to be lying down, hence it bears the name “ A Planet on its Side”
Neptune is the 8th planet of the Solar System.
The temperature on the surface of Neptune remains low.
Neptune is very similar to Uranus and can be considered as its twin.
Neptune is surrounded by methane rings of sub zero temperature.