Saturday, December 20, 2014

Sunspot Hexagon

Lots of Spots

I thought my previous solar observing session would surely be the last of the year. But a combination of favorable conditions on December 17th made it hard to resist another look at the Sun. It was 54 degrees, with clear skies and a gentle wind, and the Sun had recently produced a swarm of sunspots.

Wearing only a light jacket I set up my equipment and expected the usual efficient, trouble-free start of observations. Not this time! Something was wrong with the Internet connection. The mount control software could not synchronize with a standard time source. Finally, after many wasted minutes restarting the computer and resetting the modem/router, the software's clock was eventually set to the correct time. In the next step, apparently, the mount did not properly reach its initial "home" position. Consequently, the telescope did not point toward the Sun when commanded to slew there. Then a wire got caught between moving parts in the mount causing the mount to jam. I shut everything down and restarted. The mount, once again, did not properly home. So I pointed the telescope manually toward the Sun and disconnected the mount from the computer. Since the mount is nearly polar aligned, it still tracked the Sun very well. I used the hand controller rather than the computer to move around the Sun. After all this I was, finally, able to successfully gather images. I'm really nervous about the homing error. This has never happened before. I hope it can be corrected without sending the mount back to Software Bisque. 

In spite of the initial difficulties I enjoyed capturing a spectacular array of sunspots forming an irregular hexagon centered on the solar disc. The following imperfect 16-image mosaic shows a beautiful variety of features spread across the disc. (Click on the images below for larger views.)
Next is a closer detailed view of the irregular sunspot hexagon.
The two largest sunspots are at the bottom of the previous picture. Spot 2241 is the one on the left. Spot 2242 is on the right. The following image is a closer view of these two showing lots of complicated structure in good detail.
These images were captured only 4 days before the winter solstice when the Sun is lowest in the sky. My wonderful new observing site makes imaging possible all year round.

Friday, December 12, 2014

December Sun

Anomalous Warmth

Winter is approaching. The Sun ignores Earthly seasons.

I've never used my solar telescope in cold December, but, on this December 1st, it was 65 degrees, warm enough to observe in a t-shirt! At my previous home in Lynchburg the Sun was hidden behind trees and houses in December. At my new home Sun-blocking obstacles don't interfere. The seeing was surprisingly decent in spite of persistent southerly wind. Sunspots, filaments, and prominences were on display.

The following 36-image mosaic shows most of the solar features visible on December 1st. The western edge of the Sun (on the right) has many filaments, some small sunspots about to rotate out of view, and large prominences on the rim. Single sunspot 2218 is above center, and large sunspot 2222 is below center. All these features show up particularly well in a larger view. (Click on the images below for larger views.)
The previous image was constructed from the best 40 frames of individual 400-frame videos. The next image was constructed from the best 100 frames of individual 1,000-frame videos. Details are slightly sharper in the following 16-image mosaic.
I was pleased with the fine detail in the following close view of sunspot 2222.
Finally, I attempted a 17-image mosaic of prominences. Unfortunately, this mosaic is imperfect. Brightness is uneven around the circle because my best mosaic-making software, for some reason, refused to construct a circle from the 17 separate images. Photoshop Elements was able to make the circle, but did a poor job blending pictures of different brightness.
The weather has turned ugly since December 1st. Even if I'm unable to observe again in 2014, I've had my best observing year so far.

Thursday, December 4, 2014

Giant Sunspot Returns

Enormous Spot Lives On

On November 15th observing conditions were not ideal. The afternoon temperature was a chilly 45 degrees. Seeing was poor, and the Sun was low. Nevertheless, it was an opportunity to observe the return of a monumental long-lived sunspot.

Sunspots come and go, but, occasionally, they can last for weeks. Sunspot 2192 ranked among the largest spots observed in recent times. After rotating westward across the Sun's disc for more than a week, it disappeared around the western limb on October 30th. The Sun continued turning, and the spot crossed the Sun's back side for 14 days. It then reappeared on the eastern limb on November 13th. The following 9-image mosaic shows the enduring spot on November 15th. The long-lasting spot had been renumbered as 2209, and appears at lower left.
Huge prominences also appeared on the eastern limb making a dramatic mix of features as shown in the following 6-image mosaic.
Next is a closer view of sunspot 2209 alongside a properly sized image of Earth so you can see how large the spot truly is.
I set up equipment too late this day. The afternoon Sun lost altitude quickly, and increasing clouds destroyed a previously clear sky. This observing session ended after only 31 minutes. It might be my last session for the year now that it's getting too cold for comfortable work with the telescope.

Wednesday, November 26, 2014

The Virginia Capital Trail

Sherwood Forest Section

Since moving to Williamsburg I've been waiting, waiting, waiting for the unfinished Virginia Capital Trail to be complete. Finally, finally, finally the Sherwood Forest section has been completed! The official dedication took place on October 15th, but the trail was open to biking a few weeks before the 15th. The Sherwood Forest section runs along Route 5 from just west of the Chickahominy River Bridge to Charles City. I took some pictures along this wonderful new trail on a sunny fall morning. Share the scenery with me as we ride westward from Chickahominy to Charles City.

The newly completed trail begins with these views after crossing the Chickahominy River Bridge.
The trail runs parallel to Route 5, sometimes very close to the highway.
Historic signs are posted just before the intersection with Wilcox Neck Road (623). The intersection itself is not particularly busy.
The next segment, between Wilcox Neck Road and Sandy Point Road, has some nice wooded sections, although it never strays far from Route 5.
After passing Sandy Point Road wooden bridges become more common.
At Sturgeon Point Road another set of historical signs are nicely placed beside the trail.
A beautiful tree-lined stretch brings the trail past the entrance to Sherwood Forest.
One of the prettiest parts of the trail is just past Sherwood Forest. Fields of ripening soybeans glowed yellow in the late morning sun. Long open lines of sight look out over farmland.
Within a few miles of Charles City more wooden bridges appear.
After crossing the wooden bridge above a long open section passes fields surrounding the Burlington Plantation on the left.
Charles City is not far away now - just beyond this long bridge.
The trail crosses to the south side of Route 5 just before Charles City and then passes through this brief scenic stretch.
At the intersection of Route 5 and Route 155 the trail swings up into Charles City on a concrete sidewalk.
Charles City is not what most people would call a city. It's a small collection of county administrative buildings and a visitor center at the historic Charles City Courthouse. Here's the historic old courthouse.
There seems to be a conflict between the construction dates on the two signs. Was the old courthouse built in 1730, or 1757? Across the road from the old courthouse is the Courthouse Grill.
A short ride down this road through Charles City leads to the continuation of the Capital Trail which goes on for about another 7 paved miles at this time.
Charles City is just about at the 20-mile point along the Capital Trail. The zero-mile point is located at the Jamestown Settlement. It's a beautiful ride on a sunny fall day! 

Tuesday, November 18, 2014

Powerful Solar Flare!

Tremendous Eruption

Magnificent sunspot 2192 produced a dramatic explosion on October 25th! After setting up my telescope and centering on 2192, the first image on my computer screen showed a huge flare erupting from the midst of the sunspot group! The flare was completely overexposed and white, as you can see in the first image below taken at 1:57 EDT (17:57 UT).
The flare diminished as time went on. At 3:06 EDT (19:06 UT), just 69 minutes after the first image was captured, the sunspot group looked like the next image. The overexposed white area had shrunk significantly.
The flare peaked at 1:09 EDT (17:09 UT) according to space weather websites. So my first observation was 48 minutes after the officially reported peak. The flare was diminishing at this time. If I had begun observing an hour sooner, I would have captured the rise of the flare toward its peak instead of its decline.

This was an X1 flare, the most powerful class of solar flares. Solar flares are classified according to their rate of energy output in X-rays. An X1 flare gushes energy at a rate greater than 0.0001 watts per square meter in X-ray wavelengths between 0.1 and 0.8 nanometers as measured by detectors in geosynchronous orbit around Earth. This 0.0001 watts may not seem like a lot of power per square meter, but this is the flux measured near Earth far away from the concentrated source on the Sun. By the time X-rays travel to Earth from the Sun they have spread out over a tremendous area. A square meter near Earth receives only 0.0001 watts, but at the source on the Sun energy is emitted at the rate of about 14 billion gigawatts!!! That's equivalent to the power output of 14 billion nuclear power plants!! It's a good thing we're so far from the Sun!

The next picture is a 22-image mosaic showing features spread over the solar disc. Sunspot 2192, with the white flare winding through its middle, is right of center. A very long dark filament runs horizontally above center. Modest sunspot 2194 is below center and sunspot 2195 is left of center. (Click on the image for a larger view.)
The immense dark filament stretching horizontally above the disc center is many, many times larger than Earth as shown in the next image where a comparison Earth is superimposed below the center of the filament. It may be hard to see the Earth image at first because, unfortunately, it seems to blend in with the background.
After collecting images for the disc mosaic above I thought the active sunspot might still be changing enough to make an interesting movie. So I recorded movie frames, one every 60 seconds, beginning at 3:08 EDT (19:08 UT). When 30 minutes had elapsed it seemed like nothing was happening, so I stopped recording at 3:38 EDT (19:38 UT). The 31-frame movie below shows the aftermath of the flare. At the beginning of the movie white areas are brightest. Over the next 30 minutes brightness diminishes as the flare continues to die down. The spot was perfectly positioned for making a long movie. I gave up too soon! Lots of details are changing within the sunspot group, although these changes weren't easily apparent as I captured video clips one by one. (Be patient while the movie loads. If it doesn't play automatically, click on it.)
Sunspot 2192 eventually rotated out of sight around the western limb on October 30th. It continued to exist for another 14 days as it rotated around the back side of the Sun. Then it reappeared on the eastern limb on November 13th. Maybe I can observe it again in November if conditions permit.

Monday, November 10, 2014

Tremendous Sunspot 2192

Marvelous Sunspot Now Faces Toward Earth

A period of beautiful weather continued on October 21st: ideal conditions with temperature in the upper 60's to low 70's. Showpiece sunspot 2192 was still on display looking better than ever. It's hard to judge the size of this enormous sunspot group without a normal-sized sunspot nearby. You can compare 2192 with just such an ordinary sunspot in the next picture, a 2-image mosaic showing typical sunspot 2194 to the lower left with monster 2192 in the center.
An extremely long filament was also present in the northeastern quadrant of the Sun.
This filament was only partly around the eastern limb four days ago on October 17th.
Since mighty sunspot 2192 was so active, I tried recording another time-lapse movie. Only minutes after recording began at 2:37 pm EDT communication between my computer and the telescope mount was broken. Fortunately, the mount kept tracking. After about 18 minutes a flock of clouds began moving into a previously unblemished sky from the south. I was forced to stop recording for about 3 minutes while a cloud passed over the Sun. There were gaps between clouds, but clouds were thickening. After 35 minutes the situation became impossible. The whole southern sky was covered with clouds. What a shame! The sunspot was just starting to do interesting things when clouds ruined everything. Nevertheless, I used the 28 still frames I was able to capture to construct the following movie showing about 35 minutes of activity from 2:37 pm EDT to 3:12 EDT (from 18:37 to 19:12 UT). Notice blinking white areas and the surge coming below the largest umbra just as the movie ends. Although the movie frames are not all equally spaced because of the cloud interruption, the movie doesn't look jerky. When some thin clouds passed in front of the Sun they caused a brief darkening. Unfortunately, the eruption below the sunspot was just beginning when thick clouds ended the session. This eruption seems to be coming from under the penumbra as though the penumbra was a lifted lid on a boiling pot. (Be patient while the movie loads. If it doesn't play automatically, click on it.)
The cursed clouds ruined a good opportunity to observe more seething action in this magnificent sunspot.

People say I'm crazy doing what I'm doing
Well they give me all kinds of warnings to save me from ruin
When I say that I'm o.k. well they look at me kind of strange
Surely you're not happy now you no longer play the game

People say I'm lazy dreaming my life away
Well they give me all kinds of advice designed to enlighten me
When I tell them that I'm doing fine watching shadows on the wall
Don't you miss the big time boy you're no longer on the ball

I'm just sitting here watching the wheels go round and round
I really love to watch them roll
No longer riding on the merry-go-round
I just had to let it go

John Lennon