Arctic Circle: 66° 56'
Where are you pulling this from?
From wiki, the Arctic circle is 66° 34'.
Based upon axial tilt (also from wiki), it works out to be 66° 34'.
That means the difference is 43', or 0.72°, not the >1° you claim.
I confused these two conventions : 66° 33´ 39" (or 66.56083°)
That's an easy enough mistake to make, but it was immediately obvious to those familiar with the location of the tropics and polar circles.
However, you still can't escape your fate regarding this issue, since 43' difference is still a huge reason for sunset in Haparanda :
1. Locations further north than the Arctic Circle and further south than the Antarctic Circle experience no full sunset or sunrise on at least one day of the year, when the polar day or the polar night persists continuously for 24 hours, but full polar night occurs only at a latitude of more than about 72.5 degrees.
2. If the center of the sun (sun's apparent angular diameter at aphelion = 31') is aligned with the Arctic Circle at Summer Solstice, it means that even at the Arctic Circle the sun is partially bellow the horizon at the very peak of Summer Solstice. Thence : see No 1, again.
That doesn't matter. The definition of sunset for astronomical purposes is when
all of the sun's disk is below the horizon, not just any part of it, or the center.
What has become very clear is that you are unfamiliar with the definition of astronomical sunset.
3. Since Haparanda is located at 65° 50' 30" N it means that the Sun Disk when looking from Haparanda is 30' bellow the horizon because when we lower that portion of the Sun which is above the horizon at the Arctic Circle (we subtract 15' from 43') how much of that difference (43') remains? The answer is 28' (which is only 3' less than the entire apparent angular diameter of Sun Disk), isn't that so?
Yes, but you're neglecting the approximately 30' of refraction under normal conditions. The effect of this refraction is to make objects appear higher in the sky than they actually are. With 30' of refraction and your 28' the upper limb of the sun is geometrically below the horizon, a little bit of the the upper limb is visible above the horizon, which means the sun has not set. (See the reply to your point
2.)
4. Maybe Mr Paul B. Du Chaillu didn't measure by himself when the Sun exactly had set (and rose) in Haparanda 150 years ago, it is much more likely (almost certainly) that he took these information from some old astronomical manual (almanac) and cited it in his book.
Which is exactly why this is not reliable data. We do not know where those numbers came from or what they represent. Maybe it was overcast the night of the 21st and he couldn't tell if the sun set at all so he simply reported some information he found somewhere. Perhaps that data was for the time the center of the solar disk was predicted to be below the horizon, which some tables intended for navigational purposes may have provided.
We cannot tell.However, such an explorer would have noticed that the Sun had stayed at the horizon for a full 24 hours had such spectacle really happened 150 years ago.
It wouldn't have stayed at the horizon for a full 24 hours. At its highest it would have been more than 46° above the horizon. We don't know if he witnessed the position of the sun around local midnight or not or if he had a clear view all the way to the true horizon.
At least someone would have told him that such phenomena could occur in Haparanda had any (ancient-still alive-at that time) citizen of Haparanda ever experienced such phenomena.
You're speculating. Maybe he didn't speak Swedish or the local dialect whatever language was used there at the time, and they didn't speak French. He may not have considered the opinions of the locals to be useful and didn't bother to ask. Who knows?
Yes, Alpha was right, It was a travelogue, so what???
It's anecdotal, that's what.
The times it reports are of unknown provenance. Since it wasn't a scientific or technical report, establishing their veracity and specifying their meaning was considered unnecessary. What he said may have been close enough to correct for its intended purpose, which was to be read for amusement by people who would in all likelihood never go there.
5. So, we can accept that because along the Arctic Circle one half of Sun's Disk is always above the horizon at Summer Solstice the sun never (phenomenally) sets bellow the horizon. But even though if it is not full-sunset, it is still sunset (we can call it : a half-sunset), see No 1, again.
Redefining "sunset" so that it loses its meaning may be the only hope you have to salvage your argument. See my reply to No
2. for the definition of astronomical sunset that is used now.
Rovaniemi - City in Finland (66.5039° N, 25.7294° E - located exactly at the Arctic Circle), is the capital of Lapland, in northern Finland. Almost totally destroyed during World War II, today it’s a modern city known for being the "official" home town of Santa Claus, and for viewing the Northern Lights.
In June and July there are 30 consecutive days when the sun is above the horizon (from June 7th till July 6th) in Rovaniemi.
Sun's declination on June 7th = N22° 42'
Sun's declination on June 21th = N23° 26'
The difference = 44'
Now we have here the same problem as in Haparanda case, because phenomenally you can say that the sun didn't set because it's twilight, but you can't claim that the sun didn't set (in astronomical terms). And we talk here in astronomical terms, not in phenomenological terms.
It's indeed a problem - again, for you.
Let's see... geometrically the center of the sun is 44' below the horizon. 15' of solar radius puts the upper limb 29' below the horizon. 30' of nominal refraction raises the upper limb to 1'
above the horizon so, astronomically, the sun has not set.
6.
Sun's declination on July 14th = N21° 46' (1° 40' lower than on June 21th)
Bodo Norway Latitude = 67° 16' 49.2852'' N (43' north of Arctic Circle)
1° 40' - 43' = 57' (almost one full degree)
This means that the center of the sun (in the following video) when the sun is closest to the horizon should have to be 57' (astronomically) above the horizon, and 1,5° (when we add refraction index) above the horizon (phenomenally)...This means that in the following video the apparent position of the center of the sun (when the sun is closest to the horizon line - somewhere at 40 sec in the video) has to be 1,5° higher above the real (astronomical) position of the Sun (above the Arctic Circle) at June 21th (the peak of Summer Solstice)...It means that we have to add more than three apparent Sun's Disk above Sun's real (astronomical) position of the Sun (above the Arctic Circle) at June 21th, so to get the final phenomenological result which doesn't correspond with what we can see in the following footage (because the sun is (apparently) even partially bellow the horizon line in some sequences of this video) :
That is very confusing. Let's see if we can parse out what you're trying to say. Please correct any errors in interpretation.
"Sun's declination on July 14th = N21° 46' (1° 40' lower than on June 21th)
Bodo Norway Latitude = 67° 16' 49.2852'' N (43' north of Arctic Circle)"
The center of the sun is 1° 40' south of the tropic of Cancer, and the view is from 43' north of the arctic circle. This is about what I calculated going the other way at a similar time after the December solstice previously, and I'll accept the location given as correct, so, OK.
"This means that the center of the sun when the sun is closest to the horizon should have to be 57' (astronomically) above the horizon, and 1,5° (when we add refraction index) above the horizon (phenomenally)..."
The meaning of this is not clear. Do you mean that when the center of the sun
appears to be on the horizon, you think it must really be 57' above the horizon geometrically (neglecting refraction) and another 33' higher to account for refraction? That is incorrect. Why do you think so?
If refraction is around its nominal value, when the center of the sun
appears to be on the horizon, it's really about 30' below the horizon geometrically.
"This means that in the following video the apparent position of the center of the sun (when the sun is closest to the horizon line - somewhere at 40 sec in the video) has to be 1,5° higher above the real (astronomical) position of the Sun (above the Arctic Circle) at June 21th (the peak of Summer Solstice)...It means that we have to add more than three apparent Sun's Disk above Sun's real (astronomical) position of the Sun (above the Arctic Circle) at June 21th, so to get the final phenomenological result which doesn't correspond with what we can see in the following footage (because the sun is (apparently) even partially bellow the horizon line in some sequences of this video)"
Your previous statement is in error, so this conclusion based on it is wrong.
At the solstice, if you're 43' north of the arctic circle, the center of the sun at its lowest point would be 43' above the horizon geometrically. Using
Rab's table and interpolating, an object at 0° 43' above the horizon geometrically would appear to be at inclination angle around 1° 07' due to a deflection of about 0° 24' due to refraction in standard atmospheric conditions.
This video proves that your refraction excuse is totally bogus or that refraction even works in an opposite direction (which raises this problem to a new level)!
It proves nothing of the sort. In fact, it 'proves' nothing at all but does support the existence (and variability) atmospheric refraction.
So, what about the phenomenon the video shows? If the sun at its lowest point on July 14 is 1° 40' lower than its lowest point on the solstice, then, geometrically, its center should be 0° 57' below the horizon. With a 15' nominal radius, the upper limb of the sun is 0° 42' below the horizon. Using 31' for nominal refraction (Rab's table at 0° apparent inclination) leaves 0° 11' unaccounted for.
The video was obviously recorded above water level, but how far above the water is not known. If it's 10 m, then the visible horizon will be about 6' below the ideal horizon, making up more than half of that 11'. 20 m would lower the visible horizon by about 9', almost all that's needed to bring the uppermost part of the sun back into view. Since the sun does, in fact, drop completely below the apparent horizon, that might fully explain why it visible for as much of the time as it is.
Also note that the table is based on "standard" atmospheric conditions, but these can obviously vary (see the several threads in these forums for examples where the higher skyscrapers in the Chicago skyline are visible from distances far in excess of where they would be visible under normal conditions). Given how the sun appears to skitter along the horizon for several minutes, it looks like ducting is is in play. Look it up. The necessary conditions are not uncommon immediately above bodies of water.
In short, there is
no disagreement between that video and our well-established and well-tested understanding of solar system geometry and a rotating spherical earth with a stratified atmosphere.
Since we know the length of the sidereal day is not constant, but varies very slightly short term with a long-term lengthening
trend, the lengths of the seasons measured in Hipparchus' time is consistent with the precession of the equinoxes, and you can present no reliable evidence for your postulated "wandering sun", it looks like you're zero out of three for the arguments you've presented in this thread alone.
I see you just posted more Inuit stuff.
"The sun is out longer" appears looks like a rehash of what we went over earlier. Where's the data, not stories?
"During the longer days, the rising of the sun appears to be coming from the north." Well, duh... not only does it
appear to be rising from the north, it
is rising from the north on those very long days. That's exactly what is expected to happen at high northern latitudes, and what it has done for all of human history and much, much, longer. Think about it... the sun will be lowest when it's due north; those days where there is a brief time when the sun drops below the horizon, it will be in the north, setting just west of due north and rising again just east of due north.
Did he really just notice this? So much for "the wisdom of Inuit elders."