According to IAU, a planet is a body that revolves around the sun without being another object’s satellite. The body should not be big enough to start nuclear fusion like a star and should have a clear orbiting pathway without any debris or asteroids lingering around. Pluto got re-classified as a dwarf planet because it is small in size, and there is much debris in its orbiting pathway. Frequently Mercury, Venus, Earth, and Mars are called terrestrial planets because of their rocky structure.
Mercury is a minor planet and takes 88 days to complete an orbit. Since its closest to the sun, it experiences exponential changes in day and night temperatures. During the day, the temperature goes as high as 450C, and at night it drops to -180C. Mercury’s atmosphere is made of oxygen, hydrogen, helium, and potassium. Recently scientists discovered frozen organic compounds and ice at the planet’s north pole, which changes scientist’s understanding of its surface composition.
Venus’s surface has many mountains and volcanoes. It contains sulphuric acid clouds makes its atmosphere toxic and concentrated. Its surface temperature is scorching at 465C, and the pressure could crush you. Venus spins from east to west, unlike other planets. There are many UFO reports which were from Venus.
It’s the only planet that harbours life since its two-thirds is covered with ocean and its atmosphere is rich in nitrogen and oxygen.
Its surface is like a cold desert covered with dust. This dust is made of iron oxides which give the planet a red hue. Mars is the most explored planet because, according to scientific evidence, Mars was a wetter and warmer planet billions of years ago, which could have harboured life. Recently scientists have found evidence of a water body underneath the southern’s pole which blooms the hope once more.
It is the most massive planet and a giant gas world. The different types of trace gases give the swirling clouds a colourful hue. A giant storm known as the Great Red Spot has been raging in Jupiter for the last 150 years with 400 mph and 10,000 miles wide. It also contains 75 moons.
It is known for its rings. These rings’ primary elements are ice and rock, and their atmosphere primarily consists of hydrogen and helium. It also consists of several moons.
Its cloud is made from hydrogen sulfide, which gives a foul smell. It rotates from east to west, similar to Venus. It is called an oddball because its equator is at right angles to its orbit. Scientists believe a massive object must have collided with Uranus billions of years ago to give that tilt. This tilt causes extreme weather to last more than 20 years. The methane on the surface gives the planet’s blue-green tint.
It is mainly known for its solid supersonic winds. It is the first planet found out by using maths. It is 17 times as huge as Earth, with a rocky core and cold surface.