Observing Sessions

Members of the public are welcome. Come and see the wonders of the Universe through our telescopes and talk to knowledgeable astronomers. It's a whole new experience just waiting for you to enjoy!

When and where do they take place?

We aim to hold two observing nights in each calendar month and we try to determine two pairs of weekend nights (two Friday nights and the immediately following Saturday nights) when the night sky is, subject to weather conditions, likely to be at its darkest. This means that if the skies are clear on one of the Friday nights the observing session will take place that night but if the skies are overcast on the Friday we will try again on the next (Saturday) night. With luck, this will mean that an observing session will be held on each of the two scheduled weekends. However, in some months it will be possible to meet on only one of the planned nights or, more rarely, on none of them.

The dates of the planned sessions are published in the CAS Newsletter and also below where you can also check whether a planned observing session is to take place.

At the moment our observing nights are held at the Society's own Observatory at Dyffryn Gardens. You can find a map and directions by clicking here.

Observing Sessions 2017-18

Date Day Time Venue Status
27th October Friday 20:00 - 00 Dyffryn Gardens Tonight's session will go ahead
17th November Friday (no Saturday session as this would clash with the St Fagans stargazing event) 20:00 - 00:00 Dyffryn Gardens Tonight's session Fri, 17th is cancelled due to overcast conditions
24th or 25th November Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
15th or 16th December Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
2018
12th or 13th January Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
19th or 20th January Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
9th or 10th February Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
16th or 17th February Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
16th or 17th March Friday or Saturday 20;00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
23rd or 24th March Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
13th or 14th April Friday or Saturday 20:30 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
20th or 21st April Friday or Saturday 20:30 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
11th or 12th May Friday or Saturday 21:00 - 00:00 Dyfryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
7th or 8th September Friday or Saturday 20:30 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
14th or 15th September Friday or Saturday 20:30 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
5th or 6th October Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
12th or 13th October Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
2nd or 3rd November Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
9th or 10th November Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
7th or 8th December Friday or Saturday 20:00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead
14th or 15th December Friday or Saturday 20;00 - 00:00 Dyffryn Gardens Phone 07535 718669 to see if either of these sessions will go ahead

How do I know if the session is on or not?

Generally, if it's completely cloudy then the session will not take place. For the latest information for the next session, either check the right-hand column of the above timetable or phone the CAS Observing line on 07535 718669

Do I need to have a telescope to come to an observing evening?

No. We always stress that you don't need a telescope to look at the night sky and we have a small supply of binoculars for attendees to borrow. Our aim is for observing evenings to be a social event and a chance for people to discuss astronomy and learn from each other. If you haven't got a telescope there will be plenty of people who have got one and will be only too happy to let you use theirs.

Observing using a telescope

Please ask before you touch someone else's telescope. Set-ups can be different for each scope, and they may be in the middle of taking a photograph or something, even if it looks as if no-one is using the scope. If you do have a telescope but haven't had much success using it, don't be afraid to bring it along. You'd be surprised how many people struggle to find objects in their new telescope - you would not be alone. Bring it along and someone will be happy to give you advice on setting it up, and finding your way around with it.

What should I wear?

The main essentials are warm clothing - and perhaps also bring a warm drink and something to eat. No matter how warm it may have been during the day and what the weather forecast says, if you are stood under a clear dark sky for several hours it will be COLD and we don't want any hypothermia cases on our hands! It will also be dark, so you may be tempted to bring a torch. If you do, please make sure it gives out only a red light. It takes about 20-30 minutes for the human eye to become 'dark adapted' for optimum night viewing, and a white light will cause you (and others) to lose that dark adaptation. Using a red light avoids that, while allowing you to avoid obstacles and to read star charts etc. You can buy special red light torches, but you can just cover a standard torch with some red plastic and tape it on to get the same effect.

How long do observing sessions last?

This all depends on the weather and, perhaps most importantly, how cold it is! Normally, people start to drift away after 2 to 3 hours and only a few hardy souls make it past midnight. On a particularly clear night with plenty to see things may carry on into the small hours, but don't feel obliged to stay to the end if you'd rather be in bed.

I'm a complete beginner. What do I need to know before I come along?

There is no 'required level'. There will always be more experienced people who you can learn from, and you probably know more than you think anyway. It really is just a case of turning up, introducing yourself, and enjoying the view.

Etiquette for observing evenings

We don't have strict rules for observing sessions and keep things very informal. However, a few common sense points of etiquette will help things run smoothly:

  • Ask before you use someone someone else's telescope
  • Don't shine bright lights around where people are observing
  • If you are arriving late or leaving early, try to avoid car headlight beams shining where people are observing
  • Do not smoke near the telescope - smoke particles damage the optics.

Safety tips

Astronomy is not a dangerous pastime, but there are a few things to remember: It will be dark at the site and there will be plenty of things to trip over such as telescope tripods, cables, storage boxes, carrying cases etc. Take care to avoid obstacles and try to leave space between telescope set-ups, if you can. It will be cold. Make sure you dress appropriately. If you are unsure about anything, just ask. There are plenty of people there to help.

Please note that all private equipment brought to CAS events is not insured by CAS and therefore CAS will not be held liable for any damage or loss. The owner of the instrument is responsible for its safe and proper use at all times in accordance with the manufacturer's instructions.

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