A corona is an aura of plasma that surrounds the Sun and other stars. The Sun's corona extends millions of kilometres into outer space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph. Spectroscopy measurements indicate strong ionization in the corona and a plasma temperature in excess of 1000000 kelvin, much hotter than the surface of the Sun. Light from the corona comes from three primary sources, from the same volume of space. The K-corona is created by sunlight scattering off free electrons; Doppler broadening of the reflected photospheric absorption lines spreads them so greatly as to completely obscure them, giving the spectral appearance of a continuum with no absorption lines.

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ESA’s Solar Orbiter Observes Magnetic Switchback in Sun’s Corona

Jesuit priest Angelo Secchi pioneered astropohysics. In 1860 he was one of the first people to photograph the sun during an eclipse and proved that the sun’s corona was real and not just an optical illusion

Crowning a quest into a very well-guarded secret: Structure of the kinetochore corona finally revealed

The sun's atmosphere: Photosphere, chromosphere and corona

Spacecraft Enters the Sun’s Blistering Hot Corona for the First Time in History

My encounter with a different and deeply mysterious kind of corona

Spacecraft enters the Sun's corona for the first time in history

First Corona Lockdown Was a “Live Experiment” – Revealed Big Behavioral Gender Differences

Sounding rocket mission targets mysteries of solar corona

Scientists' 1st-ever view of sun's middle corona could sharpen space weather forecasts

Scientists' 1st-ever view of sun's middle corona could sharpen space weather forecasts

A new understanding of a mysterious part of the sun, the middle corona, are important for NOAA’s mission to forecast space weather. This study is the first to provide high-quality observations of its dynamics/solar flares.

Corona gets us tired

New corona mass test up to 100 times more sensitive than rapid antigen tests

The effects of protein corona on the interactions of AIE-visualized liposomes with ce

Mysterious heating of sun's corona powered by solar 'campfires,' study suggests

Corona Inhibitors: X-ray Screening Identifies Promising Drugs for Treatment of COVID-19

Children and Corona: More infections than reported cases during second wave in Germany

The 'great leveler' revisited: Why the Corona pandemic might boost inequality in society