The Greek inter linear directly translates ''no may be appearing'' for ''the day shone not''. It wouldn't suggest a shortening of the literal day/night, as it seems to refer to the actual appearance of the sun/moon/stars.
It says for the night likewise. The day shone not for the third part of it, and the night likewise. The third part of a day is 4 hours, and the third part of the night is 4 hours. Therefore, the day shone not for four hours and the night shone not (not appearing) for four hours. This actually supports exactly what I am saying - in the tribulation (at some point) we have a 16 hour day.
The only thing that could make this possible is God's super natural intervention, and even at that shortening the day by a few hours would require speeding up Earth's rotation by a considerable amount. This would result in mostly everything on the face of the Earth shooting off its surface at a tangential trajectory into space. Unless He'd chose to do it gradually. I still hold to this not being what the passage implied, though. It is going to be a plague of darkness, that much is clear.
I'm quite certain that God can find a way to shorten the day by 8 hours with everything surviving if he wishes. I was simply speculating on a possible cause. The book of Revelation is clear that the plagues are caused by God and are therefore of supernatural origin.
In addition, in my opinion it seems that the human race actually
knows that God is causing these plagues. These verses would seem to indicate this:
"
8And the fourth angel poured out his vial upon the sun; and power was given unto him to scorch men with fire.
9And men were scorched with great heat, and
blasphemed the name of God, which hath power over these plagues: and they repented not to give him glory.
10And the fifth angel poured out his vial upon the seat of the beast; and his kingdom was full of darkness; and they gnawed their tongues for pain,
11And
blasphemed the God of heaven because of their pains and their sores, and repented not of their deeds." Rev. 16:8-11
''Mutilate'' means a removal, if someone were to lose an arm they would simply be using one less arm...in the same manner the sun being mutliated by one third of ''its'' parts means it will simply give 1/3 less light. Very clear and very obvious.
Verse 22 -> the word is ''lopped'' and better translates to ''discounted''.
"22And except
those days should be shortened, there should no flesh be saved: but for the elect's sake
those days shall be shortened." Mt. 24:22
Shortened, #2856, koloboo, to mutilate, in NT: to shorten, abridge, curtail.
Example: the days of Noah --> anytime this kind of phrase is used, it is not pertaining to the literal everyday (in this example, Noah's days), it's a reference to that particular period of time as a whole. Jesus clearly meant to say that tribulation is going to occur but is going to be metered, in that this period in Earth's history is going to be shortened lest nothing survives.
Problem with this is the tribulation is for a very real, set time and is not at all "shortened" by any stretch of the imagination. The times have already been set forth and prophesied and thus cannot be altered:
"
5And there was given unto him a mouth speaking great things and blasphemies; and
power was given unto him to continue forty and two months." Rev. 13:5
The AC's reign is for 42 months. That is a set time period and cannot possibly be shortened or altered without altering prophecy itself, which by definition cannot be altered. The end of the GT is the return of Christ, who destroys the AC in Armageddon at the end of 42 months.
The key with the shortening of the days is the phrase "the day shone not for the third part of it, and the night likewise." As you pointed out, this actually means that the day "did not appear" for the third part of it, and the night "likewise."
So neither the day nor the night will appear for the third part of it, which indicates a literal shortening of the 24-hour day.
Let's look at the verse a little more deeply:
"
12And the fourth angel sounded, and the
third part of the sun was smitten, and the third part of the moon, and the third part of the stars; so as the third part of them was darkened, and the day shone not for a thirdpart of it, and the night likewise." Rev. 8:12
Shone, #5316, phaino,
1) to bring forth into the light, cause to shine, shed light
2) shine
a) to shine, be bright or resplendent
b) to become evident, to be brought forth into the light, come to view, appear
1) of growing vegetation, to come to light
2) to appear, be seen
3) exposed to view
c) to meet the eyes, strike the sight, become clear or manifest
1) to be seen, appear
d) to appear to the mind, seem to one's judgment or opinion
Now, if we had a 16 hour day, an acceptable description of this would be that 1/3 of the sun, moon, and stars were smitten and darkened. The word for darkened is #4654, skotizo, and means:
1) to cover with darkness, to darken
2) to be covered with darkness, be darkened
a) of heavenly bodies as deprived of light
b) metaph.
1) of the eyes
2) of the understanding
3) of the mind
In other words, 1/3 of the sun, moon, and stars being smitten = the sun, moon, and stars not shining for 1/3 of their time. This follows with a description of just that - the day shone not (appeared not) for the third part of it, and the night likewise. This would then reference back to Christ's discouse in Mt. 24:22, where he speaks of the days of the tribulation being shortened. We have a problem, since there cannot be a shortening of the tribulation since it is for a set time (42 months, namely), but there is no problem if Christ is referring to the
literal days being shortened.