Astronomy Every Thursday…



Come and join CMHASD stargazing at Hall Place, Bexley – Wednesday, 14th February 2024 from 7pm.

Stargazing at Hall Place with CMHASD on the 14th February 2024.  Tickets can be purchased at: https://www.hallplace.org.uk/event/stargazing-february-2024/.

We will be there from 7pm to 9pm. (Doors open from 6.45pm)

Outdoor activities are weather dependant.

Advance booking required.

Please note this is a ticket only event organised by Bexley Council.

Below is a selection of CMHASD photos from our Stargazing event at Hall Place held last year.

Face-to-Face Meetings Every Thursday

Face to face meetings every Thursday plus we are live on Zoom*

As a courtesy to others please stay at home  and attend via the zoom if  you are feeling unwell – coughs, sniffs and sneezes etc.

* zoom will only be available with the lecturer’s consent.


A selection of images, photos and observations taken by CMHASD members


Society News

Autumn Equinox Star Party – Kelling Heath, Norfolk – Oct 2023

Below is a brief summary of the latest trip by CMHASD members to Kelling Heath for the Autumn Equinox Star Party written by Simon Dawes.

”10 Members, 5 pitches, 2 tents, 2 caravans, 1 camper van and a lodge set the scene for a damp and windy long weekend.

If you decided to go to the Autumn Kelling Heath star camp based on the weather forecast, you would never leave Crayford; fortunately us seasoned star campers know better than to believe the forecast.

Wednesday: Cloud, Wind and Rain.

Four of us arrived in the rain, setting-up camp in a brief gap in the weather and headed to Honor’s lodge for a very welcome evening meal.

Thursday: Cloud, Wind and Rain.

Some of us headed out for a walk to the beach stopping for tea and cakes at the village cafe, a cloudy night saved by us zooming into the Barry Kellet lecture.

Friday: Cloudy, Windy, and a clear night.

The short term forecast suggested a clear night, the clouds parted early and we weren’t disappointed, we had views through Dominique’s a very nicely set-up 3” Refactor, Keith’s 10” Dobsonian, Simon’s 12” Dobsonian, Julian’s 20” Dobsonian, and some very nice 4” Binoculars from a nearby pitch. 

It was too windy for imaging early on but the wind died down and David did a good job imaging using a Samyang 130mm Lens on an HEQ5 mount – possibly overkill – but the results spoke for themselves.

We packed up at about 3:30 am.

The sky at Kelling by Kevin Smith

The Milky Way by Simon Dawes

Images below are by Martin Crow

Below are images by Jim Burchell. All images where taken with a Pentax KP attached to a Skywacher star adventurer.  All the images are single frame images.

Saturday: Dry, partial cloud during the day, mostly cloudy at night

We visited the trade stands, being careful to leave our wallets behind. Julian had some wonderful views of the Sun in his Ha telescope a modified PST.

Sunday: Dry

We packed up and headed home.”

Plus Kevin had a cute little visitor one night to his tent 🙂

Sundogs & 22-degree Halo by Jim Burchell

Fine examples of sundogs and part of a 22-degree halo captured by member Jim Buchell on the 25th September 2023 from Dartford.

”A sundog, also known as sun dog, mock sun or parhelion, consists of glowing spots around the sun. They are created by sunlight refracting off plate-shaped ice crystals in the cirrus clouds. Sundogs are some of the most frequently observed atmospheric optical phenomena and can be observed throughout the year and anywhere in the world. They are also associated with 22-degree halos.

Sundogs tend to be most visible when the Sun is close to the horizon. The part of a sundog closest to the Sun tends to be red in colour, while the areas further away from the Sun generally appear blue or green.” Ref:https://www.timeanddate.com/astronomy/optical-phenomenon.html

For more information about sundogs and 22-degree halo’s check out https://atoptics.co.uk/blog/sundogs-sun-dogs-parhelia-mock-suns/ and https://atoptics.co.uk/blog/22-halo-formation/

ExoClock Conference, Thessaloniki, Greece 2023

2023 October 21/22

Aristotle University of Thessaloniki, Greece 

3rd ExoClock Annual Meeting 

CMHASD trustees Martin Crow, Simon Dawes and Dr Mike Rushton attended the 3rd Annual Conference of ExoClock in Greece, a project to improve the ephemeris of exo-planet transits for the European Space Agencies, Aerial Mission, due to launch in 2029.

During the conference Martin and Simon were awarded ‘Silver Awards’ for reaching over 100 successful ExoClock observations. Congratulations Martin & Simon!


Below are 2 accounts of the trip written by Martin and Simon.

Martin wrote ”When this year’s annual meeting was announced and that it was going to be in Greece, it felt that it was important to attend in person. The previous in person meeting, the first one since lock down, had been held at UCL in London. Because the project is international the annual meetings are a rare opportunity to meet other like-minded observers who we only normally see over Zoom.  

Simon (who is also a regular contributor to ExoClock) and Mike (who is interested in the project and has done some transits with his EvScope) also come along. 

We flew out on the Thursday which give us a free day to explore Thessaloniki before the weekend meeting. Our hotel was well placed in the middle of Thessaloniki although it was on a busy road junction.  

I knew nothing of the place before we went. It is steeped in history and in cats. Yes cats. They were everywhere. 

The Museum of Archaeology showed off the amazing finds of stuff made in and around Thessaloniki generally between 2000 and 2400 years ago. Delicate pottery and intricate gold jewellery, which had only survived because they were grave goods, were on display. The workmanship was incredible.  

We also visited the White Tower (Middle Ages), the Rotunda (Roman) still with its domed roof and some of the massive city walls. 

The weather was warm and there were plenty of restaurants to choose from. We took advice from the locals and kept away from the main tourist drags. The food was good, not expensive, and the portions were large. What not to like – providing you are not a vegan or veggie – there was a lot of meat. 

The location of the meeting was just a 15-minute walk from the hotel. 

The Saturday meeting kicked off with an Introduction given by Anastasia Kokori from UCL and various talks followed about the science surrounding the Ariel space telescope, the evolution of hot Jupiter’s and the possible use of machine learning with charting exoplanets. 

After lunch there were more talks about Ariel and ExoClock. Following on from afternoon tea were more talks relating to the ExoClock project. Some were better than others. 

On Sunday the day started off with talks from students taking part in ExoClock and using its data. 

There were then two short talks given by amateur astronomers. One of them was me. The brief was to talk about our experience of being involved with the ExoClock project. I described when I had first got started and the positive and supportive aspects of the software and project in general. I finished by putting it all into context, that is to say, how it allows me as an amateur astronomer to contribute to an area that is a frontier of astronomical research. Awesome. 

After the coffee break there were some very interesting talks/discussions about the focus groups and, also, education outreach in schools. 

Finally, after lunch, there was more on the working groups some of which, I have to say, that I struggled to follow. Plus, it had been a long day!! 

What I liked about the talks was that they were not too long, mostly 20-minutes. This is a good length and kept my attention, any longer and I would be drifting off. I found most of the topics interesting with fresh information on top of what I already knew. 

All in all, a very worthwhile trip.” 

Simon wrote ”We arrived on Thursday evening, and after dinner at a traditional Greek Taverna (ταβέρνα in Greek) we headed back to the hotel for Tea, in time to ‘zoom in’ to the societies lecture by Paul Money on the Vikings on Mars.

The following day was dedicated to sightseeing, Thessaloniki Archaeological Museum, The Arch of Galerius, The Rotunda (also commissioned by Galerius in the 4th Century AD), The Water Front and the White Tower and finally the Roman wall. One day really wasn’t enough for the sights and sites and we only scratched the surface of what Thessaloniki has to offer.

The conference was over 2 days, most lectures being 30 minute in length and ranging from the easy to follow to the latest mathematical, statistical and AI techniques associated with the Aerial and related Space Missions. Including, in one of the talks, a description of 24hrs of wasted Hubble time due to inaccurate exo-planet transit timings, really bringing home the impact amateur astronomers can have in this field by improving these ephemeris. There were also many talks on how MSc students were using exoclock data (hopefully crediting the observers) to understand better the characteristics of these planetary systems.

Martin and I were both awarded ‘Silver Awards’ for reaching over 100 successful observations (which is approximately 1000 hours of observing and maybe 300 hours in processing when you also take into account the failures due to weather or equipment issues) by the Principle Investigator (Giovanna Tinetti) and the leader of the Exo-Clock programme (Anastasia Kokori).

We headed home on Monday morning.

For more information about the conference click here https://www.exoclock.space/annual_meetings

ExoPlanet transit of HAT-P-23b by Keith Rickard

One more for the ExoClock project – this one being the first for CMHASD trustee and treasurer Keith Rickard.  It is of Exoplanet HAT-P-23b in the constellation Delphinus.

”HAT-P-23 b is a gas giant exoplanet that orbits a G-type star. Its mass is 2.09 Jupiters, it takes 1.2 days to complete one orbit of its star, and is 0.0232 AU from its star. Its discovery was announced in 2010.” Ref:https://exoplanets.nasa.gov/exoplanet-catalog/1345/hat-p-23-b/

For more information about HAT-P-23b click here https://exoplanet.eu/catalog/hat_p_23_b–737/

Superb Sun Pillar imaged by John Archer

Whilst travelling early morning on a train to London, CMHASD Chairman John Archer saw this fine example of a sun pillar on the 23rd October 2023. 

”Sun pillars and light pillars are beams of light that extend vertically upward (or downward) from a bright light source, such as the sun or another bright light low on the horizon. They can be 5 to 10 degrees high and sometimes even higher. In fact, they might lengthen or brighten as you gaze at them.  They’re beautiful and wondrous. And they’re also the source of some UFO reports!

When is the best time to see them?

You’ll most often see sun pillars when the sun is low in the western sky before sunset, or low in the east just after the breaking of dawn. However, you might even see a sun pillar when the sun is below the horizon. On the other hand, you can see light pillars at any time of night.  They’re called sun pillars when the sun helps make them. But the moon or even streetlights can create this light phenomenon, too, in which case the name light pillar is more appropriate.” Ref:https://earthsky.org/earth/what-is-a-sun-pillar/

For more information about sun pillars see Les Cowley’s brilliant website Atmospheric Optics .

Comet C/2023 P1 (Nishimura) imaged by Martin Crow

C/2023 P1 (Nishimura) is a long-period comet discovered by Hideo Nishimura on 12 August 2023 and member Martin Crow imaged it on the 20th August 2023.  At the time of its discovery, the comet was in the constellation of Gemini and shining at magnitude +10.4.

Image details: 5x60sec exposures. 235mm diameter SCT @ f5.4, SX694 mono CCD.

ExoPlanet TrES-3b transit – observed by Simon Dawes

Another for the ExoClock project by Simon Dawes of the transit of exoplanet TrES-3b.

TrES-3b is in a very tight orbit around its host star, TrES-3, transiting the stellar disk once per 31 hours. For comparison, Mercury orbits the sun once every 88 days. TrES-3b is just a little larger than Jupiter, yet orbits around its parent star much closer than Mercury does, making it a “hot jupiter.”

The Milky Way by Honor Wheeler – Oct 2023

Four superb single shot images of the Milky Way captured by member Honor Wheeler whilst on holiday in Kelling Heath, Norfolk.  In one of the photo’s there is a meteor!

CMHASD supporting the BAA at New Scientist Live – ExCel London 2023

Crayford Manor House Astronomical Society Dartford (CMHASD) were out in force at the recent New Scientist Live event at ExCel Centre, London Docklands on the 7th to 9th October 2023.  We were there to help the British Astronomical Association (BAA) on their stand over the 3 days to promote the BAA and answer questions from members of the public, school children and teachers on all things astronomical.

CMHASD member Diane Clarke wrote ”As part of our display we had several 3D printed items which  included: M51, painted scale models of the planets Mars & Jupiter and a section of the largest canyon in the Solar System the Valles Marineris. 

Issac and Tinie the CMHASD Dobsonian telescopes were a favourite with all.  Visitors to the stand were able to look through Issac and Tinie at a 7m diameter inflated printed globe of the planet Mars.

All of these proved great talking points enabling us to make several sales as well as promoting membership of the BAA.

Among the visitors to the BAA’s stand was Professor Richard S. Ellis with his family; who had earlier in the day given a talk titled When galaxies were born: First results from the James Webb Space Telescope to a packed audience.

All in all, everybody who staffed the stand enjoyed the experience.  Over the 3 days their enthusiasm & knowledge radiated to everybody that visited the stand, hopefully resulting in future new members of the BAA.”

CMHASD would like to thank all their members who helped over the 3 days and to Diane Clarke for sharing her photos of the event.

CMHASD Solar Observing at Hall Place – 19th August 2023

NEVER LOOK AT THE SUN DIRECTLY. Please click here for solar observing safely.

On Saturday the 19th of August several members of the Society were present for the second of our 2 solar observing sessions at Hall Place & Gardens.  Below are some photos of the day.  Thank you to Dr Mike Rushton, Honor Wheeler, Jim Burchell, Omila and Diane Clarke for sharing your photos.

The Sun in Hydrogen Alpha taken by Honor Wheeler using a Personal Solar Telescope (PST).


The Sun in white light taken by Omila using an iPhone with an adapter and telescope fitted with a Solar filter.

Full Moon & the final Supermoon of 2023 – 29th Sept 2023

Several CMHASD members were out on the 29th September 2023 to image the final Supermoon of 2023 and below are their images.  This full Moon is also known as the Harvest Moon as it is the closest Full Moon to the September equinox this year. 

Most years, the Harvest Moon is in September but around every three years it’s in October.  When the Harvest Moon occurs in September it replaces the Corn Moon. When it happens in October it takes the place of the Hunters Moon.

Kevin Smith’s image taken from Deal, Kent.

Honor Wheeler’s images taken from Dartford, Kent.

Dominique Ferrand’s image taken from Cordoba, Spain.  Dominique’s image is of the full Moon and Jupiter.

For more information: https://www.timeanddate.com/astronomy/moon/harvest.html

Annular Solar Eclipse 2023 – Richard Bohner

NEVER LOOK AT THE SUN DIRECTLY. Please click here for solar observing safely.

On Saturday 14th October 2023 an annular solar eclipse crossed North, Central and South America.   

Member Richard Bohner; who lives in the USA wrote ”Hello all. There will be an annular solar eclipse here in Arizona on 14 October at 9:30 AM. The path is crossing the “Four Corners” area (where Utah, Colorado, Arizona, New Mexico come together). I am coming back from a week holiday in Colorado, but leaving early in morning (6 AM) to get to my spot to observe the eclipse at 8:30 AM. I will have photos to post.” and here they are…

Some info on eclipse –  Moon distance 246,504 miles and Moon coverage of sun 95.2%

Richard used his old Meade ETX 70 to acquire the photos.

The Sun and the Wilson Effect – Simon Dawes

NEVER LOOK AT THE SUN DIRECTLY. Please click here for solar observing safely.

On the 26th September 2023 member Simon Dawes imaged the Sun.  One of his images of the sunspots on the Sun that day showed an interesting effect called the ‘Wilson Effect’.  The Wilson effect is the perceived depression of a sunspot’s umbra or centre in the Sun’s photosphere.

Sunspot AR3443 showing the ‘Wilson Effect’


ExoPlanet transit of TrES-3b by Dr Mike Rushton

The transit of Exoplanet TrES-3b by CMHASD member & trustee Dr. Mike Rushton using an eVscope for the ExoClock project. TrES-3b is a gas giant exoplanet orbiting the star GSC 03089-00929 a G-type star and is 0.02282 AU from its star. It has an orbital period of...

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Crepuscular rays at the pavilion by Honor Wheeler

A lovely image taken by member Honor Wheeler on the 10th August 2023 whilst at the pavilion on an informal night of some crepuscular rays. ”Crepuscular rays are sunbeams that originate when the Sun is just above or below a layer of clouds, during the twilight...

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Moon & Jupiter by Diane Clarke

A lovely image of the Moon and Jupiter taken by member Diane Clarke. Diane wrote ” Jupiter & the Moon 4° apart.  I went to image this event as it rose above my local horizon, but the sky was cloudy so I decided to wait as both Jupiter & the Moon...

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Crescent Nebula by Kevin Langford

A stunning image of the Crescent Nebula taken by member Kevin Langford on the 5th Sept 2023. ”The Crescent Nebula (also known as NGC 6888, Caldwell 27, Sharpless 105) is an emission nebula in the constellation Cygnus, about...

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Informal Nights at the Society

A few photos showing what members get up to on our ‘informal nights’ at the Society.  Activities range from observing, testing/setting up members’ latest equipment purchased, fixing members’ equipment, presentations, general chit chat...

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Our Active Sun by Simon Dawes

More stunning images of our active Sun taken by member Simon Dawes in the later half of July 2023.  Details of how Simon acquired his images are on the photos. For more information about the Sun, its structure, atmosphere, sunspots, solar cycle and magnetosphere...

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