Why does NASA observe the sun in different colors?

In photos, the sun looks bright and white… or we might perceive it as a bit yellow because of how light is scattered in the air. But the sun has all colors of the rainbow, and white light is created by that combination.

That’s why, physics professor Dr. Christopher Baird explains, “we can see so many different colors in the natural world under the illumination of sunlight.” From the NASA Goddard video above:

“Our eyes can only see a narrow range of light known as the visible spectrum. When they combine together, they make white light. But the Sun also emits light that is invisible to the naked eye.”

Not long after it launched in February of 2010, NASA’s Solar Dynamics Observatory (SDO) enabled scientists to observe and better understand these never-explored facets of the sun. The comprehensive picture is possible because “SDO sees the sun in more than 10 distinct wavelengths of light, showing solar material at different temperatures.” From NASA in 2013:

“Different wavelengths convey information about different components of the sun’s surface and atmosphere, so scientists use them to paint a full picture of our constantly changing and varying star.”

And from the video caption:

“SDO also measures the Sun’s magnetic field and the motion of solar material at its surface, and, using a technique called helioseismology, allows scientists to probe deep into the Sun’s interior, where the Sun’s complex magnetic fields sprout from. And with more than a decade of observation under its belt, SDO has provided scientists with hundreds of millions of images of our star.”

Via NASA, click on the Goddard Media Studios image below to see these distinct wavelengths a bit larger:

“From the sun’s surface on out, the wavelengths SDO observes, measured in angstroms, are:

4500: Showing the sun’s surface or photosphere.

1700: Shows surface of the sun, as well as a layer of the sun’s atmosphere called the chromosphere, which lies just above the photosphere and is where the temperature begins rising.

1600: Shows a mixture between the upper photosphere and what’s called the transition region, a region between the chromosphere and the upper most layer of the sun’s atmosphere called the corona. The transition region is where the temperature rapidly rises.

304: This light is emitted from the chromosphere and transition region.

171: This wavelength shows the sun’s atmosphere, or corona, when it’s quiet. It also shows giant magnetic arcs known as coronal loops.

193: Shows a slightly hotter region of the corona, and also the much hotter material of a solar flare.

211: This wavelength shows hotter, magnetically active regions in the sun’s corona.

335: This wavelength also shows hotter, magnetically active regions in the corona.

94: This highlights regions of the corona during a solar flare.

131: The hottest material in a flare.”

Then watch these videos next:
• Jewel Box Sun: Invisible wavelengths of light translated into colors
• A Decade of Sun: Ten years of SDO highlights
• What is light? Royal Observatory Greenwich explains…