Habitability Flashcards
1
Q
Habitable Zone
A
- where liquid water can be stabilized
- defined as circumstellar region in which terrestrial mass planet with a favourable CO2 - H2O-N2 atmosphere
- includes: mercury, venus, earth, mars
2
Q
Limits of Life (theoretical)
A
Temperature: -15 to +122 degrees C
- above this proteins/DNA denature
- below this: mcirobes struggle to reproduce
Pressure: vacuum to >1000 atm
- highest: 130 mpc
Salinity: almost all
- salinity stabilisation
- adaption: halophile: Na/K-ATPase, enzyme push Na and K in and out of cell 3 Na and K in and out of cell 3 Na in -2 K out
- highest 37% NaCl
Low Metals, Radiation, and pH
- no life above pH 11
- radiation can break apart ice/water in oxidants
3
Q
CHNOPS
A
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, Sulphur
4
Q
Carbon
A
- backbone to all biomolecules
- forms stable bonds with CHNOPS
- doesn’t require lots of energy to break bonds apart
- breaking it down allows it to form more complex molecules - diversity
5
Q
CHNOPS are volatile
A
- volatiles: chemical elements and compounds with low boiling pt
- found in planet’s moon crust or atmosphere
6
Q
Habitability OVERALL
A
- water –> solvent of life
- CHNOPS
- energy source (photo-chem)
