by Jane Houston Jones
Today we observed the solar chromosphere in H-alpha through our brand-new-just-opened Coronado SolarMax 60 with a T-Max 60 tuner, 10 mm blocking filter and with an adapter plate for our 70mm Televue Ranger. We ordered it in late April, paid for it in early June and it arrived in mid August.
Sky and Telescope reviewed the SolarMax system in their August 2002 magazine, so I won't belabor the technical details. It is a fixed wavelength, thermally stable filter for observating the Sun in H-alpha. The filter we purchased is comprised of two units: the narrowband element, and the blocking filter. The narrowband element includes the energy rejection filter which serves to eliminate infra-red heat from entering the instrument as well as cutting off the UV side of the blocking filter's rejection band.
I opened the box and was impressed that the two units come in a nifty hard black plastic eyepiece case much like the small Orion case. As soon as we had our Vixen GP mount set up and the battery plugged in, we mounted the Ranger on it. The SolarMax 60 screws into the adapter which screws right into the Ranger. The T-Max 10mm blocking filter replaced the Ranger's diagonal, and when we put a 19mm Televue Panoptic in the eyepiece barrel and took a look. We were absolutely gasping with amazement! The setup took less than a minute, too!
The sun was positively ringed with rim-flaring prominences! There were at least 12 of them around the limb. Then there were dark squiggly jet-like spicules, filaments, sunspots, shiny plage. A turn on the knurled wheel of the T-Max tilts the SolarMax front cell up to 1.2 degrees, which shifts the filter's bandpass as much as 0.2 nanometers toward shorter wavelengths. This tilt changes the view so features with higher velocities can be seen better. All of a sudden I saw more prominences.
I've only had short peeks through H-alpha before. Through somebody's telescope at RTMC or at a star party. I've never had the whole sun to myself for an extended time before. But in the half hour we observed the sun, we saw the most interesting event unravel.
There was one prominence at 10 o'clock on the solar disk -- a spiky pillar of florescent red. The base of it was brighter and shiny, appearing more like the shiny plage which appear around sunspot groups in H-alpha. While we watched, this pillar grew longer, and after about 10 minutes, half of it broke off, twisted and changed shape like a meteor's persistent train in the upper atmosphere as it dimmed and receded from view.
Was this a spray? Was it a solar flare? We took a couple images holding our Nikon Coolpix 990 to the eyepiece.
Theya re not good or anythig, but interesting. Here's one showing the ejection. You can see the large sunspot area in H-alpha in the far right of the image.
http://www.whiteoaks.com/jane/solar/sun-02aug16b.jpg
The original prominence then widenened at the base and eventually receded. Was this a surge? All the other prominences looked like fountains, or loops. But this one was amazing and I'd never seen any motion in a prominence before. All this in the first half hour with our new Coronado system!
