Solar eclipse; how is it a natural phenomenon? It is rare that natural or astronomical phenomena can surpass a solar eclipse in terms of the intensity of their drama and effect on humans. By understanding its inner processes and hidden mechanisms, you can broaden your horizons; take a step into the world of astrology. There can be two such periods in one calendar year, i.e., at least 2 eclipses in 365 days. Furthermore, in each season, there may be several such phenomena, but no more than 5 per year, in different parts of the world.
Method and time of the eclipse
Descriptions of how solar eclipses occur have generally remained unchanged throughout the recorded history of observations. At the Sun’s edge, a dark spot appears on the lunar disk, creeping from the right, gradually increasing in size, becoming darker and more transparent.
The larger the Moon covers the surface of the light, the darker the sky becomes, and bright stars appear on it. Shadows lose their normal contours and become blurred.
The air gets colder. Depending on the geographic latitude of the eclipse strip, its temperature can drop by up to 5 degrees Celsius. Animals become nervous at this time and often rush around searching for shelter. The birds are silent; some go to sleep.
The Moon’s dark disk creeps closer to the Sun, leaving an ever thinner crescent from it. Eventually, the Sun disappears completely. Around the enclosed black ring, the Sun’s crown can be seen – a silvery glow with blurred edges. Some illumination is given by the dawn flashing across the horizon around the viewer, an unusual lemon-orange color.
The moment of complete disappearance of the solar disk lasts no more than three to four minutes. The maximum possible time of a solar eclipse, calculated by a unique formula based on the ratio of the angular cross sections of the Sun and the Moon, is 481 seconds (just under 8 minutes).
Then the black lunar disk moves further to the left, revealing the Sun’s rays. At this moment, the Sun’s corona and glowing ring disappear, the sky lights up, and the stars go out. The gradually released Sun emits more and more light and heat, and nature returns to its standard form. It is important to note that in the Northern Hemisphere, the Moon moves along the Sun’s disk from right to left, while in the Southern Hemisphere, it moves from left to right.
The main types of solar eclipse
The area of the globe seen above during a total solar eclipse is always limited by a narrow and long strip formed in the path of a conical lunar shadow, which crosses the surface of the Earth at a speed of more than 1 kilometer per second. The width of the strip usually does not exceed 260-270 kilometers; in length, it can reach 10-15 thousand kilometers.
The paths of the Earth’s movement around the Sun and the Moon around the Earth are ellipses, so the distances between these celestial bodies are not fixed values and can fluctuate within certain limits. Thanks to this principle of natural science, a solar eclipse is different.
At a much greater distance from the total eclipse strip, you can observe a partial solar eclipse, which in everyday language is often also called partial. In this case, for the observer at a place outside the strip, the paths of the night and daylights intersect so that the solar disk is only partially closed. Such phenomena occur much more often and in a much larger area than the area of a solar eclipse can be several million square kilometers.
A partial eclipse occurs annually in nearly every location on Earth. Still, it goes unnoticed by most people outside the astronomical community. A person who rarely looks at the sky will see such a phenomenon only when the Moon covers half of the Sun, i.e., if the value of its phase approaches 0.5.
Calculating the phase of a solar eclipse in astronomy can be done with formulas of varying complexity. In the simplest version, it is determined by the ratio of the diameter of the part blocked by the Moon to the total diameter of the Sun’s disk. Phase value is always expressed as a decimal fraction.
Sometimes the Moon moves a little further than usual from the Earth, and its angular size (apparent) is smaller than the apparent size of the Sun’s disk. In this case, an annular or annular eclipse: the Sun’s sparkling ring around the Moon’s black ring. At the same time, it is impossible to observe the solar corona, stars, and dawn since the sky almost does not darken.
The width of the observation strip with a similar length is much more significant – up to 350 kilometers. The penumbra width is also greater – up to 7340 kilometers in diameter. If the phase is equal to one or even more during a total eclipse, then the annular phase value will always be greater than 0.95 but less than 1.
It is worth noting that a fascinating fact is that many types of eclipses that occur fall in the era of human civilization. Since the Earth and the Moon formed as celestial bodies, the distance between them has been slowly but steadily increasing. With the changing spaces, the entire eclipse schedule is the same, similar to the one described above.
More than a billion years ago, the distance between our planet and its satellite was less than it is now. Accordingly, the apparent size of the lunar disk was much larger than that of the Sun. There were only total eclipses with a much wider shadow band; the observation of coronas was almost impossible, as was the formation of annular eclipses.
In the distant future, the distance between the Earth and the Moon will be even more remarkable after millions of years. The distant descendants of modern humanity will be able to observe only annular eclipses.
Science experiments for hobbyists
Observing solar eclipses helped make several significant discoveries. For example, even in the time of the ancient Greeks, the sages of that time concluded the possible movement of heavenly bodies and their spherical shape.
Over time, research methods and instruments made it possible to conclude the chemical composition of our star about the physical processes in it. The well-known chemical element helium was also found during the eclipse observed in India by the French scientist Jansen in 1868.
A solar eclipse is one of the few astronomical phenomena that amateurs can observe. And not only for observations: anyone can make a possible contribution to science and record the conditions of rare natural phenomena.
What an amateur astronomer can do:
- Mark the moments of contact of the solar and lunar discs;
- Fix the duration of what is happening;
- Draw or photograph a solar corona;
- Participate in an experiment to refine the data on the diameter of the Sun;
- In some cases or when instruments are used, prominent words can be seen;
- Take photos of the circular glow on the horizon;
- Make simple observations of changes in the environment.
Like any scientific experience, observing eclipses requires following several rules to help make the process one of life’s most memorable events and protect the viewer from real health damage. First, from possible thermal damage to the retina, the probability of which increases to almost 100% with the unprotected use of optical devices.
Therefore, the principle of solar observation: be sure to use eye protection. Such can serve as special light filters for binoculars and telescopes and chameleon masks for welding. In the most challenging cases, ordinary smoked glass is suitable.
It is relatively safe to observe only for a short period, just a few minutes, during the total eclipse. Be especially careful during the initial and final phases when the brightness of the solar disk is near maximum. Taking a break from observation is recommended.