Mars is a very similar planet compared to Earth. It is possible that alien life once existed here on Mars. Mars is basically one super-hot, radioactive desert! Mars has an incredibly thin atmosphere consisting of 95.32% Carbon Dioxide, 2.7% Nitrogen and 1.6% Argon. Mars' atmosphere is 100 times thinner than Earth's. Once Mars too had a very thick atmosphere, possibly even before the Human Era, just when Earth was beginning to have life. Solar Wind, which is a stream of charged electrons and protons and alpha particles (subatomic particles which have 2 Neutrons and 2 Protons similar to a Helium-4 nucleus) emitted from the Sun's Corona due to the outward expansion of plasma which is heated till such a point that the Sun's gravity cannot hold it down, supposedly knocked down Mars' atmosphere and it's knocking down Earth's too! Solar Winds happen very often but because of the Earth's Magnetic field, we are kept safe from the harm of the Solar Winds. Sometimes though, if we recieve strong enough Solar Winds, the Magnetic field would still protect us but we would have MASSIVE power cuts around the whole world! One day on Mars is equal to 1 day, 37 mins on Earth. Mars' orbital period however, is equal to 687 days. Mars has a radius of 3389.5 kilometers from the center and its distance from the sun is 225.11 million kilometers!