Does life have to have a climate like Earth? Out in space somewhere, can life not exist on a frozen planet or on a sun and just evolve to be able to live in its environment?

Life exists on Planet Earth in all kinds of places that are not where you would expect life should exist. Therefore, life could exist on other planets with similar bizarre climates.

For example:

  1. Deep under the ocean there are volcanoes erupting. The water temperature is way above boiling there and yet we have found these areas teaming with life.
  2. Life has been found in bubbling hot tar.
  3. The Deinococcus is listed as the “world’s toughest bacterium” in the Guinness Book of World Records because it withstands huge amounts of radiation that no life should be able to withstand.
  4. Pitch Lake in Trinidad is 250 deep and bubbling with hydrocarbon fumes seeping from oil reserves and is full of microscopic life.
  5. Lake Untersee in Antarctica has been iced over for 100,000 years. It is here they find Stromatolites mounds built by microorganisms.
  6. Researchers found these autochthonous organisms at the bottom of a South African gold mine.

Credit. So if life can exist in all these unexpected places on Earth (and more) then there is some possibility life can exist in different environments on other planets. The problem? We just haven’t found anything yet.

What's the use of the universe if Earth is the only habitable planet?

First, we don’t know Earth is the only habitable planet. However, until we have some proof, we have no way of knowing for sure. That’s why we’re searching so hard for extraterrestrial organisms.
Second, who says the universe has to have a use? It just is. Similarly, you could say what’s the use of living if you die in the end. That kind of view doesn’t do anyone any good. Just go with it and enjoy the exploration and discovery life offers us, like whether or not life exists elsewhere in the Universe.

Why is there a stigma around attempting to discover extraterrestrial life?

There is no stigma. All of science is dedicated to discover extraterrestrial life. We would be completely excited to find even a fossil of a microbe from space because it would be the ultimate affirmation that life can evolve from matter on another world other than Earth. Our best hope at present is to find some kind of life on one of the moons of Jupiter or Saturn, or perhaps some fossils on Mars as of yet undiscovered. We are even spending billions of dollars with the SETI program to listen for radio waves from space!

However, much to the surprise and dismay of scientists, we have yet to discover anything at all.