Newgrange

rcunning03

can somebody help resolve a discussion i'm having with my old man.

we were in newgrange last sunday (week before solistice) and when they turn off the lights you could see what i thought was sunlight on the floor of the passageway to the chamber, but my dad said it was just artifical light they used to try to show the effect of the solstice, but i reckon that it makes sense that sunlight would reach some part of the passageway (not the chamber) and that over the year it slowly goes further up the passageway till it hits the chamber on the solstice

My dad says the ONLY time any sun gets into the passageway is on the solstice

Was is sunlight or artifical light i saw on the floor

Also when is sunrise this sunday

cheers

Talliesin

Originally posted by rcunning03
can somebody help resolve a discussion i'm having with my old man.

we were in newgrange last sunday (week before solistice) and when they turn off the lights you could see what i thought was sunlight on the floor of the passageway to the chamber, but my dad said it was just artifical light they used to try to show the effect of the solstice, but i reckon that it makes sense that sunlight would reach some part of the passageway (not the chamber) and that over the year it slowly goes further up the passageway till it hits the chamber on the solstice

You will get some sunlight going someway along the passageway close to the solstice. Indeed you can get a pretty good effect when it is very close to the day (note that they generally make a big to-do up at Newgrange on the 21st of December even on those years, like this year, when the solstice is on the 22nd - the sun will be at the southern-most point relative to the stars from our viewpoint that it gets to this year at 2003-12-22T07:04Z).

This doesn't mean that you were right though, just that you could be. You could try phoning the people involved in handling the tourists at Newgrange perhaps.

Also when is sunrise this sunday

This depends on where you are in the country. in Dublin the sun will rise on 08:38 on Sunday and 08:39 on Monday .

It's worth noting that the solstice sunrise is not generally the latest sunrise in the year according to our clocks - our clocks work with days of exactly 24 hours (bar the occassional leap-second that only astronomers and a few other scientists need care about) whereas the earth's rotation is not that regular - "Noon" meaning the time the sun is exactly South isn't necessarily "noon" meaning 12:00 of a given day, even if you are standing in Greenwich Observatory. The latest sunrise will be around the end of the year, the earliest sunset was around the middle of the month, this tends to surprise people the first time they decide to meet the solstice sunrise and look up the times (however the day with the shortest time between sunrise and sunset does happen on the solstice).

rcunning03

ill ring them and find out either way i wish they could of let the lights off earlier

Gearoid

Another interesting thing i learnt the other day that with the universe constantly expanding Newgrange is now slightly "off" co ordination as it was built so long ago. It's like the pyramids which were aligned to stars I think...

Capt'n Midnight

http://www.crystalinks.com/precession.html
Every 72 years we actually move backward 1 degree. After 2100 years we move out of one age and into another.

Note: Precession is not constant - the wobble wobbles
http://www.museum.state.il.us/exhibits/ice_ages/precession_graph.html

google for Milankovitch