Eclipse is a phenomenonastronomical darkened total or partial of a star due to the passage of some celestial body in front of a source of light. There are two categories of eclipse: the eclipse solar and the eclipse lunar.
Eclipse Types
There are two categories of eclipses: eclipses solar and the eclipses lunars.
Types of solar eclipses
Total Solar Eclipses: the Moon completely covers the sunlight, casting its shadow on the Earth;
Partial solar eclipses: the Moon is not perfectly aligned with the Sun, covering only part of its luminosity;
Annular solar eclipses: the Moon's apparent size is not enough to fully cover sunlight. This phenomenon results in the appearance of a ring around the Moon's shadow.
Types of Lunar Eclipses
There are the lunar eclipses penumbrals,partial and totals. All of these eclipse types are related to positionrelative of the observer on Earth.
penumbral eclipses: the moon's surface is slightly darkened when crossing the region of the twilight cone produced by the Earth;
Partial Lunar Eclipses: only part of the Earth's shadow is cast on the Moon;
Total Eclipses: the entire lunar surface is covered by the Earth's shadow.
solar eclipse
O eclipsesolar occurs when the Moon stands in front of the Sun so that its shadow is projected onto the Earth's surface. During the occurrence of this type of eclipse, a small region of the Earth becomes dark because of the projectiongivesshadowgivesMoon. It is in this region, called umbra, that you observe the eclipsesolartotal.
On the outskirts of the umbra, is the dimness, where it is possible to observe a eclipsesolarpartial. The difference between umbra and dimness is the luminosity of the region. The places where you can observe the total eclipse are darker than the surrounding regions.
Lookalso: Shadow and penumbra formation
Note the figure below, which shows a diagram of how the eclipsesolar. It is also possible to observe the regions of umbra and dimness, where we can view the eclipsetotal and partial, respectively:
Solar eclipses are gradual, that is, the Moon takes some time to cover the Sun, so it is common to see pictures of the stages of an eclipse, like the following image:
By observing the moon phases, it is possible to imagine that every New Moon a solar eclipse occurs, however, this does not happen because the plane of the lunar orbit is lightlyrotated (about 5.2º) in relation to the Earth's orbit around the Sun (called the ecliptic). Therefore, solar eclipses only occur at positions where the lunar orbit passes through the ecliptic plane. Look at the figure below:
In the figure above (not to scale), we can see the planes of the lunar and ecliptic orbits. When the two intersect, solar eclipses can occur.
Lookalso: Why doesn't the Moon fall to Earth?
lunar eclipse
O eclipselunar occurs when the Earth shadow, produced by the Sun, is projected on the moon, covering it. Similar to a solar eclipse, a lunar eclipse can only occur when the moon's orbit coincides with the ecliptic. Without the small difference of 5.2° between these two orbits, lunar eclipses would occur whenever there was a Full Moon.
Take a look at the figure below, which shows a diagram showing the formation of a lunar eclipse:
The following figure shows a sequence of photos taken during a lunar eclipse:
By Rafael Hellerbrock
Master in Physics
