A stupid question? You tell me!

civildefence

OK I am posting this in astronomy because although it has nothing to do with space, it would be directed at those who have experience with telescopes. It is a bit of a ridiculous question, but still a job for mythbusters or the barstool scientist. Here goes..

You are on top of a high point on the east coast of Ireland, lets say Bray Head in Co. Wicklow. It is a clear day with perfect conditions and there are no obstructions in your way. You have a powerful telescope set up and it is precisely directed at a known landmark on the west coast of Wales, say Holyhead Ferry Port.

Would you be able to see Holyhead clearly if at all or would factors like curvature of the Earth, mist etc. make this impossible?

Bear in mind i'm an idiot on the subject so if you wanna reply with things like "don't be so stupid!", you're stating the obvious anyway!

By the way does anybody with a good telescope want to bust this myth? Are you just that crazy?

rockmongrel

No, the curvature of the earth would be too great, and of course there are the weather conditions.

The Gnome

The distance from Bray to Holyhead is about 60 miles. Standing at Bray Head you can see for roughly 38 miles before the curvature of the Earths kicks in. (Not including the effects of atmospheric refraction or poor weather.)

So the answer is no!

civildefence

The Gnome wrote: »

The distance from Bray to Holyhead is about 60 miles. Standing at Bray Head you can see for roughly 38 miles before the curvature of the Earths kicks in. (Not including the effects of atmospheric refraction or poor weather.)

So the answer is no!

Oh well, feeling tearful now
Maybe the same question with the Isle of Man?

The Gnome

Nope, doesn't look there's anywhere high/close enough. Could be possilbe via Fata Morgana but probably not...

cottz2006

There's no such thing as a stupid question if you don't know the answer:pac:

civildefence

cottz2006 wrote: »

There's no such thing as a stupid question if you don't know the answer:pac:

True, true

NickFromTipp

From where I work in Leopardstown it is possible to see the Mourne mountains in Co. Down on a very clear day. I think that's not far off 60 miles. However, I'm probably only seeing the peaks, and, our canteen is on the 6th floor with an unobstructed view. Pretty cool though.

NickFromTipp

Forgot to say... Atmospheric refraction can make it possible to see about 5degrees below the geometric horizon. Need very clear conditions though.

civildefence

NickFromTipp wrote: »

From where I work in Leopardstown it is possible to see the Mourne mountains in Co. Down on a very clear day. I think that's not far off 60 miles. However, I'm probably only seeing the peaks, and, our canteen is on the 6th floor with an unobstructed view. Pretty cool though.

OK this man's scenario, clear as can be, expensive telescope on the roof of the office block in Leopardstown, looking at the kind gentleman who has volunteered to climb to a peak in the Mourne Mountains just for our experiment, can we see our lad waving his flag in the distance?

Calibos

I have heard anecdotally that on a super clear day its possible to see the peaks of Welsh mountains from Bray head. Course it has to be clear, here, there and everywhere in between obviously. Never seen them myself even with 15x70 bino's. Have seen what I believed to be the Mournes up the east coast though.

Unless you can give me a loan of a helicopter, I won't ever be able to tell you what a 16inch Dob could see from the top of Bray head

Kevster

Not sure about bray Head, but you can certainly see the Welsh mountains on a clear day from Howth Head. It's kinda cool just sitting down there watching the ships approaching from afar too. If you look at a world map, the Irish Sea is barely noticeable.

Frank Ryan Jr

If (and let me stress if)
you had a flat earth, very steady or little atmosphere and disturbance of air
then I'd say ya, you could.

I took a photo of the International Space Station with the shuttle docked to it a few years ago as it passed over head through a small scope with camera
(web) attached.



As far as I can remember the ISS was around 300 KM away at the time of passing so it just go's to show you how much of an effect
air / heat and cold / curve of the earth all have on what you are suggesting.

Flukey

From some of the higher points in Wicklow you can certainly see Wales. A plane is a bit different, but you don't have to be too high flying out of somewhere like Liverpool or Manchester to see Ireland's east coast.

spacetweek

Have never heard anything about miles but the formula I use is
\/13h
where h is your height above ground in meters. Some examples:

Eye Level 1.75m 4.7 km - So on a beach the horizon is 5 k's away.
Bray Head 250m 57 km exactly
Sugarloaf 500m 80 km exactly
Lugnaquilla 900m 108 km - I'm not sure if other mountains would be in the way for this one.


However I climbed the Sugarloaf on a clear sunny day a few years ago and Wales (well, its mountains) was clearly visible from there.

tricky D

rockmongrel wrote: »

No, the curvature of the earth would be too great, and of course there are the weather conditions.

The Gnome wrote: »

The distance from Bray to Holyhead is about 60 miles. Standing at Bray Head you can see for roughly 38 miles before the curvature of the Earths kicks in. (Not including the effects of atmospheric refraction or poor weather.)

So the answer is no!

The Gnome wrote: »

Nope, doesn't look there's anywhere high/close enough. Could be possilbe via Fata Morgana but probably not...

Easily seen on a clear day.
http://www.boards.ie/vbulletin/showthread.php?t=2055597309

The Gnome

tricky D wrote: »

Easily seen on a clear day.
http://www.boards.ie/vbulletin/showthread.php?t=2055597309

Mountains yes, Holyhead no.