Jupiter
Jupiter is composed of hydrogen and a quarter of helium. It is the largest planet in the solar system and has a diameter of 142,984 km. The average density of Jupiter is 1.326 g/cm3. The Jupiter clouds are composed of ammonia crystals. We all know the famous Great Red Spot on Jupiter, it is an anticyclonic storm which larger Earth.
The latest image of Jupiter captured by the Hubble Telescope on 25th August 2020 clearly shows a bright, white stretched-out storm running around the planet at a speed of 560 kilometers per hour. There is a significant decrease in the size of the spot over the year since its discovery.
According to the late 1800s, the approximate size of the spot was 41,000 km and by 2015 the storm measures approximately 16,500 km and is decreasing about 930 km per year. According to researchers the Great Red Spot now measures about 15,771 km, it is so enormous that three Earths could fit in it. The storm is downsizing but the reason behind it is a real mystery.
Europa
On the left, you can see the moon Europa. Europa is the sixth-largest moon and is the fifteenth largest object in our solar system. It is made of silicate rock and icy crust. The surface temperature at the equator is -160o C and at the poles it is -220o C. Europa is smaller than Earth’s moon and has a thin atmosphere that is composed of oxygen. While the surface of Europa is smooth and solid, the surface of Earth’s Moon is bumpy. The Hubble Telescope also detected aqueous vapor on Europa.