Asteroid Impacts and Life on Earth

Click For Summary
SUMMARY

Asteroids played a crucial role in delivering over 1018 metric tons of water and organic compounds to Earth, which are essential for the emergence of life through abiogenesis. Key processes include the formation of organic molecules from inorganic materials and the potential development of self-replicating systems in prebiotic environments. The discussion highlights the significance of water's polar properties in facilitating chemical reactions and the formation of proteins and cell membranes, which are fundamental to all known life. Additionally, the Murchison meteorite is noted for containing pre-formed amino acids and organic compounds that contribute to our understanding of life's origins.

PREREQUISITES
  • Understanding of abiogenesis and its mechanisms
  • Familiarity with organic chemistry, particularly the formation of organic molecules
  • Knowledge of protein synthesis and the role of tRNA
  • Awareness of the significance of meteorites in delivering organic materials to Earth
NEXT STEPS
  • Research the role of hydrothermal vents in the origin of life
  • Explore the properties of water and its impact on biochemical reactions
  • Investigate the Murchison meteorite and its contributions to astrobiology
  • Study the mechanisms of RNA self-replication and its implications for early life forms
USEFUL FOR

Astrobiologists, chemists, evolutionary biologists, and anyone interested in the origins of life on Earth and the role of extraterrestrial materials in biochemical processes.

Anonymous 69
Messages
4
Reaction score
1
Scientists say when asteroids showered on Earth they were the ones who brought water to Earth which started life. But how did few molecules of water started life on earth?
 
Biology news on Phys.org
Nobody knows.
It's called abiogenesis.
Here is a link to the wiki page: https://en.wikipedia.org/wiki/Abiogenesis

One presumed step in the process is the creation of organic molecules from inorganic materials: rocks, water, and gases.

Perhaps the real trick is to go from there to an organic molecule (or system) that can self-replicate and mutate in any natural prebiotic environment. I don't believe anyone has discovered that trick.
 
  • Like
Likes   Reactions: YoungPhysicist
 
  • Like
Likes   Reactions: pinball1970 and BillTre
Anonymous 69 said:
Scientists say when asteroids showered on Earth they were the ones who brought water to Earth which started life. But how did few molecules of water started life on earth?

They didn't bring a "few" molecules, they brought more than 1018 metric tons. The reason this is important to life is because water forms a medium in which an enormous range of chemicals can mix together, which in turn allows thousands of different chemical reactions to occur. In addition, water's polar properties (meaning one side of it is charged negative and the other side is positive) cause the folding of certain molecules we call proteins and provides a mechanism for the construction of cell membranes. All of these things are requirements for all known life.
 
  • Like
Likes   Reactions: pinball1970, russ_watters, jim mcnamara and 1 other person
I wish to offer speculations that

1) the first cells had no lipid membranes, but only proteinaceous walls vaguely like the outer layers of prokaryotes and viruses... This hypothesis affords you the option of getting started with only RNA and protein.

2) TRNA. Binds amino acids. On to the rybose opposite the nucleobase [2a]. This suggests that an early RNA strand could have used ribose as the translator intermediate with all of the nucleobases on one side of the backbone, templating for all of the amino acids on the other. Indeed [2b], only the pyrimidines U,C have known prebiotic precursors. So possibly the first RNA strands were purely Pyramidine based. And so had no self binding. Or double Helix forming structural. Capabilities. A pure pyrimidine RNA strand would remain single stranded And linear, an ideal template for amino acid. Linkage.

[2a] https://www.atdbio.com/img/articles/protein-synthesis-tRNA-large.png
[2b] http://astrobiology.com/2018/12/life-has-a-new-ingredient.html
 
  • Like
Likes   Reactions: pinball1970
Anonymous 69 said:
Scientists say when asteroids showered on Earth they were the ones who brought water to Earth which started life. But how did few molecules of water started life on earth?

As well as water 1000s of organics in the form of meteorites fall to Earth every year, some of these organics contain amino acids alcohols and bases already formed

This one fell 1969 and has been studied intensively since, the fragments when collect weighed over 100kg

https://en.wikipedia.org/wiki/Murchison_meteorite

I would google deep sea vents as a starting point for first proto cells

https://www.livescience.com/26173-hydrothermal-vent-life-origins.html
 
  • Like
Likes   Reactions: symbolipoint

Similar threads

Replies
4
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 14 ·
Replies
14
Views
4K
Replies
0
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K