Because the mass of the planet holds it down.
the gas giant planets have strong gravitational pulls that hold on to their thick atmospheres. Additionally, the high escape velocity prevents the gases from escaping into space. The cold temperatures of these planets also help in maintaining the integrity of their atmospheres.
The atmosphere is held in place by gravity. Other things being equal, the more massive the planet, the harder it is for a gas molecule to escape into space.
Space does not have an atmosphere. It is generally considered a vacuum. Planets and some moons have atmospheres.
Gravity.
Jovian planets do not have a solid surface, therefore their atmospheres are thick all the say to where their surface would be. Their atmospheres have more gasses than those surrounding terrestrial planets.
They all are. If you are thinking about those that have atmospheres, it is not much protection.
Yes they in fact do reveal some levels of the outer planets and their interior atmospheres.
Mercury's gases escaped into space once
Usually not - they would have too little mass to keep an atmosphere. However, it is conceivable that an asteroid that has sufficient mass and is far enough from the Sun can keep an atmosphere. Some of the dwarf planets (Pluto, Ceres) have atmospheres, but these are not very significant, and tend to escape into outer space, due to the reduced gravitation.
gravity keeps the giants planet's gasas from escaping
Yes, space probes have studied the atmospheres of planets and moons in our solar system. For example, the Cassini mission observed the atmospheres of Saturn and its moons, while the Juno mission focused on studying Jupiter's atmosphere. These observations help scientists better understand the composition, structure, and dynamics of these planetary atmospheres.
Yes, there is water in outer space in the form of ice and vapor. It can be found in comets, asteroids, and even in the atmospheres of some planets and moons.