If you have a solar filter, check out the sunspot group AR 3190 that’s crossing the solar disk this week.

If you have a solar filter, be sure to have a look at the Sun over the next several days. Sunspot AR 3190, which is crossing our stars central meridian today, is massive — so big, in fact, that you can see it without a telescope by simply holding a filter to your eyes and having a look.

Sunspot group is black on the center of the yellow-orange disk of the Sun
The Sun, as seen by the Solar Dynamics Observatory, shows the immense active region AR3190 (at center).

Of course, the view is much more rewarding with a properly filtered telescope, as there are more than half-a-dozen smaller groups of spots riddling the photosphere.

Solar activity is rapidly increasing as we head towards the maximum of the Sun's 11-year cycle, which should peak in 2025. Long-time Sky & Telescope contributor Tom Fleming notes he's seen more sunspots this week than any time since Cycle 25 began a few years ago. So if it's clear and you have a safe solar filter, be sure to have a look! Observers with small refractors lacking a solar filter could also see the spot by projecting the image onto a piece of paper. Just be careful not to look at the Sun through the unfiltered telescope.

diagram of solar projection
A simple projection setup made from a cardboard shield and a piece of white paper as a projection surface. A surprising amount of detail can be seen this way.
Sky &a Telescope illustration

To read more about safe solar imaging, check out the November 2022 issue of Sky & Telescope.




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