Eclipse
Astronomical event that occurs when an astronomical object is temporarily obscured because of the shadow of another object.
Syzygy- when three object align in a line and middle object block the view of object on another side.
Types of Eclipse
There are mainly three types of eclipse depending upon relative location.
1. Total Eclipse- Associated with Umbra region.
Umbra(Latin word)- Shadow
2. Annular Eclipse- Associated with AntUmbra region.
AntUmbra(Latin word)- Ante(before) + Umbra(Shadow)
3. Partial Eclipse- Associated with PenUmbra region.
PenUmbra(Latin word)- Pen(nearly) + Umbra(Shadow)
To understand these regions let's have a look on Sun(as 1st astronomical object) and moon(as the middle object)
Solar Eclipse
The moon orbits(elliptical orbit) around the earth in approximately 27.3 sidereal days(29.5 synodic days).
When the sun, moon and earth get aligned(syzygy) in such a way that moon falls between sun and earth, A solar eclipse happen.
Solar Eclipse associated with new moon phase.
Types of solar eclipse
Solar eclipse can be viewed from very small area on the earth.
In a year, Number of solar eclipse- 2 to 5(max 2 total solar eclipse possible in any year)
Total Solar eclipse- When moon completely block the sun light at some location on earth. Baily's Beads effect(diamond ring effect) is a phenomenon associated with total solar eclipse and annular solar eclipse.
Annular Solar eclipse- When the apparent size of moon is smaller than the sun and sun appears as a bright ring around the moon.
Partial Solar eclipse- When sun and moon are not in a line with earth. In this case moon blocks only partial sun light.
Hybrid Solar eclipse- It is the transition from one type of solar eclipse to another type for a fixed location on earth because of relative motion of Earth and Moon.
Total eclipse → Partial eclipse
Total eclipse → Annular eclipse
Lunar Eclipse
When the sun, earth and moon get aligned and earth is between sun and moon, lunar eclipse take place. Unlike solar eclipse, lunar eclipse can be seen by half part of earth(location where night on earth).
The lunar eclipse phenomenon is associated with Full Moon.
In a year, Number of Lunar eclipse- 2 to 5
Types of Lunar eclipse
Total Lunar eclipse(Blood Moon)- when moon completely lies in earth's Umbra region. In some culture it is described as Blood Moon.
Partial Lunar eclipse- when the moon lies in umbra and penumbra region, it is known as partial lunar eclipse.
PenUmbra Lunar eclipse- when moon lies exclusively in earth's PenUmbra region. In this eclipse the moon surface get dimmed.
Notes-
In solar eclipse, the earth can be in moon's Umbra and AntUmbra region. So Annular solar eclipse is possible.
But in lunar eclipse, moon with small orbital distance can't be in earth's AntUmbra region. So there is no Annular lunar eclipse. The type of lunar eclipse is defined by using Umbra and PenUmbra region only.
Distance of earth and moon < earth's Umbra distance (No Annular lunar eclipse)
Blue Moon-
- 2nd full moon of a month
- 3rd full moon in a season having four full moon
Da Vinci glow
The crescent moon(on horizon) with visible outline of moon because of earthshine at the time of sunset.
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