Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2023 June 11
A rainbow of the Sun's colours is shown from deep red on the upper left
to deep blue on the lower right. Some horizontal lines have gaps
that appear dark where some colours are missing. 
the image.
Please see the explanation for more detailed information.

The Sun and Its Missing Colours
Image Credit: Nigel Sharp (NSF), FTS, NSO, KPNO, AURA, NSF

Explanation: Here are all the visible colours of the Sun, produced by passing the Sun's light through a prism-like device. The spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our white-appearing Sun emits light of nearly every colour, it appears brightest in yellow-green light. The dark patches in the featured spectrum arise from gas at or above the Sun's surface absorbing sunlight emitted below. Since different types of gas absorb different colours of light, it is possible to determine what gasses compose the Sun. Helium, for example, was first discovered in 1868 on a solar spectrum and only later found here on Earth. Today, the majority of spectral absorption lines have been identified - but not all.

Tomorrow's picture: largest satellites


< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
NASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC,
NASA Science Activation
& Michigan Tech. U.