The National Park Dark Sky Festival for the Yorkshire Moors and Dales…
In the UK we’re getting more and more detached from what the nights sky looks like, we have a knowledge of some of the constellations and asterisms. Some know the plough and its use to find the pole star, many can find Orion during winter with his distinctive belt, but what the sky looked like to our ancestors and how it changed during the year indicating the coming of seasons is something we have lost, how the appearance of the Summer Triangle, made of the stars Vega, Altaire and Deneb and its significance relating to the return of the summer months.
The encroachment of light pollution has such a significant effect on how we live our lives, it makes us feel safe in dark cities, but nature of the design and shear number of unnecessary lights is drowning out the night. The Bortle scale is a measure of light pollution and what we should be able to see. The scale runs from Bortle 9 to 1. 1 being a perfect dark sky sight, the spiral arm of our galaxy, the Milky Way, should be able to cast a shadow on a moonless night all the way to Bortle 9, which would be equivalent to looking up at the sky in the middle of a major city.
You can judge the levels of light pollution in your local area by finding Orion the Hunter. Look south east from around 19:00, the later the better! Orion appears as a rectangle with three stars making up its belt. The top right star is Betelgeuse (the subject of our previous Blog!) the top right is called Bellatrix; the bottom line of the rectangle is Rigel and Saiph. Count the stars within the rectangle, you can include the belt and the rectangle forming stars. To see no more than 10 indicates you are in a heavily light polluted area. In a dark sky site, you expect to see thirty, a remarkable sight!
There are some amazing dark sky sites around the UK, the Brecon Beacons, the Lake District, Dartmoor, Kielder Forrest, Snowdonia and The Yorkshire Dales to name a few, they’re locations where we can get a feeling of what our night sky would have looked like in the past. To see a fuzzy band of stars which make up our own galaxy and then to look between Peruses and Cassiopeia to see a faint smudge, our nearest neighbour Andromeda.
The National Park Dark Sky Festival is an event that aims to claim back the night, to bring awareness of the level of light pollution. The festival begins on the first of February and runs through to the end of march is an amazing opportunity to reconnect with our ancestors and see the wonders of the universe, simple to observe the number of stars makes finding the constellations a challenge! For this Dark Sky Festival, we have teamed up with Go Stargazing and The Tan Hill Inn, the highest and best (probably) pub in the UK. A location where the aroura is visible! Go Stargazing and their astronomers aim is to make astronomy accessible for all. We’ll be at Tan Hill on for the week beginning the 17thof February and on Friday the 21stand 28thof Feb.
To combat light pollution, you can find different filters for your telescope or camera. It should be warned that these won’t make objects brighter, only increase the contrast between them and the sky! How filter work is…. our streetlights work via florescence, that is the gas is excited which emits photons of light of a very particular frequency. The Filters work by absorbing photons of a similar frequency thus removing the photons of light emitted from the fluorescence of that particular element! All good you may say, but! The light from distance stars, galaxies or nebulae will have to pass through the filter regardless, meaning light will be absorbed, the result? Objects will appear dimmer although the contrast will be higher. The best method to see distant objects either with binoculars or a telescope or the naked eye is to get away from all streetlights and other sources of artificial light. There are some fantastic locations to do this, dark sky discovery sites or Dark Sky Parks. Visiting these locations, you’ll not only be amazed at the number of stars that will appear as your eyes acclimatise to the low levels of light, but it will also give you the opportunity to form a bond with our past, our ancestors as little as 50 years ago but also as far back as we have been able to look up! Comets, galaxies, the Milky Way have all been immortalised in some form, Hailey’s Comet appearing in the Bayer Tapestry, something many of use many not see in the future (2062/2063) due to its reflected light being drowned out from photons emitted from artificial sources.
To find out more about dark sky sites in the UK or what events are taking place in the National Dark Sky Festival visit www.gostargazing.co.ukfor a comprehensive list of nearby events.
Or you can join astronomers from Yorkshire Astronomy and Go Stargazing at Tann Hill Pub, the highest and (probably) the best pub in the UK, situated in the Yorkshire Moors, a dark sky discovery site in February. Look out for our article in Sky at Night in February!