Date: 2 March 2022
Location: Bethesda
🌦💧☀🌈🌈
Category Archives: Optical Phenomena
Optics Picture of the Day
Interference patterns in matcha tea bubbles – featured in Optics Picture of the Day 25 January 2021
Matcha tea posts on LustreBox
Solar Halo
22° halo
Date
31 July 2020
Location
Bethesda, Wales
Information
Further Reading
Lunar Halo
Lunar Halo
Date
5 March 2020
Location
Bethesda
Information
Further Reading
Solar halos (Carneddau);
Other optical phenomena posts;
22° halo (Wikipedia)
Llanfairfechan
Llanfairfechan beach, looking towards Anglesey (left) and Puffin Island (centre), with a faint auroral glow above the horizon
Date
7 November 2017
Location
Llanfairfechan
SH 67906 75446; 53.25950°N, 3.98171°W
Information
Newborough Forest
Newborough Forest
Date
17 July 2016
Location
Newborough Forest, Anglesey
SH 41320 63620; 53.14601°N, 4.37405°W
Light Ring
Light Ring, Information Board on Malltraeth Cob
Date
3 July 2015
Location
Malltraeth, Anglesey
SH 40836 68453; 53.18927°N, 4.38369°W
Information
The light rings were observed on the perspex cover of the information panel on Malltraeth Cob.
The image has been featured on the Optics Picture of the Day site, which gives an explanation of the optical phenomena behind the effect.
Further Reading
Scratched perspex, light rings and diffraction (Atmospheric Optics);
Malltraeth Cob
Carneddau Rainbows
Primary and secondary rainbows. Looking towards the Carneddau mountains.
| Date | 7 June 2014 | ||
| Location | Bethesda | SH 63395 66545; 53.17841°N, 4.04548°W | |
|
Information |
|
||
Moel y Ci Rainbow
Looking towards Moel Wnion from Moel y Ci
| Date | 12 August 2013 | ||
| Location | Parc y Bwlch, Moel y Ci | SH 59382 66403; 53.17608°N, 4.10541°W | |
Montaña de Arena, Fuerteventura
Looking towards Montaña de la Blanca from the summit of Montaña de Arena. The apparently converging ‘anti-crepuscular rays’ are formed by shadows being cast by clouds on the opposite side of the sky.
| Date | 3 April 2013 | ||
| Location | La Oliva, Fuerteventura | 28.633835°N, 13.929066°W | |
|
Information |
Created 185,000 years ago, Montaña de Arena (422m) was declared a Natural Monument in 1994. The mountain is located 2.5km north of La Oliva in northern Fuerteventura, and its volcanic ‘bad lands’ plain, the Malpaís de la Arena, stretches some 6km from La Oliva northwards to Lajares. There are two conjoined craters at the top of the volcano’s pyroclastic cone, which stands 120m above the base of the mountain.
|
||
Holyhead Breakwater
At 1.7 miles long, Holyhead Breakwater, completed in 1873, is the longest in the UK.
| Date | 17 June 2012 | ||
| Location | Holyhead, Anglesey | SH 25661 84774; 53.33106°N, 4.61950°W | |
|
Information |
Holyhead’s role as a port for mail-packet crossings to Ireland dates back to the 16th century, but it was in the 19th century that major changes were made as part of a programme of improvements to the mail route from London to Dublin. A new harbour of refuge, where boats could shelter in bad weather, was created when a long breakwater was built off Soldiers Point. Construction began in 1845 and was completed in 1873, with the work initially supervised by James Meadows Rendel and after Rendel’s death in 1856, by John Hawkshaw. The mock castle at Soldiers Point was built in 1848 as the Superintendent Engineer’s residence. The 19m-high lighthouse at the end of the breakwater, with its unusual square tower, was probably designed by Hawkshaw and was completed in 1873. It is operated by Trinity House and was automated in 1961. At 1.7 miles long, the breakwater is the longest in the UK. Seven million tons of quartzite extracted from the quarries on Holyhead Mountain were used in its construction. In August 2011 the breakwater’s owners, Stena Line, were criticised for their lack of maintenance of the structure. The issue of its proper upkeep has been linked to Conygar Stena’s Holyhead waterfront development plans. Holyhead Breakwater (Royal Commission on the Ancient and Historical Monuments of Wales); |
||
Carneddau Halos
Solar halos over Carnedd Llewelyn and Yr Elen
| Date | 28 January 2012 | ||
| Location | Carnedd Gwenllian, Carneddau | SH 68520 66535; 53.17961°N, 3.96883°W | |
|
Information |
This impressive display of atmospheric optical phenomena – caused by ice crystals in high cirriform clouds refracting and reflecting the light from the sun – was witnessed around 2pm on 28 January 2012. It was viewed from a spot on the slopes of Carnedd Gwenllian (formerly known as Garnedd Uchaf) looking south over Carnedd Llewelyn and Yr Elen in the Carneddau range of mountains in North Wales. The various components of the display are described below. |
||
Individual components of the optical display
|
Circumzenithal Arc Supralateral Arc Upper Tangent Arc 22° Halo Parhelion Parhelic Circle Paranthelion Warning: when looking for solar halos, never look directly at the sun. (Featured in Atmospheric Optics Picture of the Day)
|
Sun dog over Moel y Ci (‘Dog Hill’) (2)
Sun dog over Moel y Ci
| Date | 5 August 2011 | ||
| Location | Viewed from Bethesda, Wales | SH 63219 66497; 53.17793°N, 4.04809°W | |
|
Information |
A sun dog (or parhelion) is a luminous spot on one or both sides of the sun at the same height as the sun. It is formed by refraction through hexagonal plate crystals of ice in high cirrus clouds.
Featured in NASA Earth Science Division’s Earth Science Picture of the Day, 12 October 2011. Sun dog over Moel y Ci (‘Dog Hill’), 1 September 2010 |
||
Moon, Jupiter and Lunar Halo
Moon, Jupiter, Lunar Halo
| Date | 13 December 2010 | ||
| Viewed from | Bethesda | SH 63218 66487; 53.17784°N, 4.04811°W | |
Heiligenschein
Heiligenschein
| Date | 4 October 2010 | ||
| Location | Parc Menai, Bangor | SH 54080 69938 | 53.20640°N, 4.18631°W |
|
Further Information |
The Heiligenschein (Holy light) is a bright patch around the shadow of the oberserver’s head. It is caused by dew drops on the grass roughly focusing the sun’s light onto the blades. Some of the light scattered from these bright spots is then returned through the drops back towards the observer. Heiligenschein mechanism (Atmospheric Optics)
|
||
Sun dog over Moel y Ci (‘Dog Hill’)
Sun dog over Moel y Ci
| Date | 1 September 2010 | ||
| Location | Viewed from Bethesda, Wales | SH 63219 66497 | 53.17793°N, 4.04809°W |
| Further Information |
A sun dog (or parhelion) is a luminous spot on one or both sides of the sun at the same height as the sun. It is formed by refraction through hexagonal plate crystals of ice in high cirrus clouds.
Sundogs, Parhelia, Mock Suns (Atmospheric Optics) |
||
Solar Halos, Bangor
9° and 22° halos seen from Bangor, N Wales
| Date | 13 July 2010 | ||
| Location | Parc Menai, Bangor, Wales | SH 54053 69911 | 53.206158°N, 4.186692°W |
| Further Information |
9° circular halo (Atmospheric Optics); 22° circular halo (Atmospheric Optics)
(Featured in Atmospheric Optics Picture of the Day) |
||
Tryfan
Rainbow over Llyn Ogwen from Tryfan
| Date | 10 July 2010 | ||
| Location | Tryfan, Glyderau | SH 66632 59967 | 53.12014°N, 3.99433°W |
Snowdon Brocken Spectre
Brocken Spectre near the summit of Snowdon
| Date | 12 June 2010 | ||
| Location | Close to Snowdon Summit | SH 60898 54282 | 53.06760°N, 4.07749°W |
| Further Information |
Atmospheric Optics; Wikipedia
(Featured in Atmospheric Optics Picture of the Day) |
||
GeoTopoi 