Physics & Astronomy
biosphere
91%
mars
68%
methane
52%
sampling
48%
carbon isotopes
22%
planetary surfaces
21%
activity (biology)
18%
refueling
18%
hydrogen isotopes
18%
carbonates
16%
reaction products
16%
sulfides
15%
solar system
14%
atmospheres
10%
hydrogen
8%
Earth & Environmental Sciences
serpentinite
67%
biosphere
57%
Mars
53%
methane
43%
sampling
32%
planetary surface
15%
Martian atmosphere
15%
hydrogen isotope
14%
geological record
13%
biological activity
12%
solar system
12%
carbon isotope
10%
hydrogen
8%
sulfide
8%
carbonate
7%
product
5%
test
4%
Agriculture & Biology
serpentinite
100%
biosphere
69%
methane
56%
hydrogen
21%
sampling
20%
carbon isotopes
13%
carbonates
13%
sulfides
12%
isotopes
11%
bioactive properties
9%
testing
4%