Pushing back the Horizon

So lately I’ve been thinking about a ‘fact’ I was told as a child: on a clear day you can see as far as Wales from the top of Mt. Lienster.

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Being young and fascinated I was always a little awestruck at the notion I could see all the way across the sea and into another country, but it was never clear enough when I was up there.

So fast forward to last Friday when I went to Inis Mór with the family. We were on the boat trying to spot the coast through the overcast and misty day. My younger brother was reading the leaflets handed out by the tourist information guys and informed me that Dún Aengus is a fort built on the side of a 100 meter high cliff face. My number senses began tingling. How far could you see from there? Could you see the mainland, the other islands, boats how far out at see?

I had 40 mins to kill and so the 3G went on and I began googling. Wikipedia politely informed me you can use the Pythagoras theorem to estimate, based on assumption of a spherical earth and no atmospheric refraction or occlusion. Distance to the Horizon in km = 3.57 by square root of the vision height.

I whipped out the mobile office excel app and banged in the numbers for 1 to 100 meters and bobs your mother’s brother. 35 km.

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Distance from Dún Aengus to mainland is 12 km, so on a clear day you’d be likely to see exactly what your enemy clan on the mainland were plotting.

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View from Dún Aengus on a clear day looking northeast towards the mainland of galway, Ireland. Clearly visible are the coast and other landmasses in the ocean.

So back to Co Wexford and normality today and sitting out having a beer and a barbecue I remembered my question. Could you actually see to Wales?

Using the same formula as before and data from wikipedia we get a best case distance of 128.93 km.

Daft Logic says the closest point of land in the mainland UK from Mount lienster is indeed Wales, a little island called Ramsay island near the town of St. David’s off the coast of Pembrokeshire Coast national park a distance of 123.75 km.

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The closest point of land in Wales from Mount Lienster is off the coast of Pembrokeshire.

That’s just inside our calculated visible distance. Amazingly enough, it turns out to just be on the limit of plausibility.
Score one for science and maths I guess!

Edit: since posting this I did a little more digging around and found two very interesting images.

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This map shows signal strength from the transmitter atop Mount Lienster. We can see it is strongest in areas closest to the transmitter, with “shadows” cast behind the hills, and weakening as the distance becomes greater from the source. Notably, the signal reaches well into Wales.

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Mt. Snowden in Wales is at a distance of 189 km and an elevation of 1,085 m, making it an excellent point on the horizon to search for, right about 72.5 degrees East of North.

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Essential blogging

So I’m living in San Diego for just over a week now, and I think we could say I have any of the ‘must purchase immediately’ shopping done. I mean, I found a bike and a futon outside some dudes house who wanted to get rid of them, along with a busted up surf board that we now use as a table, but we had to BUY everything else.

So what do Irish students buy when they land in San Diego?

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If you manufacture anything you see on this blog, congratulations. You have an essential product for the Irish student market. Only about 20,000 of us here for the summer. You sir, are onto a winner.

I’m a Scorpio and…

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So I’m talking to a young upwardly mobile couple in the bar today, and discussing everything from tonights international ‘friendly’ with the England Soccer team, to apple vs android and everything in between, when she mentions that a milestone birthday is coming up, in November (yeah, that important!), and I mention my birthday is November also. So suddenly she’s telling me about how we’re both Scorpios, and that’s why we get along so well and how he’s a Leo, but just barely so he’s got traits from (?whatever comes before Leo) and how that has some profound effect on how they blah nblah blah.
It comes up how there are twelve horoscopes and twelve months, but they don’t exactly line up. So I pay no pass on it, and go about my day until I’m on the phone to the girlfriend and I see there is a star on horizon, and I see it flicker.
I remember seeing a light like that in the sky while looking up at Jupiter or Venus when I was young, and thinking maybe its one of the planets. Then I said on the phone to the girlfriend ‘there is a planet in the north west part of the sky’ and the penny dropped. The only star (visible to me) or planetary body to stay in one place is the north star. All the rest are constantly moving across the sky (when really its the rotation of the earth that’s moving the lights across my sky) and it suddenly occurred to me that not only am I moving relative to them, but they also move relative to the sun.

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So that’s what it means when they say ‘Saturn is in Gemini’, its a reference to where the body is relative to the ‘top’ side of the Sun, like a calendar to keep track of where things are.

But now my predicament lies in how we designated ‘north’! Or Capricorn, as I believe its designated, The first of the horoscopes in our calendar. Is it linked to where the sun is on our horizon at noon? The solstice? The equinox? (Or is that moons?)

What concerns me is how it was decided that the names be designated to these ever moving, ever ponderable, or how it was decided the lengths and durations of the solar seasons would run for. How to explain to so many a concept so foreign. If I could explain that kind of depth to another, why couldn’t I convince them that my design is best.
Understanding how to explain is where it all starts. If you can manage that, you can sell them whatever you want to sell them. And that’s what’s its all about, sales baby.