|
|
|
|
|
Basic Information |
|
|
|
|
|
|
|
|
|
|
|
|
|
Physical Environment > Molecules |
This site tells the story of the history of the universe. Click Earlier and Later to follow the story. Note: Many facts have been simplified to make them easier to understand. |
|
Molecules are groups of atoms held together with covalent bonds. Molecules play a major part in this story.
The first molecules were formed in space. Some atoms which came out of a supernova were too light, and so moved too fast, to glue together with ionic bonds. They traveled out of the star until they were cool enough to attach to a dust grain. There these light atoms met and join together with a new type of bond called a covalent bond. Molecules are the building blocks of life, made mostly of the atoms hydrogen, oxygen, nitrogen and carbon. The shell model of the atom explains what molecules can be formed by which atoms. In molecular clouds in the Galaxy we can identify many of the molecules which life uses: methane, ammonia, water and formaldehyde have been identified. Amino acids, purines, and pyrimidines are possibly out there too, all forming on dust grains and eventually getting frozen into comets. This means that the raw materials of life are common in the Universe. Is life common too? For the background on how molecules were discovered, click here. |
|
| Like this web site? Buy the book! |
Physical Environment > Molecules |
|
|
Basic Information |
|
|
|
|
|
|
|
|
|
|
|
|
|
