Astronomy group - Padraig Sands  Aligning the telescopes - Julie Ormonde   Binoculars at night  planisphere

Astronomy equipment can be cheap or expensive. Generally you get what you pay for, as there are so many things to consider before you start parting with hard-earned cash. For instance: Go-To telescopes are amazing and really look the biz but what will you do if the battery runs out? Where will you point that super doper eyepiece if you don’t know that sky without a machine to tell you where to aim? Common sense says that you should learn the sky before you buy and ‘the best telescope to buy is the one that you will use often’.   Too many beautiful telescopes end up lying in the shed wrapped inside the very box it came in simply because it was too big and cumbersome.




eyes collage

Our eyes are truly amazing. Looking at the photo above it is hard to believe that it is the little black dot on the center of the eyeball providing us with all the visual information in the visible world around us. That dot is only a 2-4 millimeters in diameter and we call it the pupil. The older one gets the smaller the pupil is, perhaps that’s way young children have such captivating eyes. The pupil  is really a hole located in the center of the iris of the eye allowing light to enter the retina. It appears black because light rays entering the pupil is absorbed by the tissues inside the eye. The pupil gets wider in the dark but narrower in light. It can take up to 45 minutes for human eyes to get accustomed to the darkness allowing us to see more of what is around us.  Yet, in just an instant – the striking of a match, mobile phone light, car headlights, outside light suddenly switched on – and your eyes are back to where they were before the light intrusion. To make matters worse – you will have to wait yet another 45 minutes to get your eyes dark adapted so be careful. If you go Stargazing remember the longer you are outside in the dark the more stars you will see but it takes only an instant for your eyes to lose that dark adaptation. Above information copied from an easy to follow beginners guide to astronomy called The Universe…. go check it out.


Binoculars at nightThe easy mobility and simpler operation of binocular’s make them an easy choice for anyone considering astronomy. They are compact, simple devices and the ultimate in portable, easy-to-use equipment. The best binoculars for astronomy use are (7 x 50) or larger, though any size binocular can be used for viewing Stars and other sky objects,  choosing quality equipment promises better results. Don’t forget the weight of the binoculars though, its all very well getting super-dooper big ones, only to find that your hands shake and ache after only a short time. There is also a great difference in price between a telescope and binoculars. Transporting a telescope and setting it up has always been a difficult assignment because the instrument is cumbersome and setup can be an involved patience stretching process.  There are many beautiful sights to be seen through binoculars such as: the star fields of the Milky Way – Star Clusters such as the Pleiades and Hyades – and ghostly comets, which can only be truly appreciated in low-power, wide-field binoculars.


Local south kerry astronomy groupEvery amateur astronomer wants to own a telescope ­ and the bigger the better. But one has to be practical and consider storage as well as setting-it-up problems. Unless one is lucky enough to be able to have the telescope in a permanent position with a removable roof, and living in an area that is light pollution free, then my advice would be to restrain yourself and only buy what you would be comfortable with.
There are two main types of telescope: refractors (the spyglass type) which use lenses to collect and focus light; and reflectors, which collect light with a mirror. To choose the right telescope, you need to know the relative advantages of each type.
Telescopes are judged not their magnification but their aperture, i.e. the diameter of the main lens or mirror. Don’t mind all that nonsense on the box, and don’t be pulled in by all those wonderful Hubble type pictures displayed on the box either. When astronomers refer to a ‘small’ telescope they mean one with a small aperture. The aperture governs how much light the telescope collects ­ and the more light it collects, the more you can see. Hence it is best to get the largest aperture telescope you can afford, whether a refractor or reflector.


Eyepieces random selectionToday there are so many different varieties of eye-pieces with so many different claims to function that the subject of telescope eye-pieces would cover a whole web-site all of its own. Simply put an eyepiece consists of several “lens elements” in a housing, with a “barrel” on one end. The barrel is shaped to fit in a special opening of the instrument (telescope) to which it is attached. The image can be focused by moving the eyepiece nearer and further from the objective – for example the Moon. Telescopes have a focusing mechanism (a little wheel) to allow movement of the shaft in which the eyepiece is mounted, without needing to manipulate the eyepiece directly. The focal length of an eyepiece is the distance from the principal plane of the eyepiece where parallel rays of light converge to a single point. When in use, the focal length of an eyepiece, combined with the focal length of the telescope to which it is attached, determines the magnification. It is usually expressed in millimeters when referring to the eyepiece alone. When interchanging a set of eyepieces on a single instrument, however, some users prefer to refer to identify each eyepiece by the magnification produced. To properly learn about eye-pieces it is better to attend an astronomy class on the subject, or watch the video above.



A planisphere is a great astronomy tool that consists of a circular star chart attached at its center to an opaque circular overlay that has a clear elliptical window or hole so that only a portion of the sky map will be visible in the window or hole area at any given time. The chart and overlay are mounted so that they are free to rotate about a common pivot point at their centers. The star chart contains the brightest stars, constellations and (possibly) deep-sky objects visible from a particular latitude on Earth. The night sky that one sees from the Earth depends on whether the observer is in the northern or southern hemispheres and the latitude. A planisphere window is designed for a particular latitude and will be accurate enough for a certain band either side of that. Planisphere makers will usually offer them in a number of versions for different latitudes. Planispheres only show the stars visible from the observer’s latitude; stars below the horizon are not included.



Simply put – there are so many extra’s that one can purchase for the pursuit of  astronomy that trying to cover it in a paragraph is not enough. It all depends on how much you are willing to spend and how deeply involved you want to get on the whole subject. The best suggestion is to Google the internet and find a good astronomy store which will give you all the information you need.


Stargazing in the kerry dark sky reserve Michael Sheehan


To fully maximize the experience of viewing our Dark-Sky you should consider hiring a Stargazing Guide (private visits can be arranged at your holiday home for parties and Bar-B-Que’s).  Or maybe you might consider hiring a Heritage Guide … it’s YOUR holiday – go make the most of it.


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