Color is essential to telling planets’ and stars’ stories. By measuring the exact color of celestial bodies, scientists can learn about the age, chemical composition and temperature of these forms without traveling hundreds of thousands of miles. Spectrophotometers allow scientists to accurately and objectively measure the color of astronomical bodies no matter their distance, so we can learn more about the galaxy we inhabit.
What Colors Are in Space?
Space has a great spectrum of colors regarding celestial bodies, and celestial bodies are typically assorted into a spectral class according to their hue. Celestial bodies go through phases of spectral evolution where they behave similarly to iron heated in a fire. Throughout their evolutionary phases, they will shift from red to orange, yellow, white, or blue as they reach their hottest phases. Depending on trace amounts of elements — aside from hydrogen and helium — stars may appear in cooler secondary colors like purple and green.
Stars can exhibit the following colors, in order from hottest to coldest:
- O: Blue
- B: Blue/White
- A: White
- F: White/Yellow
- G: Yellow
- K: Orange
- M: Orange/Red
Around 88% of all stars in our universe are of the K and M variety, while G stars like the sun make up only 8% of celestial bodies. But while most of the universe may be orange and red, it’s also home to impressive blues, greens, purples, reds and whites.
What Is Astronomical Spectroscopy?
Astronomical spectroscopy refers to the practice of determining the properties of stars by measuring their electromagnetic wavelengths. By closely examining the electromagnetic wavelengths of celestial bodies, scientists can study the percentage of helium, hydrogen and trace elements in a star, plus its age and spectral evolution phase. Astronomical spectroscopy often uses Planck’s curve to determine a star’s peak wavelength from hundreds of thousands of miles away.
