Is there any life in the universe, other than on earth?
|Extraterrestrial life may even be quite abundant given the myriads of planets that are out there. Life forms are always – as far as we know – based on cells. There are many clues for the creation of the essential building blocks for living cells from gases present on exoplanets. At temperatures between 0 and 400 centigrades sugar molecules can be formed through several steps.The substances from which these sugars are formed, such as formaldehyde, have been found with the ALMA (Atacama desert Radiotelescope) in interstellar space and near meteorites. At distances of thousands of lightyears or more. One of the sugars formed from formaldehyde – ribose – is the first step in the formation of RNA. In evolution on Earth, DNA has been formed from this. Other molecules such as amino acids and lipids – important for living cells – can also be formed on exoplanets and in distant celestial bodies, as a product of chemical reactions. These substances have been measured deep in the universe with radio telescopes as well. That means the creation of living cells does not require a miracle. It may not even be exceptional, even though it has taken millions of years on earth for cells to develop >>_ Read more
Life on exoplanets may be formed when certain chemical elements are present. The elements that form life are mainly Carbon, Hydrogen, Oxygen, Nitrogen and Phosphorus. In addition, elements like Magnesium, Calcium, Sulphur, Sodium, Potassium, Iron, Copper and some other elements are needed for plants and /or higher organismsMany molecules that are essential for life exist only below 60 centigrades. On the other hand, at low temperatures life processes slow down. Therefore, most organisms are in reality limited to temperatures between roughly 0 and 40 centigrades. In living cells, a temperature around 30 centrigrades is often optimal for the combination of molecular stability, transport rate by diffusion and reaction kinetics. The size of cells highly contributes to finding the optimal proces conditions, given the
Are there higher life forms on exoplanets?
A Planet quick-scan will reveal its surface radiation from the dominant star, its atmosphere composition and density, an assessment of the presence of liquid water, and a weather and climate assessment. Life prerequisite conditions can then be evaluated.
Evolution may have occurred – or may occur in any future – on planets with special environments and special circumstances. The mechanisms of evolution from simple cells are complex. READ MORE
Are there life forms based on Silicon?
No, even though Silicon has chemical similarities with Carbon, it cannot form all the complex molecules needed for life.The process that basically creates life’s molecules from the ‘stable’ molecules water and carbondioxide, is well-known. It is called photosynthesis. Visible light that comes from a star can be caught in an organism that converts carbondioxide and water to sugar-like molecules, emitting pure oxygen.Another essential process for life is the conversion of nitrogen gas to amino groups in molecules that are called amino acids. The sugars, polysaccharides, lipids, amino-acid based peptides and water are the building blocks of living cells. And when life ends, it returns – to the environment – the three basic components: water, nitrogen and carbondioxide (and the other elements, like Calcium in the form of its carbonates).