Free course

Astronomy with an online telescope

The standard view of this forum does not always work well with assistive technology. We also provide a simpler view, which still contains all features. Switch to simple view.

You need to be enrolled on this OpenLearn unit before you can participate in this forum. Enrol now.

Picture of Johanna Jarvis

Johanna Jarvis Post 1

12 Oct 2020, 16:37

Week 8 Discussion

This forum thread is for discussion of topics related to week 8 of the course.

Picture of Michael Dodd

Michael Dodd Post 2 (summarised) in reply to 1

18 Nov 2020, 20:18

Light Curve Reading

 Dear Jo, Thoroughly enjoying the course - informative,...
 [Expand all posts]
Picture of Michael Dodd

Michael Dodd Post 3 (summarised) in reply to 1

19 Nov 2020, 12:41

EW2 Light Curve

 Dear Jo/Alan, Further to my initial post, I have now tried a...
 [Expand all posts]
Picture of Johanna Jarvis

Johanna Jarvis Post 4 (summarised) in reply to 3

19 Nov 2020, 15:16
Hi Michael, Thank you for getting in touch and I'm really pleased to hear you...
 [Expand all posts]
Picture of James Fleeman

James Fleeman Post 5 (summarised) in reply to 1

23 Nov 2020, 12:07

Light Curve

 Hi Jo, I've so enjoyed this course, and the opportunity to take...
 [Expand all posts]
Picture of James Fleeman

James Fleeman Post 6 (summarised) in reply to 1

23 Nov 2020, 12:49

Re Light curve EB1 pics

 See screen shots!
 [Expand all posts]
Picture of Alan Cayless

Alan Cayless Post 7 (summarised) in reply to 6

24 Nov 2020, 09:24 Edited by the author on 24 Nov 2020, 09:28
Hi James; Thanks for asking about these images. It's great that you've got...
 [Expand all posts]
Picture of James Fleeman

James Fleeman Post 8 (summarised) in reply to 7

28 Nov 2020, 15:07
Hi Alan, Thank you for your reply, and for the course. The image serial...
 [Expand all posts]
Picture of Alan Cayless

Alan Cayless Post 9 in reply to 8

30 Nov 2020, 14:08

Hi Jim;

Thanks for those image serial numbers - will check them out.

Your account will be valid for six months from the date you registered.   If you find you need some more time, do let us know.


Picture of Dennis Ramirez

Dennis Ramirez Post 10 (summarised) in reply to 9

30 Nov 2020, 16:30

definition of flux

 I am near the end of the course therefore I would like to...
 [Expand all posts]
Picture of Johanna Jarvis

Johanna Jarvis Post 11 (summarised) in reply to 10

1 Dec 2020, 16:25
Hi Dennis,  I'm so pleased to hear that you have enjoyed the course and it...
 [Expand all posts]
Picture of James Fleeman

James Fleeman Post 13 (unread) in reply to 9

17 Jan 2021, 17:44

Hi Alan,

I've just taken the final badge test, so have completed the course.

I'd like to thank you and Jo again so much for it. It has been such a pleasure for me, especially so in these difficult times.

If you have any recommendations regarding further study, I'd be very grateful tohear them. I read mention on this forum of a module that would further study in this area, but was unable to locate it or the course it was part of. I'm guessing my CSE Grade 1 in physics and O level maths won't set me up for a degree in Astronomy, but I would like to further the knowledge and interest I have.

I haven't received any images from Coast since before Christmas - I'm guessing the Coronavirus is responsible for that. But my subscription period will end next month and I would love to extend it. I cannot find out how to do this on the site, and am not sure about cost. I'm a professional musician so still effectively without income as I have been since March, and funds are limited!

Many thanks again, and thanks in advance for any reply!

Best wishes.


Picture of Alan Cayless

Alan Cayless Post 14 (unread) in reply to 13

18 Jan 2021, 09:48 Edited by the author on 18 Jan 2021, 09:50

Hi Jim;

Thank you for these comments, and for taking part so enthusiatically in the course.

COAST has been offline for a while, partly as a result of some technical issues and also (as you may have seen from the webcam) as the site has been covered with snow and ice for a while which has meant that the domes can't open.  It does seem to be brightening up now though so we hope that observations will resume soon.

It's great that you'd like to take your astronomy studies further.  We do have some other astronomy-related short courses here on OpenLearn (for instance Galaxies, stars and planets) - and if you do decide to go for more advanced study, several of our mainstream astronomy courses, including SXPS288 Remote experiments in physics and space, offer the opportunity to carry out more advanced projects using the OpenScience Observatory telescopes.

There's a post with some more information and links in the FAQ thread:


Picture of Robert Charlesworth

Robert Charlesworth Post 22 (unread) in reply to 13

26 Jan 2021, 03:23

Hi Jim,

I have just completed the course too, and would like to echo your sentiments. I thought the course was well designed, and the response of Jo and Alan on the forums here has really helped. It has given me something to focus while largely stuck in the house. I signed up in July, so my telescope access expires at the end of this month. I wasn't able to study every week for health reasons, but at least I could set my own pace, and I made it to the end!
I was a semi-professional musician for many years, supplementing a fairly meagre income by building (and occasionally programming) computers. I still did gigs with a band until about a year ago, but of course all of that has dried up, and now I'm completely unemployed, with no prospect of things improving.
I actually have a degree from the OU in IT & Computing, but that was over a decade ago and it's no use to employers any longer. In fact I find it's more of a handicap to me, since I can't access any funding for undergraduate-level courses, even on a loan basis. When I started you could get grants to study if you were on a low income, but now funding is a problem across the board. I am looking to retrain really, since lockdown has made it painfully apparent to me that I am no longer going to be able to make a living out of music or IT, and would like to get more into astronomy, or even telescope design - I had some contact with the Bradford Robotic Telescope team which designed the site and the original hardware, and I found it fascinating.

I first got interested in astronomy at school, reading Patrick Moore's books and watching the TV programmes - I suppose a lot of people did! Last year I dug out a copy of The Sky at Night observing guide and started to tick off the objects in the "Moore Winter Marathon" with my 8X42 binoculars. I've done most of them now, but I still can't get a clear view of the Sirius cluster M41. Some of them, like M67 (an old cluster in Cancer, much fainter than the Beehive) just look like little fuzzy patches in my binoculars, so it is nice to be able to "take" some images of them where I can actually make out individual stars.

I came across this course through the organiser for a local astronomical society, after I'd emailed him about the comet which passed close to earth last year - "2020 F3 (NEOWISE)". Apparently they have a telescope in a dome in the grounds of a local school which they can access, but they haven't had any meetings since the pandemic. Hopefully they will be able to meet in the future, so I can get some practical experience of using a telescope. It's not ideal because of light pollution, so I'm not expecting to get the same quality images as we get from COAST, even with a camera attached. Is there a society near where you live?


Picture of Alan Cayless

Alan Cayless Post 12 (summarised) in reply to 8

2 Dec 2020, 10:25
Hi Jim; Thanks for the serial numbers. I've checked these images out.  The...
 [Expand all posts]
Picture of Graham Womack

Graham Womack Post 15 (unread) in reply to 1

20 Jan 2021, 11:54

EA4 discrepancy

Hi Jo,

I chose the variable star EA4 for my observations, selecting 4 different exposure times as recommended. Unfortunately when they finally arrived (after the delay due to problems at COAST), the images bear no resemblance to the sample image provided on the course. Therefore I'm having trouble identifying the target and reference stars. Would this be due to the alteration in the night sky during the delay? I would have thought that using RA and Dec co-ordinates would have taken this into account.

Thanks in advance


Picture of James Fleeman

James Fleeman Post 16 (unread) in reply to 15

20 Jan 2021, 13:43

Hi Graham,

I just thought I’d share a few tthoughts while you’re waiting for Jo’s reply. They may be useful to you or others. Of course you may well have tried them all. 

I’ve taken a few exposures of two variables and each time had to hunt for the target and reference. I don’t think my brain is hardwired for good pattern recognition, so it wasn’t a process that I found easy, though enjoyable and satisfying!

Mainly, I couldn’t ever seem to get the orientation the same as the samples given. This should theoretically be possible so I may be being an idiot, but I tried all options, and often confused myself doing so. In any case, none of my exposures corresponded exactly withthe example.

Obviously patterns of stars are more or less obvious depending on exposures, but can be strangely elusive when the orientation is different. I found it easier to use stars positioned very close together as initial reference points on my exposure when comparing to the example.

Also inverting the image I found helpful depending on the exposure.

Not sure if any of this is useful. Apologies if not and happy hunting! It’s very satisfying when it all falls into place.

Picture of Alan Cayless

Alan Cayless Post 17 (unread) in reply to 15

21 Jan 2021, 16:53 Edited by the author on 21 Jan 2021, 16:55

Hi Graham;

Thanks for having a go at the variable star, and that's great that you've got some images back.  As James has mentioned, the images may be rotated compared to the finder chart, and inverting them might help.

Another thing to be aware of is that the finder charts cover a slightly larger field of view than the COAST images, so maybe try concentrating on matching your images with the central portion of the finder chart.  There's an example here:

If you still can't get it to match up, let me know the image number and I'll check it out.


Picture of Graham Womack

Graham Womack Post 18 (unread) in reply to 17

23 Jan 2021, 09:16

Hi Alan,

Thanks for your response. I'd already tried inverting the images - both vertically and horizontally, without success,

The image numbers are: J369723, J369724, J369411& J369715 

All of these were requested for the same co-ordinates, with different exposure times.

Thanks in advance


Picture of Alan Cayless

Alan Cayless Post 20 (unread) in reply to 18

23 Jan 2021, 17:03 Edited by the author on 23 Jan 2021, 17:05

Hi Graham;

Thank you for the image numbers - this has really helped.

The first three images are of the correct field of view.  

The coordinates of J369715 are different - it looks as though this one is part of the Beehive cluster (M44).  You may have noticed that it comes up as "unknown" in the photometry tool.  Sho you can exclude this one.

The others are of the correct star field.  The next thing to notice is that the second two (J369724, J369411) are rotated 180 degrees compared to the finder chart, and J369723 is the same orientation as the chart. This is because of the pier flip - the first two were taken earlier in the night of the 17th / 18th Jan, and J369723 was taken several hours later (05:36 in the morning) after the star had crossed the meridian.

The last thing that will help matching the images up is that the target star is centred in your image, but slightly off-centre in the finder chart.  As with the other ones, the finder chart covers a slightly wider field of view than the COAST image.

Here is a marked up version of the finder with an outline showing the field of view of your image J369723.  Have another go at matching these up - once you've found the target and reference, you'll be able to easily identify them in the rotated images as well.


Picture of Graham Womack

Graham Womack Post 21 (unread) in reply to 20

24 Jan 2021, 13:59

Hi Alan,

Thanks for your help with this. Actually I provided the wrong reference for J369715 - should have been J369725. This was for identical co-ordinates as the other three, and once I'd flipped the image (both axes) I've been able to plot the result.

Thanks again


Picture of robert hammond

robert hammond Post 19 (unread) in reply to 15

23 Jan 2021, 14:36

Hi Graham,

I too have had great problems finding the targets and references.

My method is as follows:

Download the image .png file with the highest exposure to your computer and edit it/invert it as you want. Print it, find and mark the target and reference.  You are then confident that you, at least have the correct stars on there somewhere.

Then go to FITS Photometry, load the fits file and find the corresponding stars there. I find this a bit operation more difficult as the orientations may need adjusting. But I KNOW the stars are there somewhere.



Take your learning further371

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses372.

If you are new to university level study, we offer two introductory routes to our qualifications. Find out Where to take your learning next?373 You could either choose to start with an Access courses374or an open box module, which allows you to count your previous learning towards an Open University qualification.

Not ready for University study then browse over 1000 free courses on OpenLearn375 and sign up to our newsletter376 to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371