Large dark spots are visible on the surface of the Sun, under certain conditions
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Observing sunspots with the naked eye is an activity that many civilizations have done before us. And even if this turns out to be possible, including when solar activity is not at its maximum, the current period is particularly favorable.
Remember before continuing that it is dangerous to watch the SoleilSoleil in front without protecting his eyes. Its radiance infraredinfrared can burn the retinaretina in a fraction of a second. So if you plan to get started, bring certified glasses or project the image of the sun on a sheet of paper to avoid any accidentaccident unfortunate.
With this caveat in mind, it should also be pointed out that observing sunspotssunspots at theeyeeye naked is done especially in particular conditions. When the lightlight of the Sun is attenuated. Through the fog, through cloudsclouds purposes, at sunrise or sunset or when dust is present in theatmosphereatmosphere.
For a sunspot to be visible to the naked eye, it must also be large enough. Of the order of some 50,000 kilometers in diameter, at least. That is about 4 times the diameter of the Earth. And it just happened last January, for example. The AR3190 spot appeared in footage of a SpaceX Falcon rocket liftoff. Or currently, with active regions AR3310 and 3312.
THE astronomersastronomers estimate that 2 to 3% of sunspots reach this size, or around a hundred per cycle. Especially around maximum activity. In the current period, therefore.