How long are your days?

Quote from: Professor Gaypenguin on September 22, 2008, 06:12:34 AM

I missed sunrise but according to the official source my day is 12h 15m today.

My day should be a bit longer than twelve hours too according to Ubuntu. Odd.

Not really.  You are forgetting about atmospheric refraction (about 1/2 degree).  When the sun or moon appears to be touching the horizon it is actually just below the horizon (which is how you can get a selenelion).  The actual 12:00 hour day/night will be in a few days.

I didn't catch sunrise this morning, but it did seem to start getting light out about the right time.

Not really.  You are forgetting about atmospheric refraction (about 1/2 degree).  When the sun or moon appears to be touching the horizon it is actually just below the horizon (which is how you can get a selenelion).  The actual 12:00 hour day/night will be in a few days.

You mean it was a few days ago.

I went to see the sunset but the conspiracy was one step ahead of me and hid it behind the clouds so I couldn't see anything. The bastards.

And the meteorological people said my day was more than 12hours and I trust the conspiracy more than you Markjo 

Quote from: markjo on September 22, 2008, 09:17:17 AM

Not really.  You are forgetting about atmospheric refraction (about 1/2 degree).  When the sun or moon appears to be touching the horizon it is actually just below the horizon (which is how you can get a selenelion).  The actual 12:00 hour day/night will be in a few days.

You mean it was a few days ago.

No, I mean it will be in a few days.  Remember that atmospheric refractions causes the sun to appear slightly higher above the horizon than it really is, thereby giving us a few extra minutes of daylight.  An equinox should not be confused with an equilux.

# Although the word "equinox" implies equal length of day and night, as is noted elsewhere, this is not true. For most locations on earth, there are two distinct identifiable days per year when the length of day and night are closest to being equal. Those days are commonly referred to as the "equiluxes" to distinguish them from the equinoxes. Equinoxes are points in time, but equiluxes are days. By convention, equiluxes are the days where sunrise and sunset are closest to being exactly 12 hours apart. This way, you can refer to a single date as being the equilux, when, in reality, it spans sunset on one day to sunset the next, or sunrise on one to sunrise the next.

# The equilux counts times when some direct sunlight could be visible, not all hours of usable daylight, which is anytime there is enough natural light to do outdoor activities without artficial light. This is due to twilight, and this part of twilight is officially defined as civil twilight. This amount of twilight can result in more than 12 hours of usable daylight up to a few weeks before the spring equinox, and up to a few weeks after the fall equinox.

Quote from: Osama  bin Laden on September 22, 2008, 09:19:50 AM

Quote from: markjo on September 22, 2008, 09:17:17 AM

Not really.  You are forgetting about atmospheric refraction (about 1/2 degree).  When the sun or moon appears to be touching the horizon it is actually just below the horizon (which is how you can get a selenelion).  The actual 12:00 hour day/night will be in a few days.

You mean it was a few days ago.

No, I mean it will be in a few days.  Remember that atmospheric refractions causes the sun to appear slightly higher above the horizon than it really is, thereby giving us a few extra minutes of daylight.  An equinox should not be confused with an equilux.

Quote from: http://en.wikipedia.org/wiki/Equinox#Myths.2C_fables_and_facts

# Although the word "equinox" implies equal length of day and night, as is noted elsewhere, this is not true. For most locations on earth, there are two distinct identifiable days per year when the length of day and night are closest to being equal. Those days are commonly referred to as the "equiluxes" to distinguish them from the equinoxes. Equinoxes are points in time, but equiluxes are days. By convention, equiluxes are the days where sunrise and sunset are closest to being exactly 12 hours apart. This way, you can refer to a single date as being the equilux, when, in reality, it spans sunset on one day to sunset the next, or sunrise on one to sunrise the next.

# The equilux counts times when some direct sunlight could be visible, not all hours of usable daylight, which is anytime there is enough natural light to do outdoor activities without artficial light. This is due to twilight, and this part of twilight is officially defined as civil twilight. This amount of twilight can result in more than 12 hours of usable daylight up to a few weeks before the spring equinox, and up to a few weeks after the fall equinox.

Yes, so it was a few days ago.

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Which is due to atmospheric refraction.

Quote from: markjo on September 22, 2008, 03:38:11 PM

Quote from: Osama  bin Laden on September 22, 2008, 09:19:50 AM

Quote from: markjo on September 22, 2008, 09:17:17 AM

Not really.  You are forgetting about atmospheric refraction (about 1/2 degree).  When the sun or moon appears to be touching the horizon it is actually just below the horizon (which is how you can get a selenelion).  The actual 12:00 hour day/night will be in a few days.

You mean it was a few days ago.

No, I mean it will be in a few days.  Remember that atmospheric refractions causes the sun to appear slightly higher above the horizon than it really is, thereby giving us a few extra minutes of daylight.  An equinox should not be confused with an equilux.

Quote from: http://en.wikipedia.org/wiki/Equinox#Myths.2C_fables_and_facts

# Although the word "equinox" implies equal length of day and night, as is noted elsewhere, this is not true. For most locations on earth, there are two distinct identifiable days per year when the length of day and night are closest to being equal. Those days are commonly referred to as the "equiluxes" to distinguish them from the equinoxes. Equinoxes are points in time, but equiluxes are days. By convention, equiluxes are the days where sunrise and sunset are closest to being exactly 12 hours apart. This way, you can refer to a single date as being the equilux, when, in reality, it spans sunset on one day to sunset the next, or sunrise on one to sunrise the next.

# The equilux counts times when some direct sunlight could be visible, not all hours of usable daylight, which is anytime there is enough natural light to do outdoor activities without artficial light. This is due to twilight, and this part of twilight is officially defined as civil twilight. This amount of twilight can result in more than 12 hours of usable daylight up to a few weeks before the spring equinox, and up to a few weeks after the fall equinox.

Yes, so it was a few days ago.

Well, if you live in the southern hemisphere of a round earth, then yes, I suppose that it was a few days ago.  For those of us living in the northern hemisphere of a round earth, then it should be on or about Friday (at least where I live).

Well, if you live in the southern hemisphere of a round earth, then yes, I suppose that it was a few days ago.  For those of us living in the northern hemisphere of a round earth, then it should be on or about Friday (at least where I live).

Obviously.

Quote from: Professor Gaypenguin on September 23, 2008, 12:56:34 AM

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Which is due to atmospheric refraction.

wouldn't it be due to the position of the sun?

Quote from: Osama  bin Laden on September 23, 2008, 01:01:23 AM

Quote from: Professor Gaypenguin on September 23, 2008, 12:56:34 AM

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Which is due to atmospheric refraction.

wouldn't it be due to the position of the sun?

If is wasn't for atmospheric refraction then the day of the equinox would also be the equilux (equal daylight and night).  But since the RE does have atmospheric refraction, the equilux is a few days off from the equinox.

Quote from: Professor Gaypenguin on September 23, 2008, 11:02:26 AM

Quote from: Osama  bin Laden on September 23, 2008, 01:01:23 AM

Quote from: Professor Gaypenguin on September 23, 2008, 12:56:34 AM

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Which is due to atmospheric refraction.

wouldn't it be due to the position of the sun?

If is wasn't for atmospheric refraction then the day of the equinox would also be the equilux (equal daylight and night).  But since the RE does have atmospheric refraction, the equilux is a few days off from the equinox.

Ok I'm confused, I'm still not with it. But I'll take your word for it

Quote from: markjo on September 23, 2008, 11:50:24 AM

Quote from: Professor Gaypenguin on September 23, 2008, 11:02:26 AM

Quote from: Osama  bin Laden on September 23, 2008, 01:01:23 AM

Quote from: Professor Gaypenguin on September 23, 2008, 12:56:34 AM

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Which is due to atmospheric refraction.

wouldn't it be due to the position of the sun?

If is wasn't for atmospheric refraction then the day of the equinox would also be the equilux (equal daylight and night).  But since the RE does have atmospheric refraction, the equilux is a few days off from the equinox.

Ok I'm confused, I'm still not with it. But I'll take your word for it

Just file it under RE equinox trivia and have a good day.

Quote from: Professor Gaypenguin on September 23, 2008, 11:58:59 AM

Quote from: markjo on September 23, 2008, 11:50:24 AM

Quote from: Professor Gaypenguin on September 23, 2008, 11:02:26 AM

Quote from: Osama  bin Laden on September 23, 2008, 01:01:23 AM

Quote from: Professor Gaypenguin on September 23, 2008, 12:56:34 AM

Yeah so its not atmospheric refraction, its just that the equinox isn't the day when the days are all the same.

Which is due to atmospheric refraction.

wouldn't it be due to the position of the sun?

If is wasn't for atmospheric refraction then the day of the equinox would also be the equilux (equal daylight and night).  But since the RE does have atmospheric refraction, the equilux is a few days off from the equinox.

Ok I'm confused, I'm still not with it. But I'll take your word for it

Just file it under RE equinox trivia and have a good day.

Okey doke 

I am not going to lie I never went outside to see the sunrise or sunset. If you look at local weather websites you can get a quick glance at the fact that countries around the world had about 12 hour days. You have to understand when you go outside and watch a sunrise or set it wont be an exact time.
When I prepare a form called a 175-1 for pilots to fly a lot of times they will ask for the twilight hours. This is the time before sunrise or right after sunset where there is still enough visible light to see, this occurs from the light reflecting off the atmosphere.
But the fact remains that days in the northern hemisphere will get shorter and in the southern they will get longer.

I want my days to get longer damnit! This place gets so depressing midwinter

I want my days to get longer damnit! This place gets so depressing midwinter

You mean when it gets dark and cold? That's the only time I'll voluntarily go outside for any other reason than going to work. The sun sucks.

I don't mind the cold when there's snow but when you only get a couple of hours of daylight a day it kinda sucks