Astronomy Lesson

Shaun Hately drednort at alphalink.com.au
Thu Jul 10 06:19:07 UTC 2003


No: HPFGUIDX 68982

Over the past week or so, I have made a couple of posts relating to 
the astronomical information contained in Order of the Phoenix - 
specifically looking at whether or not, the objects described as 
being observed during the astronomy exam could have been observed 
from Hogwarts location on the dates concerned. 

I should stress immediately that this is being done mostly as an 
intellectual exercise, for the interest of any fans who find this 
type of minutiae interesting. It is *not* intended as any type of 
criticism of JK Rowling. It would be absurd to expect an author to 
concentrate on making issues like this fit in a work of fiction.

But what I am considering is if the observations described could have 
been made based on the historical fact of what the night sky over 
Hogwarts looked like in the real world.

Since then, a few questions have been raised about those 
observations, primarily relating to where I had located Hogwarts. 
Some people have suggested that I should have been dealing with a 
location further north from that I was using, and so I have been 
looking into this.

Obviously Hogwarts cannot yet be precisely located. However, fan 
consensus seems to be summed up by the following contained in the 
HPfGU FAQs (http://www.hpfgu.org.uk/faq/geography.html)

"A number of facts from the books point to Scotland, a bit north of 
Edinburgh, and possibly closer to Aberdeen."

One list member, Steve/bboy_mn has given the likely location of 
Hogwarts some considerable though, and has come up with the following 
locations (and has stated he believes 1a, 1b, or 3 are the most 
likely locations) shown in the maps at:

http://www.homestead.com/BlueMoonMarket/Files/Hogwarts/hogwarts1.htm

As he made obviously put a significant amount of thought into these 
locations considering issues such as "terrain; mountains, lakes, 
rivers, absents of towns, railways, and remote location" and as they 
are broadly in line with what seems to be the fan consensus, I've 
decided to redo my posts using these locations.

These are, of course, assumptions - but they seem reasonable to me 
and are certainly more likely to be correct than my original 
assumption of an arbitrary location roughly in the middle of Scotland.

He has kindly provided me with the latitude and longitude of these 
locations as well as rough information on their elevation - 
elevations makes some difference to astronomical observations.

I've also had to make an assumption as to the height of the astronomy 
tower. We have very little information on this. However, we know that 
it is the tallest tower in the school, and we know that Hogwarts is a 
very large building. Assuming one dormitory floor for each year in 
Gryffindor, we know the Gryffindor tower would rise at least seven 
floors above the eight floors of the main school - and the astronomy 
tower is taller than Gryffindor tower.

So the astronomy tower must be at least fifteen floors tall. The 
thing is - the floors of a medieval castle like Hogwarts are in all 
probability of greater height than those of a modern building.

So - how tall to make the Astronomy Tower? The tallest medieval 
structures in Britain appear to have been the spires of Cathedrals 
which reached just over 400 feet at most.

I've decided to assume the height of the Astronomy Tower to be 500 
feet. This would make it taller than any Muggle building in the UK 
during the middle ages, and would allow a floor height of somewhere 
over 25 feet - not unreasonable for a castle type structure.

So - to the structure of this post.

We know takes place in June, on a Wednesday. If the year is 1996 
(which is the general fan consensus), we have 4 Wednesdays in June 
1996 - the 4th, the 11th, the 18th, and the 25th. Logically the exam 
should be either the 18th or the 25th, IMHO, but I will consider all 
4 dates.

We have four indications of astronomical information about the night 
in
question from Order of the Phoenix.

(I) The grounds are bathed in moonlight at 11pm.
(II) Sometime after midnight, Harry is able to find Venus in the sky
(III) Sometime after midnight, Harry is able to find the Moon in the
sky.
(IV) Harry completes a chart of Orion sometime after midnight, 
implying
it is visible - though it doesn't actually say it is.

I have three locations to work with, from Steve/bboy_mn maps.

(A)	57d30m39s N, 4d48m06s W - elevation 2050 feet.
(B)	57d47m13s N, 4d46m00s W - elevation 1500 feet.
(C)	57d01m60s N, 3d45m13s W - elevation 2500 feet.

For the purposes of my calculations, observations relating to point 
(I) will be considered at ground level, observations relating to 
points (II) (III) and (IV) will be considered at the assumed tower 
height (ground level + 500 feet).

For June 4th 1996, at location (A) 57d30m39s N, 4d48m06s W - ground 
elevation 2050 feet 

(I)	Not possible - the moon is certainly bright (87% full) but at 
11pm, has not risen yet. It will not rise until 11.26pm
(II)	Not possible - this would only be possible if the exam lasts 
for over four hours and Harry observed it during daylight and 
indications are it is much shorter than that. Venus will not rise 
until 4.11am, well after sunrise at this location (3.47am) 
(III)	Possible - the moon is up from 11.26pm to 8.21am
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 4.58am, considerably after sunrise.

For June 11th 1996, at location (A) 57d30m39s N, 4d48m06s W - ground 
elevation 2050 feet

(I)	Not possible - the moon is not very bright at all (16% full), 
so any light it shed would be negligible but at 11pm, it has not 
risen yet. It will not rise until 2.18am.
(II)	Not possible - this would only be possible if the exam lasts 
for nearly four hours and Harry observed it during daylight and 
indications are it is much shorter than that. Venus will not rise 
again until 3.45am, shortly after sunrise at this latitude (3.42am) 
(III)	Marginal, if the exam lasts until after 2.18am, this is just 
possible
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 4.31am, considerably after sunrise.

For June 18th 1996, at location (A) 57d30m39s N, 4d48m06s W - ground 
elevation 2050 feet

(I)	Not possible - the moon is close to new  (8% full), so any 
light it shed would be negligible but at 11pm, it has not risen yet. 
It will not rise until 7.31am.
(II)	Very marginal - this would only be possible if the exam lasts 
until after 3am Venus will not rise again until 3.19am, a little 
before sunrise (3.41am)
(III)	Not possible, the moon will not rise until hours after dawn.
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 4.03am, after sunrise.

For June 25th 1996, at location (A) 57d30m39s N, 4d48m06s W - ground 
elevation 2050 feet

(I)	Possible - the moon is reasonably bright (67% full), and is 
up until 1.01am.
(II)	Marginal - this would only be possible if the exam lasts 
until nearly 3am Venus will not rise again until 2.54am, before 
sunrise (3.43am)
(III)	Possible, the moon is in the sky until 1.01am.
(IV)	Extremely marginal - Orion will start to rise at 3.36 am 
(seven minutes before dawn) but only 2 of its faintest stars are up 
before the sun.

For June 4th 1996, at location (B) 57d47m13s N, 4d46m00s W - ground 
elevation 1500 feet.
(I)	Not possible - the moon is certainly bright (87% full) but at 
11pm, has not risen yet. It will not rise until 12.06pm
(II)	Not possible - this would only be possible if the exam lasts 
for over four hours and Harry observed it during daylight and 
indications are it is much shorter than that. Venus will not rise 
until 4.47am, well after sunrise at this location (4.22am) 
(III)	Possible - the moon is up from 12.06am to 9.00am
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 5.35am, considerably after sunrise.

For June 11th 1996, at location (B) 57d47m13s N, 4d46m00s W - ground 
elevation 1500 feet.

(I)	Not possible - the moon is not very bright at all (16% full), 
so any light it shed would be negligible but at 11pm, it has not 
risen yet. It will not rise until 2.55am.
(II)	Not possible - this would only be possible if the exam lasts 
for nearly four hours and Harry observed it during daylight and 
indications are it is much shorter than that. Venus will not rise 
again until 4.21am, shortly after sunrise at this location (4.17am) 
(III)	Marginal, if the exam lasts until after 2.55am, this is just 
possible
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 5.07am, considerably after sunrise.

For June 18th 1996, at location (B) 57d47m13s N, 4d46m00s W - ground 
elevation 1500 feet.

(I)	Very marginal - the moon is close to new  (8% full), so any 
light it shed would be negligible but at 11pm, it hasn't quite set 
yet. It won't set until 11.14pm.
(II)	Very marginal - this would only be possible if the exam lasts 
until after 3am Venus will not rise again until 3.55am, a little 
before sunrise (4.16am)
(III)	Not possible, the moon will not rise until 8am.
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 4.40am, after sunrise.

For June 25th 1996, at location (B) 57d47m13s N, 4d46m00s W - ground 
elevation 1500 feet.

(I)	Possible - the moon is reasonably bright (67% full), and is 
up until 1.40am.
(II)	Marginal - this would only be possible if the exam lasts 
until around 3.30am Venus will not rise again until 3.30am, before 
sunrise (4.18am)
(III)	Possible, the moon is in the sky until 1.40am.
(IV)	Extremely marginal - Orion will start to rise at 4.12 am (six 
minutes before dawn) but only 2 of its faintest stars are up before 
the sun.

For June 4th 1996, at location (C) 57d01m60s N, 3d45m13s W - ground 
elevation 2500 feet.

(I)	Not possible - the moon is certainly bright (87% full) but at 
11pm, has not risen yet. It will not rise until 11.59pm
(II)	Not possible - this would only be possible if the exam lasts 
for over four hours and Harry observed it during daylight and 
indications are it is much shorter than that. Venus will not rise 
until 4.50am, well after sunrise at this location (4.25am) 
(I)	Possible - the moon is up from 11.59pm to 8.59am
(II)	Not possible - Orion is below the horizon and will not even 
begin to rise until 5.34am, considerably after sunrise.

For June 11th 1996, at location (C) 57d01m60s N, 3d45m13s W - ground 
elevation 2500 feet.

(I)	Not possible - the moon is not very bright at all (16% full), 
so any light it shed would be negligible but at 11pm, it has not 
risen yet. It will not rise until 2.54am.
(II)	Not possible - this would only be possible if the exam lasts 
for nearly four hours and Harry observed it during daylight and 
indications are it is much shorter than that. Venus will not rise 
again until 4.24am, shortly after sunrise at this location (4.20am) 
(III)	Marginal, if the exam lasts until after 2.54am, this is just 
possible
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 5.07am, considerably after sunrise.

For June 18th 1996, at location (C) 57d01m60s N, 3d45m13s W - ground 
elevation 2500 feet.

(I)	Very marginal - the moon is close to new  (8% full), so any 
light it shed would be negligible but at 11pm, it hasn't quite set 
yet. It won't set until 11.07pm.
(II)	Very marginal - this would only be possible if the exam lasts 
until after 3am Venus will not rise again until 3.57am, a little 
before sunrise (4.19am)
(III)	Not possible, the moon will not rise until 8.09am.
(IV)	Not possible - Orion is below the horizon and will not even 
begin to rise until 4.40am, after sunrise.

For June 25th 1996, at location (C) 57d01m60s N, 3d45m13s W - ground 
elevation 2500 feet.

(I)	Possible - the moon is reasonably bright (67% full), and is 
up until 1.37am.
(II)	Marginal - this would only be possible if the exam lasts 
until around 3.30am Venus will not rise again until 3.31am, before 
sunrise (4.22am)
(III)	Possible, the moon is in the sky until 1.37am.
(IV)	Extremely marginal - Orion will start to rise at 4.12 am 
(five minutes before dawn) but only 2 of its faintest stars are up 
before the sun.

Yours Without Wax, Dreadnought
Shaun Hately |webpage:
http://www.alphalink.com.au/~drednort/thelab.html
(ISTJ)       |email: drednort at alphalink.com.au | ICQ: 6898200 
"You know the very powerful and the very stupid have one thing in
common. They don't alter their views to fit the facts. They alter the 
facts to fit the views. Which can be uncomfortable if you happen to 
be one of the facts that need altering." The Doctor - Doctor Who: The 
Face of Evil Where am I: Frankston, Victoria, Australia





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