Four days of solar viewing

by Michael Swartz

Well I don't usually get to do solar viewing four days in a row but this week I guess I was just lucky.

Thursday I met James Adams up at Alice's restaurant on Skyline. We had a nice lunch and then drove south on Skyline to a turnout where we both set up our scopes and watched "del Sol" for a while. There was a very large spot group (#'s 424 & 425) with lots of magnetic turbulence or modeling surrounding them. There were filaments jutting up between them, spicules and lots of color. It looked like there was a bright yellow crack between them which might have been a source for a solar flare. Plenty of other large filaments across the front surface with some pretty fountain like prominences in a few places around the perimeter. It was very nice.

Friday I arrived at Montebello around 6:00pm or so and set up my gear. Rashad, Jeff, and a few others made it in early enough to set up their stuff and stiff have time for some solar viewing as well as friendly conversation. I have a Takahashi Sky90 with the Coronado 90mm SolarMax90 filter on the front and a BF30 blocker at the focuser end. I also added the hi-res module which is a 40mm etalon that screws into the focusing tube in front of the blocker. I also then use a diagonal, the Denkmeier binoviewer and two of the Coronado 18mm h-a optimized eyepieces. I will sometimes swap them out and use either the 16mm type 5 naglers or the 19mm panoptics. The coatings are different and so the contrast is also different. It makes for a striking comparison. I am not sure which I like better so during the course of a viewing session I usually use both the Coronado eyepieces and the TV eyepieces. The combination of the 90mm etalon up front and the 40mm etalon at the back end finetune the bandpass down to .5 angstroms Coronado says. Well, I don't know but I can tell you that the difference in visible surface detail is quite incredible. The view is very close to what you see in pictures. I have noticed though that the contrast and focus will vary in different parts of the field of view so using the RA and DEC adjustment knobs or the electric control to move the solar disk around brings out different details. So it is kind of fun to move it around and explore it. Sometimes like this week there are lots of really pretty things to look at.

Friday the 424 & 425 spot group moved more towards the center of the front of the sun. The bright crack I noticed between them on Thursday wasn't as bright. I noticed some more fountain like prominences and one really large filament. It was quite curved. It had two high points and extended for a really long way, perhaps 20% of the distance across the middle of the sun. And because it was at a slight angle from my perspective I could see some very distinct delicate structure in it.

Saturday I noticed that another large spot group was coming around into view.

Today I was joined by Steve Bryson and his lovely wife for a bit of solar viewing. The wind was pretty calm around 3:00pm where we were so the seeing was pretty good. Steve works at NASA and is studying the solar atmosphere so it was great fun looking at the sun together and learning from him. The group 424 & 425 had rotated quite a bit by now and seemed to be spreading out a little more. There were some new smaller filaments around them and the bright crack in between was gone. Some of the fountain like prominences I had seen on Thursday and Friday were now in front and viewed as filaments. It was an interesting contrast to see them now from the top and be able to recognize them. The tops of these fanned out and very fine detail was visible. Also from my view there was a huge prominence extending out really far at about the 2:00 position. It looked like a big flame with another bright formation of gas out past that. I could not tell if it was still connected or not. It may have been a solar mass ejection. But it was quite striking.

Like others have said, if you haven't seen the sun in H-Alpha, you haven't seen the sun. It is a very dynamic thermonuclear inferno. As stars go, they say ours is fairly average in many ways and fortunate for us is quite stable. But when you look at it you can see tremendous activity. The things we can see are quite large by comparison to the rock we live on so we don't often see rapidly transiting events. Most changes are subtle and are discerned over time but once in a while an event that happens over hours or even minutes can be seen. I've seen a spicule rise and then disappear. And I've seen a filament just hang out over the surface of the sun for days, or a week or more. And given that we are 93 or so million miles away, if we can see it with a small refractor. it's BIG!

Anyway, I'm not sure where I'll be next but if you find me somewhere with my solar stuff set up you are quite welcome to come and join me. Marvel at it and see why it is always good to wear sunscreen.