Cracking Sunspots

Some of the best sunspots of the new solar cycle so far, taken this morning, 31st July.

Imaged through my normal set-up of D300, 420mm telephoto (300 + 1.4 TC) and Baader solar film. 20 images stacked in Registax and colourized in Photoshop CS3.

Forgot to label the image whilst processing, so - the 3 main spot groups (from bottom to top) are active regions AR1263, 1261 and AR1260. AR1265 is the small single spot to the upper right of AR1260.



AR1263, 1261, 1260 (bottom to top)



Last Voyage of Atlantis

The very final Space Shuttle journey into orbit.

According to CalSky.com there are several solar transits this week, creating some last-chance imaging opportunities. Ideally I wanted to try and image Atlantis as a separate object to the ISS, as it's tricky to reliably identify once it's docked. So, all that was needed was a transit to occur either just before or just after docking, some clear skies for the critical second, and knowing where to set-up my camera gear.

By good fortune, CalSky.com was predicting a pre-docking transit with the centreline crossing England just north of Corby for early afternoon on Sunday. So, armed with camera's, scopes, laptops and a sat-nav, my mate Dave and I headed off in good time to set-up. Using Google maps, we'd identified a convenient entry into a field just north of the village of King's Cliffe, so off we went.

Cloud cover was a major worry and initially hampered Dave's attempts to find best focus through his scope, but as transit time approached the clouds began to clear and the adrenaline started pumping. For those who haven't tried transit imaging, the emotions are hard to describe. The transit was predicted at lasting only 0.56 seconds, so everything had to come together exactly at the right time. No second chance. Camera alignment, focus settings, self-timer settings, exposure settings being changed down to the last second to compensate for varying cloud cover, clock-watching to get the start of automatic exposures timed just right. And of course - would the clouds be clear of the sun for the critical second. Excitement, anticipation, panic, nerves, apprehension.... they're all there.

I'm pleased to say it all came together - here's the results.

Details -

Size of ISS = 60.1".
Distance from camera to ISS = 460km.
Transit duration = 0.59s
Images taken 2h 27m before docking.

Nikon D300 + 420mm telephoto + Baader solar filter.
Continuous exposure settings set to take 5 fps for 20 seconds at 1/1600s and f8. ISO 200, starting at 13.39 and 44 seconds BST.



A field somewhere near King's Cliffe




Worry - will the cloud spoil the day?




ISS at 13.39.56 seconds (2 image composite)




Close-up, passing across a field of sunspots




Atlantis - spot it if you can!




Atlantis 13.39.58 seconds (2 seconds behind and in hot pursuit of ISS)




Close-up! Passing between sunspots AR1249 and 1245




Path of ISS and Atlantis.



More Shadow Chasing

It's only a few days before Endeavour undocks from the ISS and returns to Earth. Unfortunately, there are no solar transits visible from the UK after undocking, so this imaging session was to try and improve on my previous "docked" image. Endeavour is the dark blob situated between the solar panels, which are also better presented compared to my last post. I was chuffed to get 4 images so, overall, I think this is a more pleasing composite than my last effort. Images taken at Maple Cross, Herts. on 24th May.

Due to the resolution limitations of my camera and lens (420mm), I think this is the best I can achieve with my current set-up. In the raw images, the ISS is only about 25 pixels across, so there's not much data to play with! I need to increase the image scale which means getting one of my scopes set-up for solar imaging. Another project to add to the growing list.

ISS/Endeavour at 10h55m and the all important 24seconds.... (and sunspot 1216)

A very fuzzy Endeavour

Shadow Chasing - Endeavour crosses the Sun

After yesterdays disappointment, the weather today was forecast to be worse, but I checked out a favourable spot anyway to try and image the ISS and Endeavour transit, predicted for this morning at 11.43 and 38 seconds. I've only got 3 attempts left to try and image Endeavour before it's pensioned-off, so I had to try and hope for better luck than we had yesterday.

When I arrived at my chosen site near Pulloxhill, Beds, I parked up in a convenient field ......and it started to rain. "What am I doing here?" I asked myself. As the wind was blowing the cloud along at a fair pace I thought I'd stick it out and hope for the best. Fortunately, 10 minutes before the transit started a big patch of blue blew across the sun and everything was looking good.

No other mishaps, and I started my 100 exposure sequence 10 seconds before the predicted start, at a rate of 5 fps, using my laptop on the car seat to get an accurate time fix.

Back home, I was delighted to have captured 3 images which are composited here. The other dot on the sun is the sunspot AR 1216. The enlargements show some detail - one of the sets of solar panels is very clear, though I'm not 100% sure which bit is Endeavour. I suspect it's the dark blob near the centre.

Duration of transit only 0.57 secs. Shadow ground speed 7.5 km/s

Diameter of ISS = approx 65.4 arc seconds

In a field somewhere, with my DSLR and 420mm lens



Nice cuppa, shame about the cloud

Would you believe it.

My pal Dave and I set-up our gear in his garden, in glorious sunshine, and awaited the ISS transit predicted for 9.45 this morning, with DSLR's and webcams at the ready. With about 1 minute to go, the only cloud to cover the sun during the whole morning slowly moved across the solar disk and we were plunged into shadow. I started exposures as I'd planned anyway - starting 10 seconds before the transit - in the hope that a break in the cloud at the crucial second of transit might appear. Sadly, no such luck and, as if to poke fun at us, the cloud slowly moved away from the disk 10 seconds after the end of the transit! The sun appeared on only the last few frames of my 100 exposure sequence. "Oh dear, never mind" we said to ourselves!

Oh well, the cuppa helped calm the stress and frustration at having missed the event.

Dave's superb observatory with my modest DSLR in front

The offending fluffy stuff

Peekaboo - 10 seconds after the end of the transit!



The one that got away...

Motivated by my previous ISS transit success, I thought I'd have another try today. The centreline was predicted to pass through a local nature reserve (Paxton Pits for those that know it) so if I was clouded out at least I could try and photograph some interesting wildlife.

With 30 minutes to go, things began to look dodgy. I rattled off 15 images to check my exposure settings and then waited impatiently. To my dismay, the clouds won the day and with 15 minutes to go there wasn't a patch of blue anywhere to be seen.

This image was taken from the 15 test images and shows some minor sunspot activity and a bit of faculae, so all was not lost.

Oh, and I didn't get any bird pictures either. Some days are like that, aren't they? Anyway, trying again tomorrow, as there should be an ISS transit visible from my friends back garden....weather permitting. At least we can have a cuppa while we watch the clouds roll in!



No, not the ISS - just a few sunspots.



ISS Transit ID

Following some searching on the web, I've tried to identify the different parts of the ISS that (with a small stretch of the imagination!) can be seen in my image of a few days ago. The solar panels can be rotated to suit the sun's position relative to the station, and are shown at a slightly different angle between the two dates.

As a rough guide to image scale, the area covered by the four sets of solar panels is 361 ft wide x 240 ft long.  The station was imaged at a distance of around 250 miles. As best as I can estimate it, the theoretical resolution on the original image works out at roughly10ft per pixel.

ISS Solar Transit - 13th May 2011

First time I've tried to image the ISS crossing the sun. Seen lots of great images on the web, but naiively thought I'd need more sophisticated gear than I currently have.  Anyway, while browsing the web last night, I happened to check the ISS transit programme on CalSky just for interest. I was surprised to see that the centreline of the next transit was today, a mere 3km from my house. Too good to be true I thought, so I decided to give it a go and hope for the best. The total transit duration was predicted to last only 0.5 secs, so my timing needed to be pretty accurate.
Anyway, here's the result. I have to say I was dead chuffed. The close-up clearly shows the solar panels, with the station modules lying between, at an orientation of what looks like approaching end-on.

Details - 420mm telephoto with Baader solar film. 1/1250s at f8. 100 images taken at 5fps starting 10 seconds before the predicted start of transit.



Composite of 3 images taken 0.2 seconds apart





AR 1176

Following my last post, I was hoping the fine weather would last long enough to allow me to capture the developing active region 1176 as it moved across the disk.  How optimistic was I?!

So, with the attempt aborted after only 3 days, here's another post showing the developing sunspot group as it moved away from the limb.

Unfortunately, the sky today was a bit hazier due to the approaching front, which messed up the image clarity slightly compared to the earlier shots, but I've done my best to get the contrast and hue the same for all 3 images.  The result, whilst not as good as I'd hoped, is quite pleasing and shows the changing aspect of the spot group reasonably well. A larger image scale on the camera sensor would allow me to capture more detail. When I eventually get my scope out of hibernation, I must try and hook the DSLR up, giving me a focal length of 1600mm, instead of the current 420mm. That should hopefully spice things up a bit!

Sun - 23rd March 2011

A while since I've taken any images of our nearest star so, blessed with some decent weather, I thought I'd capture a few images.
This shot is a 10 image stack taken with my trusty D300 and 420mm telephoto.

Active region 1175 is starting to creep behind the limb; no discernible sunspots are visible, but there is some nice faculae. Meanwhile, AR1176 is beginning to show itself on the opposite side of the disk, with some interesting spot development amidst the faculae. This group has the potential to grow into something quite large, so will be interesting to track it's progress as it crosses the solar disk. Hopefully we'll be granted a few days continued clear skies before the cloud rolls in.

23rd March. AR1175 & AR1176

Perigee Moon

To the unaided eye, the full moon at perigee is, despite media hype, not noticeably larger than any "average" full moon. Never the less, it was interesting to observe as it climbed above the horizon, falsely coloured and slightly oblated due to it's low altitude, and to capture a few images of the event for the record. 
Without a useful point of reference to compare the image to, of course, the apparent 14% increase in diameter is largely meaningless.  What would be much more interesting would be to capture an image of a similar phase moon when it is at apogee, and to composite the images. This would enable a more meaningful and interesting size comparison.  So, I have the perigee image, now when is the next full moon at apogee.....?



Perigee.  19th March 2011



Crescent Sun

With the predominantly cloudy weather of late, I missed the Quadrantid meteor shower, despite staying up until after 3.00am this morning. So, after only 4 hours sleep, I amazed myself by waking in time to try and catch the partial solar eclipse. Venus blazed away in the South as I peeped through the curtains, which shocked me into hurriedly getting dressed and collecting my camera gear.

I wasn't sure what time the sun would manage to creep over Shearhatch Wood, so was lucky to arrive just before it showed it's face. The hazy clouds near the horizon made for patchy viewing, but I think gave the scene a little more atmosphere. These are a few of the images I managed to take before the sun disappeared permanently behind the growing cloud. I think I was lucky to see it at all!

Images taken with DSLR at 420mm through Baader solar-film.

Sunrise over Shearhatch - 08.26 UT

08.33 UT

08.36 UT

08.52 UT