Next Talk

Please note that all talks until at least July 2021 will be held on the Zoom video conferencing platform. Invitations to Zoom talks are sent to CAS members shortly in advance. Members planning to watch a talk should try to enter the Society's Zoom "Waiting Room" before 7.30 p.m., as late entry may be distracting for everyone.
The resumption of talks within a lecture theatre environment will be clearly announced.

Thursday 18th March 2021 at 7.30 p.m. "ARIEL and ALIEN Worlds: Enabling planetary science across light-years" presented by Dr Chris Pearson, Rutherford Appleton Laboratory - STFC

Less than 30 years ago the only planets known to exist were those found within our own Solar System. From the first confirmed discovery in 1992 - of a pair of exotic planets orbiting around a dead star - the field of exoplanetary science has undergone nothing short of a revolution. Currently we stand at a staggering 4000+ confirmed discoveries of planets outside our Solar System. What we have found is that, as usual, our Universe is more diverse that we could possibly imagine, throwing up a menagerie of weird and wonderful planets such as Jupiter sized worlds orbiting ridiculously close to their parent stars, worlds made of ice, lave and even diamond, to rogue planets drifting alone in the vastness of space. With such a treasure trove of discovery, the next logical step is to characterise the properties of these systems. We are at the dawn of a new age in exoplanet research where for the first-time large samples of 1000+ exoplanets are not only being detected but also characterised by analysing the composition of their atmospheres. The European Space Agency's ARIEL mission, due for launch in 2028, will become the leading facility in this characterisation process.

Dr Pearson's PhD was in "Galaxy Evolution and Cosmology" with Professor Michael Rowan-Robinson Imperial College, London. Since then, Chris has worked on cosmological galaxy surveys at infrared wavelengths for both ground based telescopes and space borne missions. He worked for 7 years in Japan on the AKARI space telescope before moving to the UK to RAL Space to work on the SPIRE instrument on the Herschel Space Observatory where he leads the team that produced all the nice maps from SPIRE. Chris now works on the ARIEL mission searching for exoplanets and the Square Kilometre Array radio telescope, the largest scientific facility ever to be built.


The Society's activities during the coronavirus (COVID-19) pandemic


During the coronavirus crisis the Society wishes to ensure that the risks to CAS members and the wider public are minimised. Accordingly, please note that:

  • we currently expect that all the fortnightly talks in the 2020/21 season will need to be held using the Zoom video conferencing platform (see the guidance below); and
  • no CAS Star Parties at our Observatory at Dyffryn Gardens are currently planned, and the Observatory is closed until further notice.

We will keep members updated on future developments via this website and other suitable means. We hope everyone stays well during the crisis.

GUIDANCE ON ZOOM: See this short video on how to join a Zoom meeting and this specific CAS guidance

The Science of Vision: an interactive fun event discovering the link between science and vision 12th March 2021, 10.00am - 1.00pm Zoom

The event aims to reach out to members of black and minority ethnic communities and those with sight loss. These communities are currently under represented in the field of Vision Science and Science generally. This event will aim to engage those who are currently not engaged in science, and provide further understanding of the link between science and vision.

Our chairman, Phill Wallace, is involved with the project and will be running a workshop and be part of a panel answering questions.

For more information contact Esther at or telephone 01495 763650


National Museum of Wales: Amazing Astronomy. A weekend of free, online events on 20th and 21st March 2021

At spring equinox, let our team of experts and fun presenters inspire you about all things astronomical, and guide you in an exploration of the night sky.

  • Science shows the whole family will enjoy
  • Cosmic crafts
  • Behind the scenes tour of the Museum's meteorite collections
  • Live Q & A with Museum curators
  • Solar System Quiz
  • Tour of the Stars
  • And for a stellar ending to the weekend, TV presenter and British Astronomer, Mark Thompson, will present a live show and Q & A. So, get ready with all your burning astronomy questions.

For further information and to book events see here


FAS Dark Skies Position Statement

Please click on the button to the right to download the recently issued statement from the Federation of Astronomical Societies regarding their views on dark skies and light pollution.

The statement mentions two other sources of information

  • Information on the All-Party Parliamentary Group for Dark Skies 2020 policy paper on Ten Dark Sky policies for the government can be found here
  • Information on the model followed by the UK Dark Skies Matter initiative can be found here

CAS Social on Tuesday Evenings via Zoom (Members Only)

Every Tuesday evening from 7pm to around 8:30 we hold a social get together on zoom where we chat about both astronomical and non-astronomical subjects, have a quiz and have presentations by members. These presentations are usually on either member's hobbies or their travels but can be on anything they think others will find interesting.
Why not come along one week to see what you think. You do not need to stay for the whole session and people often arrive late or leave early because of other commitments. It is very informal!
To register your interest email please include your Membership Number and you will be sent a link to the next session.

Possible things to do during the lockdown or in self-isolation

  • Listen to this Radio 4 programme on Gravity with Hannah Fry and Adam Rutherford See here. BBC Sounds podcast here. Also on Acast and probably iTunes.
  • Listen to the talks run by Palomar Observatory See here. The times given are Pacific Time but you can view the talks at any point afterwards on YouTube.
  • Listen to The Infinite Monkey Cage Podcast. A recent episode is on The Night Sky and Tim Peake is a guest. Listen here
  • Enrol on one of the free talks being run by The Geological Society of London about the Geology of Space. For more details see here
  • Book tickets for free, online Astronomy talks being run by Royal Observatory Edinburgh. See here
  • Catch the very latest astronomy news from See here
  • Buy the recently published book The Search for Life on Mars: The Greatest Scientific Detective Story of All Time by Elizabeth Howell and Nicholas Booth - see here
  • Watch video: 10 Unsettling Astronomical Incidents and Phenomena - see here
  • Watch the eighth series of How the Universe Works on the Discovery Channel - now being rebroadcast. Series 1 to 7 also available
  • Watch a video of a talk given to the Society for Popular Astronomy - this 77 minutes talk, being shown with the kind permission of the SPA, is by Dr Rene Breton and is entitled Einstein's Relativity: Tested to the Limit with Pulsars
  • Join the Virtual Astronomy Club
  • NASA At Home provide a range of activities - details here. Or watch NASA TV
  • Astronomy Citizen Science Projects - see here
  • The Sky at Night - and watch old and not-so-old episodes on the BBC iPlayer including the 800th episode shown on BBC4 on 10th May 2020!
  • Astrophotography with only a DSLR camera or a smartphone - see here and also here
  • Podcasts - for instance, the BBC Sounds podcast includes The Life Scientific series which features a number of astronomy-related sessions including an interesting interview with Dame Jocelyn Bell Burnell who, scandalously, was not awarded a Nobel Prize after her discovery of radio pulsars
  • Fine-tune and clean your astronomy equipment - guidance is available on the internet including in the BBC's online Sky at Night magazine

The night sky this month

(Courtesy of BBC Sky at Night Magazine)

Day-by-day guide to this month's night sky

- text and photos


Next Star Party



Next Observing Session




Black Lives Matter in Astronomy

See this update from the Royal Astronomical Society



Introduction to CAS

The Cardiff Astronomical Society (CAS) is a thriving society located in South East Wales. It has been in existence for over 40 years and is one of the largest amateur astronomical societies in the UK. CAS provides a range of facilities for both Society members and the public at large including a varied programme of talks on Thursday evenings (except in August) at the Physics and Astronomy Department of Cardiff University. In addition, regular night sky (and occasional solar) Observing Sessions are held at the Society's own Observatory at Dyffryn Gardens.

Our members come from all walks of life and their knowledge of astronomy ranges from complete beginner to advanced. You don't need any specialist knowledge to join us and neither do you need to own a telescope or binoculars. It's also possible to try us out before joining!

More details about the Society and what it does are available here

We are keen to get more Society members on board to assist with the running of CAS events - please see here how you can Help Us

Society help for schools etc



As shown here, Cardiff Astronomical Society welcomes all invitations from organisations such as colleges, schools and guide/scout/brownie groups located in Cardiff and surrounding areas for an outreach stargazing/astronomical event for all ages and levels of knowledge. Society members very much enjoy bringing our passion for the subject to a wider audience and helping everyone to get started in this fascinating subject. We do not charge a fee for our expertise and participation; the enjoyment is enough reward and we will do our very best to ensure a worthwhile and enthralling evening. We would, however, be grateful for reimbursement of travelling expenses and petrol costs to venues outside of Cardiff and its environs. Otherwise the cost would fall on individuals and the non-profit-making Society. It should be noted that CAS has a formal Policy on Child Protection and the Protection of Vulnerable Adults


Join the Society

Come and join some of the Society's 275 members at one of our talks or observing events. We promise a warm and friendly welcome for all. Only £15.00 per annum also means you can make use of our Library

Gift Aid

CAS is registered for Gift Aid. This means that, if you are a UK taxpayer, we can claim back the standard rate tax on subscriptions (and on any donations) giving an effective 25% boost to the amount the Society has received. However, in order to reclaim these monies from HMRC, we need all members who pay tax to complete and return a Charity Gift Aid Declaration form. Please note that if you have paid your subscriptions by PayPal, you will have already been asked if you would consent to those subscriptions being Gift Aided - but we still need a completed Charity Gift Aid Declaration form in order for us to reclaim the tax paid as Gift Aid.

If you are eligible, please take a form (using the button opposite) and then complete it and pass it to us at one of the fortnightly talks or send it to CAS by post or email (see the bottom of the form). Thank you for your help!

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