The view from Earth:

• A small world with 2 tiny satellites, Phobos and Deimos
• Polar caps of CO₂ and H₂O ices which expand and contract with the Martian seasons
• A thin, CO₂ atmosphere which hosts clouds and dust storms

Even before spacecraft landed on Mars, evidence suggested NO life:

• The atmospheric pressure is too low (0.007 Earth's) for liquid water to exist (water sublimates from solid to gas).
• Typical temperatures vary from 70 to -130 F each day.
• No large scale ozone layer to protect life from Sun's UV radiation.