Atmospheric Optics

A great example of a fogbow captured by member Kevin Smith on the 7th May 2023.

A fogbow is a similar phenomenon to a rainbow but as its name suggests, it appears as a bow in fog rather than rain. 

Due to the very small size of the water droplets that cause fog being so much smaller than in rain i.e. smaller than 0.1 mm in diameter; fogbows have very weak colours or no colour at all.  Fogbows that have no colour are sometimes called ‘white rainbows’.

A Fog Bow by Kevin Smith

NEVER LOOK AT THE SUN DIRECTLY. Please see our Solar Observing safety page at crayfordmanorastro.com/solar-safety/

A splendid example of a Sun halo captured by CMHASD Chairman John Archer on the 30th April 2023.

A Sun halo is caused by the refraction, reflection, and dispersion of light through ice particles suspended within thin, wispy, high altitude cirrus or cirrostratus clouds.

CMHASD member Jim Burchell captured this superb Sun Halo on the 14th Dec 2022 around midday which lasted for quite a long time – over an hour. A Sun halo, also known as ’22 degree halo’, is an optical atmospheric phenomenon that occurs due to sunlight refracting in millions of hexagonal ice crystals suspended in the atmosphere. 

More information about how Sun Halo’s are formed can be found on the Atmospheric Optics website.

A shinning example of a Sundog captured by member Martin Crow when out and about on the 20th Nov 2022.

A Sundog (or sun dog) is an optical atmospheric phenomenon that causes a bright, rainbow-colored patch of light to occur on either side of the sun or both sides at an angle of 22 degrees.  Sun dogs occur as a result of the refraction or scattering of light from flat hexagonal-shaped ice crystals that are suspended in clouds.

In the most brilliant displays, when 2 Sundogs appear, it’s as if there are now three suns in the sky — the main sun and two little siblings.

These “side suns” are colloquially known as sun dogs, officially known as “parhelia,” which is Greek for “next to the sun.”

CMHASD Chairman John Archer captured a beautiful sunrise on the morning of the 12th October 2022 along with an atmospheric phenomenon called a ‘sun pillar’ albeit a small one. 

‘A sun pillar is a vertical streak of light that appears above or below a low Sun that is shining through ice-crystal clouds, such as Cirrus, Cirrostratus and Cirrocumulus, or the ground-level ice-crystal fog, diamond dust.’ https://cloudappreciationsociety.org/cloud-library/sun-pillar/

They can be 5 to 10 degrees tall and sometimes even higher. They might lengthen or brighten as you gaze at them.

OK so it is the NLC season but WOW another sighting of these rare clouds by members.  A very bright & beautiful display it was too that lasted again for quite a while into dawn until 4.15am. 

An alert went out at 2.33am from member Sonia as she had spotted them very low down in the North East.  Two members; Diane Clarke and Jim Burchell picked up the alert and so joined Sonia in photographing the beautiful display that was to follow.  All photos where taken from various locations in North Kent by the members.

Below are 4 images by Jim Burchell taken at around 3:30 am. All image’s were taken with a Pentax K70 and there has been no processing.

Below are 2 images taken by member Diane Clarke.

Panoramic view of the NLC.  Diane wrote ”It went on to develop enabling me to capture 6 separate images taken at 03.30hrs that I used to create this panorama encompassing the splendour of this NLC.”

NLC at 4am as it began to fade in the North West.

Below are some images taken by Sonia using an iPhone. Also seen & photographed that morning were the planets Mars, Jupiter and Saturn, the Moon and a very curious fox who kept watch on Sonia whilst she took her photos.

NLC and the star Capella at 2.41am.

NLC developing nicely at 3.03am.

NLC at 3.10am – more finer detail emerging.

NLC at 3.21am.

NLC at 3.22am. You can see how bright they were next to a street light.

NLC at 3.38am. The NLC moved from the North East to the North West as dawn approached.

Another sighting of Noctilucent Cloud or night shining cloud by member Sonia on the 12th July 2022.  Photos taken using an iPhone. Looking North East.

NLC at 3.27am

NLC at 3.32am

Member Stephen Cohen spotted something quite rare in the sky at midday on the 11th July 2022 over Cumbria – A  22° Solar Halo with an added Circumscribed Halo around that. Unusual to see in the UK so well spotted Stephen!

Well what a sight! Four planets, the ISS and Noctilucent Cloud that just kept giving…….

At 2.32am an alert went out to members via WhatsApp from member Sonia who had spotted the NLC developing in the North East.

Several members picked up the alert and so too got to witness & photograph a fantastic NLC spectacle which lasted a long time into dawn.  The last photograph taken was at 4.05am!  The planets Venus, Mars, Jupiter & Saturn (which was in the South) where photographed with the NLC too. Then starting at 3.08am there was a bright ISS pass overhead.

Spaceweather.com wrote ”This morning, sky watchers in Europe woke up to some of the brightest noctilucent clouds (NLCs) in years. The clouds were amazingly bright and remained very evident deep into dawn.  The clouds didn’t stop there. They spread south across Europe, backlighting the Eiffel Tower and completely filling skies in places where, normally, NLCs are confined to a thin band near the horizon.’‘

Below are a selection of stunning photos taken by members , Honor Wheeler, Jim Burchell, Diane Clarke, John Howarth and Sonia – all from North West Kent.

Four images of the NLC on the 6th July 2022 taken by Honor Wheeler.

Three images of the NLC on the 6th July 2022 taken by Jim Burchell.

NLC with Venus at 3.30am

NLC at 3.45am

Three images of the NLC on the 6th July 2022 taken by Diane Clarke.

Diane said ‘Again following  a message from fellow member Sonia, I set up my equipment and watched in fervent hope that the NLC would develop, as there is always the possibility that they will dissipate shortly after becoming visible.

The 1st image is a panorama created from 6 frames as the entire NLC was spread out over a large portion of the N-NE sky, that a panoramic view was the only option to encompass the majestic splendour on display.

Images by taken by Sonia using an iPhone of the NLC, ISS and Planets on 6th July 2022.

NLC developing in the North East at 2.46am. You can also see the star Capella.

NLC at 2.56am. Getting brighter & higher.

NLC at 3.03am with Capella.

The ISS appearing in the West at 3.08am.

NLC continuing to develop and spread with Capella at 3.15am.

NLC at 3.24am

NLC at 3.26am

NLC and Mars in the East at 3.36am.

NLC with Mars & Jupiter in the East at 3.42am.

NLC at 3.45am nearly overhead.

NLC directly overhead at 3.48am.

NLC at 3.49am spreading overhead.  Saturn can be seen bottom right in the image, which was in the South.

Well they just keep coming – more NLC albeit very faint spotted at 3am on the 8th July 2022 by member Honor Wheeler who sent the alert out to members.  As the NLC were faint to the naked eye members were willing them to get bigger and brighter but alas just a small patch is all that developed that morning.

Below are a selection of photos taken by members who responded to the alert.  All photos taken from North West Kent.

NLC by Honor Wheeler – The faint NLC are middle left.

NLC by Jim Burchell taken with a Pentax K70 – The faint NLC are middle left. 

NLC by Jim Burchell – The NLC are centre left in this image.

NLC by Diane Clarke

NLC at 3.30am.  A white whispy patch of NLC can just be seen in the centre of the photo. They are 7 O’Clock from the star Capella which is in the photo. Photo taken using an iPhone by member Sonia.