Earth illustration. ©Pixabay/Joshart3d
Reporter: Merdeka
Merdeka.com – Many mysteries of the universe are still unsolved by scientists, one of which is related to life in this vast galaxy.
We believe that Earth is the only planet that has life, so how did life on Earth actually begin? What series of events led to the presence of birds, insects, and even humans?
Questions related to the mystery of ‘how’ about life are still many unresolved. Searching for the origins of life on Earth means asking yet another enigmatic question: How impossible is it for life to form on other planets?
Reporting from Vox.com, Thursday (23/3) Here are 3 mysteries of life that have not been solved by scientists about Earth:
Where does Earth’s water come from?
The search for why there is life on Earth begins with water. Water is the main element that forms life, no living things can survive without water.
However, based on research, the formation of the Earth was so hot that any water around the Earth would boil.
“So how did you get so much liquid on the surface of a planet that should be so hot?” asked Lydia Hallis, a planetary scientist from the University of Glasglow.
Scientists think of a possible plausible answer, was it the effect of a comet crashing into our world? or maybe water was somehow buried deep in the interior of the primordial Earth?
Hallis has traveled the world to find some of the oldest water samples on Earth, here’s what he’s learned so far.
How did water start life?
For decades, scientists have attempted to mimic the conditions of the primordial Earth. Their hope if the copy is successful is to be able to create something similar to the first cells that formed billions of years ago. From there they can gather a chronology of how life on Earth began.
In the 1950s, scientists Harold Urey and Stanley Miller demonstrated the possibility of synthesizing the amino acid glycine by mixing some of the gases believed to have filled the atmosphere billions of years ago, with heat and simulated lightning. Since then they have formed RNA molecules which are a type of DNA.
But it still doesn’t work to create life in a bottle. If the mission is successful, they may not only unravel the origin story of life on Earth, but come to surprising conclusions about how common life is in the universe.
What is life?
This question sounds trivial, even like a question for a 5th grader. But do we really know what the fundamental meaning of life is? The answer is no.
Author of Life’s Edge: The Search for What it Means to be Alive, Carl Zimmer, says “the human brain is hard-wired to recognize life, but that doesn’t really mean that we know what life is,”
For every definition of life, scientists can come up with some pretty baffling exceptions. Take NASA’s definition of life for example: “Life is a self-sustaining chemical system capable of Darwinian evolution.”
This definition excludes viruses that are considered to be unable to ‘self-defense’ and can only survive by infiltrating a host.
On the one hand, the definition of life is useful for looking for signs on other planets. But Zimmer still says it’s impossible to define life, at least not with current human knowledge.
Intern reporter: Safira Tiur Margaretha
(mdk/phase)