Neither of us had been much of a solar observer. We'd only had white-light filters: filters you put over the front of a regular telescope to block out most of the sun's light so you can see sunspots.
H-alpha filters are a whole different beast:
you can see prominences, those huge arcs of fire that reach out into
space for tens of thousands of miles, many times the size of the Earth.
And you can also see all sorts of interesting flares and granulation
on the surface of the sun, something only barely hinted at in
[ 12:00 Mar 07, 2022 More science/astro | permalink to this entry | ]