NASA’s Stardust spacecraft collected samples of Comet Wild 2 and returned them to Earth. NASA scientists have been studying the samples and have discovered interesting components, or parts, of the comet that support the development of life as we know it. For the first time scientists have primitive extraterrestrial (non-Earth) materials to study.

Life on Earth is the only type of organisms that are known and are studied in detail. All life on Earth is similar in their basic structures, or building blocks. Scientists discovered the building block glycine in the comet sample. Glycine is an amino acid used in living organisms to make proteins. Amino acids are fundamental, or basic, building blocks of life. Proteins are sometimes called the workhorse molecules of life, because they are used in structures like hair and enzymes. Life uses 20 different amino acids in different combinations and arrangements to build millions of different proteins. It’s like using the 26 letters in the alphabet in different combinations to make words.

Amino acids from a comet that was made from the materials of the primitive, early solar system, indicates that the fundamental building blocks of life are prevalent in our solar system. It supports the theory, or idea, that some of the ingredients for life formed in space and were delivered to Earth long ago by meteorite and comet impacts.

The discovery that amino acids are apparently common in these ancient components of our solar system, indicate they are probably common in other solar systems in our galaxy and other galaxies throughout the universe. This new idea will influence the ongoing argument among astronomers about life in the universe. The popular theory was that life was very rare. With this new information, life in the universe may be very common.