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Author Topic: Where would I have to be standing to have 24 hours continuous daylight or night?  (Read 5337 times)

Anastasia.fr.1

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In my exam i got asked this question: Where would i be standing if i got 24 hours of daylight? then the next question said: Where would you be stanging if you got 24 hours of night time? I did not know the answer, do you? ??? ???
« Last Edit: 09/03/2008 10:51:27 by chris »


 

another_someone

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In both cases, on midsummers day, on the north or south pole (midsummer on the south pole is December/January, midsummer on the north pole in June/July) you will have 24 hours of daylight.  The same location, on midwinters day, you will have 24 hours of darkness.

I have not actually been on the north or south pole itself, but I have been within the Arctic circle, in Northern Scandinavia, just a few days after midsummers day (anywhere within the Arctic/Antarctic circle will have the same effect on midsummers day, but as you get further from the actual midsummers day itself, the effect becomes ever more restricted to the poles themselves); and have driven into a camp site at 1 o'clock in the morning in broad daylight (the sun was just on the horizon itself, like it was sunset or sunrise - it was interesting to see the change in colour of the light from sunset to sunrise, without it getting dark in between), while other campers were just packing up their tent to drive off.
 

Offline Professor Gaarder

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you don't even need to be on a polar end of the earth. I took a trip to sweden/norway a couple of years ago and there was daylight for three days straight. it was eerie.
 

another_someone

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you don't even need to be on a polar end of the earth. I took a trip to sweden/norway a couple of years ago and there was daylight for three days straight. it was eerie.

I did qualify the above by saying that actually anywhere within the Arctic/Antarctic circle will do - in fact, that is what defines the Arctic/Antarctic circle, it is the region where for at least one day in the year there is no night.  As you move deeper inside the polar circles, the period of time for which there is no night (and, in winter, the time for which there is no day) increases, until you get to the pole itself, where you have 6 months of continuous daytime, and 6 months of continuous nightime.
 

Offline Professor Gaarder

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makes sense . . . experiencing it firsthand, cool as it is, doesn't really give you the proper information like the studies do.
 

Offline lightarrow

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Apart from Anastasia's examination, another way to interpret the question is of being in a place where we have 24 h of daylight and then 24 h of night time, for example in a planet which day lasts 48 hours, or on Earth in an airplane travelling towards west at about 830 km/h. However it's not totally clear to me, non native english speaking, if "where would I be standing" includes that second possibility.
« Last Edit: 02/03/2008 22:21:37 by lightarrow »
 

another_someone

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in an airplane travelling towards west at about 830 km/h. However it's not totally clear to me, non native english speaking, if "where would I be standing" includes that second possibility.

I suppose if you are into 24hr wing walking, it might be a possibility ;)

Th airspeed you would need would depend on the latitude you were flying, but are you sure that 830Km/h would be enough.  I would have thought closer to 1000mph (this assumes equatorial latitude).
« Last Edit: 02/03/2008 23:52:11 by another_someone »
 

Offline lightarrow

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in an airplane travelling towards west at about 830 km/h. However it's not totally clear to me, non native english speaking, if "where would I be standing" includes that second possibility.

I suppose if you are into 24hr wing walking, it might be a possibility ;)

Th airspeed you would need would depend on the latitude you were flying, but are you sure that 830Km/h would be enough.  I would have thought closer to 1000mph (this assumes equatorial latitude).

I used 6350 Km as Earth's radius and an equatorial orbit. Assuming an altitude of 10,000 m the computation gives me 832 km/h.
 

another_someone

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I used 6350 Km as Earth's radius and an equatorial orbit. Assuming an altitude of 10,000 m the computation gives me 832 km/h.

6350Km + 10Km = 6360Km.
6360 x 2 x π = 39961Km.
39961Km/24hr = 1665Km/hr.

OK, I assume what you did was assume you only wanted to fly half way around the world in 24 hours, in order to double the length of the day - so you are probably correct in that.  That means you can stay subsonic (but not by a wide margin), and it is doable with a commercial airliner (although you would have problems with carrying enough fuel - but ripping out the passenger seats to add more fuel tanks might suffice).
 

Offline Pumblechook

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I was going to say it says nowt about being on Earth or near to it.

 

Offline lightarrow

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I used 6350 Km as Earth's radius and an equatorial orbit. Assuming an altitude of 10,000 m the computation gives me 832 km/h.

6350Km + 10Km = 6360Km.
6360 x 2 x π = 39961Km.
39961Km/24hr = 1665Km/hr.

OK, I assume what you did was assume you only wanted to fly half way around the world in 24 hours, in order to double the length of the day - so you are probably correct in that. 
Thanks!
 

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