These days, predicting eclipses is easily done using computers. Prediction is made by determining the position of the Sun and the Moon at a time, and calculating if an eclipse happens. The same procedure is then repeated numerous time, each for a different time.
The victims of the flat-Earth dogma insist nobody can predict eclipses from the position of the Sun and the Moon. They believe NASA simply used the Saros cycle to predict eclipses by calculating the interval between eclipses. They are wrong.
Continue reading “Predicting Eclipses Does Not Require the Saros Cycle or NASA’s Involvement”
Light waves are not always moving in a straight line. When it passes through a medium of a different refractive index, the waves will deviate. The phenomenon is called refraction and described according to Snell’s Law.
Earth’s atmosphere has variation in air density that depends on the altitude. As the refractive index changes with the density of the medium, light waves passing through Earth’s atmosphere also experience refraction.
Continue reading “Atmospheric Refraction”
During a total solar eclipse, the Moon is right between the Earth and the Sun. Thus, the near side of the Moon does not receive any sunlight. But while it is dark, it still gets some light reflected by the surface of the Earth. This phenomenon is called Earthshine.
Some flat-Earthers argue that a solar eclipse is not caused by the blocking of the Sun by the Moon, but by another, mysterious celestial body. The reason is that eclipses are incompatible with their beliefs about the motion of the Sun and the Moon.
Earthshine proves that they are wrong.
Continue reading “Earthshine Proves the Moon Obscures the Sun During a Total Solar Eclipse”
A page on NASA’s website is at the center of the attention of flat-Earth followers. It is a page created by Fred ‘Mr. Eclipse’ Espenak, explaining the Saros cycle. Here’s the first paragraph from the page:
The periodicity and recurrence of eclipses is governed by the Saros cycle, a period of approximately 6,585.3 days (18 years 11 days 8 hours). It was known to the Chaldeans as a period when lunar eclipses seem to repeat themselves, but the cycle is applicable to solar eclipses as well.
After they discovered that the said ‘Chaldeans’ was a civilization from 25 centuries ago, they got excited and jumped to the conclusion that NASA used ancient technology to predict eclipses, and thus eclipses can’t be predicted from the motion of the Sun, Earth and Moon themselves.
Like other similar cases, this tells us more about the flat-Earthers themselves than about NASA.
Continue reading “The Saros Cycle and Saros Series”
“The Sun and the Moon have been observed to appear in the sky at the same time during a total lunar eclipse. This cannot happen if the Earth is round because the Sun, Earth and Moon are supposed to be in a straight line during a total lunar eclipse. So, the globe Earth model is wrong!”
Some flat-Earthers observed the Sun and Moon appear at the same time during a total lunar eclipse. Predictably enough, they pick the most far-fetched explanation, and conclude the Earth is not round. But in reality, this phenomenon is well documented and clearly explained.
Continue reading “Selenelion: The Phenomenon Where The Sun and Moon Are Visible During a Total Lunar Eclipse”
“Looking at the pictures of the progression of a lunar eclipse, the Moon turns red, but there’s no apparent change of brightness of the Moon as it progresses from full moon to total eclipse. Therefore, a total lunar eclipse cannot be the result of the Earth casting its shadow on the surface of the Moon.”
Some flat-Earthers —presumably never seen a total lunar eclipse in person before— actually claim that.
Continue reading “Brightness of a Total Lunar Eclipse”
The Moon turns red during a total lunar eclipse. But if the Moon is completely in Earth’s shadow, then how does it turn red?
The atmosphere of the Earth acts like a giant lens and refracts some of the sunlight into the surface of the Moon.
Continue reading “Blood Moon: Why The Moon Turns Red During a Total Lunar Eclipse”
Apparently it is a very common misconception that the phases of the Moon is caused by the Earth’s shadow. Not only among flat-Earthers, but the general public as well. The difference is that flat-Earthers will usually jump to conclusion, and have some outlandish interpretation about this.
In reality, the phases of the Moon happen because we see a different sunlit part of the Moon at different time. Not because it is over the shadow of the Earth.
Continue reading “Lunar Phase and Lunar Eclipse”
Practically every depiction of the Sun, Earth and Moon is drawn not to scale. Flat-Earthers sometimes use this fact to point out the alleged “failure of modern science” to describe motion of celestial bodies, or something like that.
But in fact, the reason is simply that it is practically impossible to create a model of the solar system with real scale, using static images, that is still effectively describes the objects it is trying to explain.
Continue reading “Not to Scale: Depictions of the Solar System”