In the vast cosmos, stars and planets play a fascinating role in revealing the mysteries of their composition. How do we come to know the elements that make up these celestial bodies? The answer lies in spectroscopy, an amazing tool that allows us to unravel cosmic secrets.
When we look at a star or a planet, we are actually admiring the light they emit. This light contains valuable information about the composition of these celestial objects. Spectroscopy breaks this light down into its colour components, much like a prism would, revealing unique spectral lines that act as chemical fingerprints.
Each chemical element leaves its unique mark on the light spectrum, each with its own distinctive color. By analyzing these spectral lines, astronomers can identify the elements present in stars and planets. For example, hydrogen produces distinctive spectral lines in the red, while helium leaves its signature in the green. When we study planets in our solar system, we find that they also emit light, although they do not generate it themselves. This reflected light offers us clues about the composition of the planetary atmosphere and surface. For example, the presence of water on a planet can be revealed through specific spectral lines.
Now that we understand why scientists are giving us information about the possible presence of life, water, metals or precious stones on a planet, let's dive into the immense possibilities and new questions that arise every day with the images captured by all the telescopes of space agencies and astronomers.
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