The distance to the Sun was first determined with a good accuracy from worldwide observations of the transit of Venus. A transit of Venus is a phenomenon where Venus passes in front of the Sun. By measuring the time Venus spends crossing in front of the Sun from two or more locations on the surface of the Earth, it is possible to calculate the distance to the Sun.
Flat-Earthers insist that it is impossible to determine the distance to the Sun because nobody has ever gone to the Sun before. They are wrong. Using simple geometry, the distance to the Sun can be determined from the observations of the transit of Venus.
Continue reading “Determining the Distance to the Sun from the Transit of Venus”
The apparent size of the Sun is practically constant throughout the day. This can only happen if the Sun is practically at the same distance all day.
In the flat-Earth model, the Sun is close to the surface at the distance of about 5000 km (3500 miles). The Sun is supposed to be moving in a circle, and it completes the circling motion once in a day. This fact should cause the Sun’s apparent size to change during the day. But it does not happen. The Sun’s constant apparent size is evidence that the flat-Earth model is wrong, and that the Sun is very far away.
Continue reading “The Apparent Size of the Sun”
Any diagram showing two or more celestial bodies is almost never drawn in the correct scale. The reason is that in most cases, any two celestial bodies are spaced too far away relative to their sizes. It is just not possible to draw them in the correct scale and still effectively describes what we want to explain. We don’t have much choice other than drawing them not to scale.
The perpetrators of flat-Earth disseminate the allegations that the diagrams were drawn not to scale because of evil intentions, and not because of legitimate technical reasons. Some people don’t understand this and fell victim to flat-Earth indoctrination.
Continue reading “Total Solar Eclipse, Drawn to Scale”
If we look south in any location in the southern hemisphere, we are going to see the same set of stars. The stars are seen rotating around the south celestial pole, in the Octans constellation, nearby the star Sigma Octantis.
This phenomenon is unexplainable in the flat-Earth model. Looking at the so-called ‘flat-Earth map’, we should see the different set of stars on the different location in the southern hemisphere. The reason is that the so-called ‘flat-Earth map’ does not represent the real Earth.
Continue reading “Stars in the Southern Sky: Evidence That the Earth is a Rotating Sphere”
Jupiter possesses four large moons: Io, Europa, Ganymede, and Callisto. These are called the Galilean Moons. They are easy to observe and the first objects found to orbit a planet other than the Earth.
Flat-Earthers are often seen demanding proof that an object can orbit another object. All they have to do is to use a telescope to observe Jupiter and its Galilean moons.
Continue reading “Galilean Moons: The First Objects Observed to Orbit Another Object”
Sunlight can be broken into its constituent colors using a prism. The colors are the optical spectrum of the Sun. They are the same colors on rainbows. On careful observation, the spectrum is not perfectly continuous, but it has dark lines scattered over the entire spectrum. It turned out that from the lines, we can tell the composition of the Sun without physically getting there.
Some flat-Earthers think that it is impossible for us to determine the composition of the Sun, as it is impossible for anyone to visit the Sun without getting roasted in the process. They are wrong. The composition of the Sun can be determined from the spectral lines, or more specifically for the Sun: the Fraunhofer lines.
Continue reading “Fraunhofer Lines”
Diurnal motion is the apparent daily motion of stars around the two celestial poles due to Earth’s rotation. The stars move in a peculiar way that can only be explained in the spherical Earth model.
All the differences of diurnal motion that occur in the different latitudes on can never be explained in a flat Earth.
Continue reading “Diurnal Motion – Possibly the First Evidence of Spherical Earth”
Anyone who is in the northern hemisphere can observe the star Polaris, located very close to the north celestial pole. As a result, when observed casually, Polaris appears practically stationary in the same position.
Flat-Earthers claim that the fact Polaris appears stationary as ‘evidence’ that the Earth is stationary: if the Earth is in motion, then Polaris should appear in motion too. They are wrong. Polaris appears stationary because it is very far and its motion can’t be visually observed in the scale of a human life.
Continue reading “The Distance to Polaris”
Mercury and Venus are closer to the Sun compared to the Earth. The best condition to observe these planets is during some time after sunset or before sunrise. In some cases, they are even visible in the day.
Many flat-Earthers think that it should be impossible to observe Mercury & Venus as they are closer to the Sun. They are wrong.
Continue reading “Observing Mercury and Venus”
If Earth’s gravity pulls everything towards the Earth, then how can satellites stay up there and are not falling towards the Earth?
The answer is that satellites orbit the Earth. They have the correct velocity with respect to Earth’s position and gravitational pull.
Continue reading “How Satellites Can Orbit and Stay Up There”