Mars atmosphere is mostly Carbon Dioxide. The atmospheric pressure is only like 2% of Earth’s, however, so it doesn’t do that planet much good. It’s nearly a vacuum as these things go.
I am gravely concerned that both Jupiter and Saturn will also lose their ice caps, now, and Saturn will lose its ice rings. Space exploration will not be possible with Covid-19 social distancing requirements.
https://www.rt.com/news/479860-mars-polar-ice-collapse-photo/