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ISS solar transit - Friday 10 and Tuesday 14 June

Started by Roberto, Jun 08, 2022, 11:21:21

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There are a few solar transits of the ISS forecast for this Friday (one at 4PM) and two for next Tuesday (one at 11AM and another at 2PM) which should be observable from Sidcup, Chislehurst and Bromley:  https://transit-finder.com/

I may take Friday afternoon off from work (depending on weather) to image the first from a lay-by on North Cray Road in Sidcup.  Details of that pass - at that specific location where it is maximum and central on the disk of the Sun - are:

Friday 2022-06-10, 16:00:20.02
ISS angular size: 47.63″
Az.: 248.2°; Alt.: 45.2°
Transit duration: 0.83 s

Anyone interested in imaging it with me in white, Ha or CaK light?  The transits on Tuesday are at higher altitudes and the ISS will be slightly larger (54"), durations are slightly shorter 0.65s.



If you want some company (bit exposed on your own on a public layby) I could come and keep you company if you tell me exactly where and when.  I don't do solar imaging any more, but would be interesting to watch. 

Presume you can't get a good view from home?

E Mail me Roberto.



Cool finder. Good luck with the weather and imaging. :)


Hi Carole

Thank you.  I think there a few places to park and hopefully it should be very quiet.  I will write to you separately by tomorrow depending on the weather forecast.  This would be my first attempt at imaging an ISS solar transit and could end up being a complete waste of time!



QuoteI don't do solar imaging any more, but would be interesting to watch.

Make sure you dont blink. its over in less than .5 of a second.
Interesting web site, havent seen that one before, its amazing exactly how many passes there are.

Might have to get a few lined for when im next home.



Although some passing clouds are forecast, the weather for tomorrow afternoon seems to be fine to image this.  I am going to park at the north end of Leafield Lane just off the A223:  Leafield Lane - Google Maps

I'll be there at around 3:15-3:30pm. 

Mac, indeed this transit lasts 0.83 seconds!  I'm not observing it ... it'll be captured on video.  Don't even need a tracking mount for it.



  I'm not observing it ... it'll be captured on video.  Don't even need a tracking mount for it.

Good plan so aa long as you are videoing the Sun you'll catch it.  Sounds easier than trying to catch the ISS on a normal transit.

Not that anything astro imaging wise can really be described as easy. Lol



Well Roberto found a field near the busy main road and set up there instead of the layby,  with me for company. 

I will let Roberto tell you about the actual capture and the clouds.  But a nice social event anyway.



Carole - how lucky were we?!  8)  :lol:

Firstly, as Carole mentions, the common which is on a street behind the busy A223 was easy for parking with plenty of shadow and an open flat field to set up the telescope.  Right under the centre of the transit path.

We set up the Zeiss Telementor I took to the Starbecue and firstly used a white light Herschel wedge to get the Sun centred.  There were no spots of note on the face of the Sun but a nice group is starting to turn into view so watch out for them.  The double stacked hydrogen alpha etalon was then used and we had a quick peek at the sun before sliding the video camera in to prepare for the main event.  I took a couple of videos of the sun to have at least an image of how it appeared at the eyepiece:

Clouds started to move across the face of the Sun with minutes to go before the event.  :o  :-?   We let the video roll for a minute either side of the time of the pass without knowing if the transit had been captured. Remember it took only 0.82 seconds (!) and clouds were still moving off the face of the sun.   

I was not convinced it had been captured so started to pack up.  Carole sat in the shadow and went through the video and caught the transit!

I'm posting a link to the video (for details) as well as the video itself:


The video is shown at 12fps versus 146fps actual during capture.

Below is a composition of 34 images (out of 136 that had the ISS on it) showing the path of the satellite across the face of the sun:

Many thanks to Carole who kept me company and found the ISS whizzing across the sun in the video!

Remember there are a couple more passes - at the same location in Sidcup on Tuesday late morning and early afternoon in case anyone is interested.  I cannot image those (at least not yet but will check at work) so hopefully someone else can.  A transit so close to home is not that common so make the most of it!




As you say Roberto, just a bit of luck the transit was fractionally later than the predicted time, and just enough time for the annoying cloud to move out of the way, but we didn;t know if you captured it until after examining the video afterwards. 

I find it pretty difficult to look at a PC screen in the bright sunshine with all the reflections etc, which was why i tok myself into the shade.

Sharing the event added to the experience which is why DSCs are so great.

So glad you succeeded after all your effort of research, taking time off work and setting up in an away from home location.

I already posted it on the OAS Whatsapp group as I know many of them don't look at the forum.