There are many observable facts that advocates of the flat earth model do not accept. Daylight is one of them.
There are two major facts about daylight that any model of the shape of the earth must explain. These are its longitudinal and latitudinal variations.
Anyone who has ever spoken to another person who lives in another time zone is familiar with the longitudinal variation of daylight. At any given point in time one half of the earth is in darkness and one half is in light, and that variation falls along longitudinal lines.
I live in the Pacific time zone; my brother lives in the Eastern time zone. So we are always 3 hours different in time. If I call him at 7 PM my time it’s 10 PM his time. I’m in late evening and he’s in night.
If it is noon in the Pacific time zone at a time of year when no time zone is observing Daylight Savings the time will be:
- 1 PM in Denver Colorado
- 2 PM in Chicago
- 3 PM in New York City
- 8 PM in London
- 9 PM in Berlin
- 11 PM in Moscow Russia
- 4 AM in Beijing
- 5 AM in Tokyo
- 10 AM in Anchorage Alaska
This is not just a human imposed artifice. When it is 11 PM in Moscow it really will be dark outside. When it is 3 PM in New York City it really will be mid-afternoon and therefore daylight outside.
The flat earth model cannot account for this fact. Once the sun appears above the horizon of a flat earth all regions of the planet will experience daylight equally. None will be in darkness.
The spherical earth model accounts for longitudinal variation in daylight quite simply and naturally. From a single point source of light– i.e. the sun– only one half of a sphere can be illuminated at any one time. We have a huge number of confirmations of this phenomenon in the form of photographs that have been taken from artificial satellites and manned space vehicles. For example, this photo was taken by the crew of the Apollo 15 mission:
The photo shows Africa and Europe in shadow while South America is in daylight. Here’s another that was taken on the Apollo 13 mission that shows a portion of North America in daylight:
And here’s one that shows the earth as a crescent:
None of these photographs would be possible if the earth were shaped like a disc.
These variations in daylight are longitudinal in that they fall along the lines of the earth’s meridians– that is, lines of longitude. Latitudinal variations are those that have to do with the distance a location on the earth’s surface is from the equator. Regions that are closer to the North and South poles experience far more hours of daylight during their summer months than do equatorial regions, and far fewer hours of daylight during their winter months. I live close to the 47th parallel. At the summer solstice we receive about 16 hours of sunlight in the day, and at the winter solstice we receive about 8.5 hours. A person living on the equator would receive 12 hours of sunlight every day of the year. Here is a short video that shows what it is like to live north of the Arctic Circle in the summer:
Furthermore the northern regions experience summer when the southern regions are in winter. In winter the sun never rises above the horizon on at least one day per year for any location north of the Arctic Circle.
The flat earth model cannot explain this phenomenon. When it is daylight in any one region of the flat earth it would be daylight for all. But that is not true on planet Earth.
The spherical earth model explains this phenomenon quite simply and elegantly. The earth is inclined at an angle of about 23 degrees relative to its plane of rotation about the sun. That inclination means that regions close to the north pole are tilted toward the sun by 23 degrees during the summer months and are tilted away from it by 23 degrees during the winter months. When tilted toward the sun the polar regions will see the sun above the horizon for more hours; when tilted away the sun will appear above the horizon for fewer hours.
This variation in daylight is directly related to latitude, as it is dependent on the distance a region is from the equator. It is the basis of the seasons, something that most people do believe in– maybe even most flat earth propagandists.