One of the most awe-inspiring events that can occur on our little planet is a solar eclipse. Long ago, the ancients considered solar eclipses as bad omens or even signs from the gods.
Even the word “eclipse” is derived from the Greek language and translates to “abandonment” or “downfall.” Even to this day, much mystery surrounds solar eclipses regardless of our current scientific knowledge.
These events even harbor gravitational paradoxes when they occur, and today we are going to present to you many known and unknown facts regarding solar eclipses, and answer questions such as:
- What is a solar eclipse?
- How many types of solar eclipses are there?
- Why are total solar eclipses so rare?
- Are solar eclipses dangerous?
- Do solar eclipses occur on other planets?
- Are there any paradoxes occurring during a solar eclipse?
What is a solar eclipse?
The Moon can be a mysterious mistress. In its utter beauty and magnificence, it can mesmerize us both frightfully and delightfully. But what exactly does the Moon do during a solar eclipse?
A solar eclipse is an event in which our Earth, or at least a portion of it, is engulfed in a shadow cast by the Moon during the daytime. This shadow can fully or partially block the sun’s light[1].
Solar eclipses occur around 2 to 5 times each year; it all depends on the geometry of the Sun, Moon, and Earth. However, the rarest solar eclipse, which is named “total solar eclipse,” – occurs once every 1-2 years.
Though solar eclipses can be beautiful, different parts of the world experience these events at different times. After all, the moon’s shadow isn’t so big [2].
The curious thing is that we may experience a solar eclipse on the same spot on Earth once every 375 years or so.
The Moon’s shadow during an eclipse is derived in three parts:
- Umbra
- Penumbra
- Antumbra
How many types of solar eclipses are there?
There are four types of solar eclipses[3]. They occur in different locations, and they vary in occurrence and duration:
- Total Eclipse
- Annular Eclipse
- Partial Eclipse
- Hybrid Eclipse
Total eclipses are the rarest types and the most beautiful. They cannot be seen from the North and South Poles. They happen when the Moon completely obscures the Sun, and only the faint solar corona is visible. This is also known as totality. The maximum width in the path of totality is around 269 km / 167 mi. It sweeps across an area of Earth’s surface of about 16,093 km / 10,000 mi.
The Moon moves across the Sun with a speed of around 2,250 km / 1,398 mi per hour. This type of eclipse lasts at a maximum of 7 minutes and 30 seconds.
The annular eclipse usually occurs when the Moon is farther away in its orbit than usual, and because of this, it is too “small” to cover the sun’s disk. This produces a bright ring of sunlight that shines around the Moon. It can last from 5 to 12 minutes.
A hybrid eclipse is a shifting event between a total and an annular eclipse. In some points on Earth, it appears as a total eclipse while in other areas, as an annular eclipse.
The partial eclipse is the most common type of eclipse. This event happens regularly as the Moon partially obscures the Sun. If the three celestial bodies won’t form a straight line in space, a partial eclipse is produced [4].
There are five factors which influence a solar eclipses' duration:
- The eclipse’s midpoint is near the subsolar point – “closest” to the Sun.
- The Earth’s rotation vector is aligned with the eclipse’s vector.
- The eclipses’ midpoint being very close to Earth’s equator.
- The current position of the Earth. The aphelion, which is the furthest position of a celestial body from the Sun.
- The Moon is almost exactly at perigee – its angular diameter being as large as possible.
Why are total solar eclipses so rare?
Hybrid eclipses are rare, but total eclipses are the rarest. They occur once every 18 months or so on average. Total eclipses also have reoccurrences in the same places on Earth, once every 360 to 410 years, and this is why they may seem even rarer to observers.
In each century there are, on average, around 240 total eclipses. These types of eclipses are rare because of the Moon’s orbit and closeness to Earth. If the Moon was closer, would have a perfectly circular orbit, and it was in the same orbital plane as us, a total eclipse would occur once every new moon.
Are solar eclipses dangerous?
Sadly, though solar eclipses are beautiful to behold, they are dangerous for our eyes [5]. For instance, looking at a total solar eclipse without protection will undoubtedly lead to eye injuries.
This happens because our eyes adjust to the sudden darkness, and our pupils dilate. They are striving to absorb light as much as they can, and we can suffer a shock if the Sun catches us by surprise.
We can suffer permanent eye damage from this. An annular eclipse is also dangerous, as well as hybrid eclipses. The partial eclipses aren’t so terrible, but protection is advised nonetheless.
Do solar eclipses occur on other planets?
When it comes to Pluto, both it and its giant moon Charon experience eclipses only on one of their sides.
Are there any paradoxes occurring during a solar eclipse?
Usually, during total eclipses, air temperatures drop, and gravitational paradoxes can sometimes occur. The physicist, Maurice Allais, reportedly witnessed unexplained movements. This phenomenon is named the Allais effect.
It is quite a controversial topic. In late 1970, both Saxl and Allen, two famous physicists, studied and observed a sudden change in the motion of a torsion pendulum during the solar eclipse. This phenomenon is called the Saxl effect.
Apart from these, on March 20, 2015, a solar eclipse had a significant impact on the power system. The production decreased, temperatures and wind power also suffered from this.
During solar eclipses, animals also seem to be affected. Reportedly, they seem to change their behavior, usually returning quickly to their hideouts while crickets have been observed to chirp.
Famous ancient eclipses
Solar eclipses have been recorded since at least 736 BC. The earliest claim, which is still disputed to this day, is that of the archeologist Bruce Masse. He linked an eclipse that occurred on May 10, 2087 BC, with a possible meteor impact in the Indian Ocean [7].
Long ago, during a battle between the Medes and the Lydians, a solar eclipse occurred. It is said that both sides laid down their weapons and made peace because of it. This account was written by the Greek historian Herodotus who also wrote that Thales of Miletus predicted the eclipse.
When it comes to the ancient Asians, the Chinese have recorded eclipses since at least 720 BC. It is said that the Chinese King Zhong Kang was an admirer of solar eclipses, to the point where he beheaded two astronomers for failing to predict an eclipse around 4.000 years ago.
However, the first “modern” observation with the use of a telescope, occurred in 1706 in France. Later, in 1715, the famous English astronomer Edmund Halley correctly predicted and even observed a solar eclipse that happened on the 3rd of May. Even later, the first photograph of an eclipse was taken. This happened on July 28, 1851.
Did you know?
– Many millions of years ago, there were no annular eclipses since the Moon was much closer to the Earth, and thus much “larger.”
– The Moon’s orbit around Earth becomes around 3.8 cm/1.5 inches more distant each year due to tidal acceleration.
– We won’t experience total eclipses forever. Millions of years in the future, our beloved Moon will be too far away to occlude the Sun completely.
– When our Earth experiences an eclipse, we continue to receive at least 92% of the amount of sunlight.
– Many websites can tell you when and where the next solar eclipses will occur. For instance, the next total eclipse in North America will occur on the 8th of April, 2024.
