Satellite detects large mass of water in Mars canyon
The FREND instrument searches for neutrons to map hydrogen content in the Martian soil.FREND revealed an area with an unusually large amount of hydrogen in the colossal Valles Marineris canyon system: assuming the hydrogen we see is bound into water molecules, as much as 40% of the near-surface material in this region appears to be water.How confident are we that hydrogen detected really is water?