- What did Mariner 6 and 7 measure about the composition and pressure of the Martian atmosphere?
- How did Mariner 6 and 7's findings build on what Mariner 4 discovered in 1965?
Martian Water and Climate History
Evidence for water and past climate on Mars.
- What did Viking 2 photograph at Utopia Planitia that Viking 1 could not, given its more northern landing site?
- Why was Viking 2's seismometer unable to produce useful data about marsquakes?
- How long did it take before scientists got a genuine Martian seismic record after Viking 2's seismometer failed?
- What is the leading explanation for the labelled release experiment's positive signal if not living organisms?
- How did the meteorite ALH84001 travel from Mars to Antarctica, and when was it recovered?
- What evidence did the spacecraft's camera find for liquid water once carving gullies into Martian crater walls?
- What did the remnant magnetism in Mars's southern crust suggest about the planet's past?
- How did Mars Odyssey's gamma-ray spectrometer detect water ice beneath the Martian surface?
- How much water ice did the south polar region of Mars appear to hold?
- Why did near-surface ice make plans for future human presence on Mars more feasible?
- How did the disappearance of white material over four Martian days prove it was water ice rather than dry ice?
- What caused the 2018 dust storm to end communication with Opportunity, and why couldn't the panels recover?