What atmospheric and temperature conditions were necessary for ancient stable surface water on Mars?
Answer
An atmosphere thick enough and temperatures warm enough
Billions of years ago, Mars had an atmosphere that was sufficiently thick and warm enough to sustain stable bodies of liquid water on its surface.
#Videos
They Finally Found Liquid Water on Mars - YouTube
Related Questions
What geological formations provide evidence that liquid water once flowed freely on Mars?What atmospheric and temperature conditions were necessary for ancient stable surface water on Mars?What happens to pure liquid water on the Martian surface when atmospheric pressure drops too low?What are the most compelling features suggesting liquid moisture activity on present-day Mars slopes?If water cannot remain liquid on the surface due to cold and near-vacuum, what must the observed flowing water contain?What is the term used to describe the highly saline liquid flowing on present-day Mars?How deep are the transient liquid flows observed as RSLs?Where are the largest known reservoirs of modern Martian water currently locked up?What scientific evidence strongly suggests the existence of large, stable bodies of liquid water beneath the southern polar ice cap?What two physical factors are hypothesized to maintain the liquid state of deep underground water reservoirs?