Biosignatures Flashcards
What are biosignatures?
Any characteristic element, molecule, substance or feature that can be used as evidence of past or present life and is distinct from abiogenic process
What is an organic compound?
Any molecule that has carbon-carbon or carbon-hydrogen bonds
How do organic compounds aid the search for life?
They are either directly produced by microbes or by the products of these molecules
Types of biosignatures
- macro structures/textures
- organics
- minerals
- chemistry
- isotopes
When was the viking mission launched?
1976
What were the three experiments that the viking lander carried out?
- labelled release
- gas exchange
- pyrolytic release
Describe the labelled release
added nutrients to Martain soil, used carbon 14, bio material would use this to metabolise and produce waste gas - POSITIVE RESULT
Describe the gas exchange
added nutrients but not carbon 14 - NEGATIVE
Describe the pyrolytic release
Same as the labelled release but the soil was baked - NEGATIVE
What happened after the 3 viking experiments ?
GC-MS was used to look for organics - NEGATIVE
Why did the viking results happen ?
Phoenix mission discovered presence of perchlorate which is a salt that when heated breaks down organics and releases co2