When the Moon completely obscures the Sun on April 8, viewers will have a rare glimpse of the solar corona and everything that explodes from it.
If you are in the path of the total solar eclipse on April 8, you will experience a brief moment of darkness lasting a few seconds to a few minutes. This is the only safe time to look directly at the Sun without eclipse glasses.
During totality, as you observe the solar corona, you may see deep pink spires and charged plasma loops extending many times the diameter of Earth into space. In the most recent total solar eclipse in Australia on April 20, 2023, these “highlights” were stunning and vast.
A massive coronal mass ejection blasting over a billion tons of material into space. (Photo: NASA/Goddard Space Flight Center).
These highlights are almost certain to appear during the total solar eclipse in North America on April 8, as the Sun may be at the peak of its 11-year solar cycle, known as solar maximum.
Coronal Mass Ejection Magnification
A visible phenomenon is the coronal mass ejection (CME). Ryan French, a solar physicist at the National Solar Observatory in Boulder, Colorado, USA, and author of the book “If we are lucky, CMEs will appear as spiral structures, like the Sun, located high in the atmosphere,” explained: “CME is a massive release of magnetic fields and plasma from the Sun’s corona. It moves quickly but appears to stand still for hours.”
CMEs appear in a spiral form in the solar corona, occurring several times a month and lasting a few hours. Previous sightings occurred in 1860 and 2020.
The Moon’s shadow will take 100 minutes to pass over North America, so a CME could erupt just before that, and everyone could witness it under clear skies.
Solar Radiation
Solar flares are intense bursts of radio waves, visible light, X-rays, and gamma rays on the Sun’s surface that travel at the speed of light and take just 8 minutes to reach Earth.
Although three X-class solar flares—the highest intensity—occurred over a week last February, it is unlikely that such a flare will be visible throughout the entire duration.
Sunlight differs from CMEs—it occurs much lower in the Sun’s atmosphere, closer to the Moon’s edge, and can only be seen for a few minutes. They may be visible as red rings closer to the Sun’s surface.
However, the timing and position of solar flares and CMEs will be moderate. French stated: “To be visible from Earth, it needs to be above the Sun’s edge—so it isn’t obscured by the Moon—for a few minutes during the eclipse.”
Massive Eruptions
Physicist Ryan French added: “We will see highlights during the total solar eclipse on April 8. These highlights come in various sizes and are more common during solar maximum. Sometimes, these highlights erupt, breaking away from the Sun’s surface and expanding into the Solar System.”
It will be a spectacular sight, but what eclipse chasers truly want to see are the “massive eruptions”—ideally separating from the Sun’s surface and floating freely in the corona.
Red Glows
During the total solar eclipse, we may see red glows, red spires extending from the Sun’s surface to the corona.
French noted: “It is important to remember that the eclipse will still provide a view of fixed highlights, not eruptions. They will simply appear smaller and closer to the Sun’s surface compared to when they are erupting.”
These events occur very briefly. For a clearer view, one could board a supersonic jet and chase the Moon’s shadow. Scientists did this in 1973 using a Concorde jet, achieving a total time of 73 minutes.
