Solar Eclipse – What is solar eclipse, When and How to See them

Solar Eclipse is very important in the study of the universe, we are going to highlight on what solar eclipse is when and how to see them. From our studies so far A solar eclipse is defined as a spectacular sight and a rare astronomical event. Each one is only visible from a limited area.

Let us consider Solar eclipse under the following heading

The Moon Eclipses the Sun

Types of Solar Eclipses

Solar Eclipses Mainly Look Partial

Solar eclipse around New Moon

Protect Your Eyes- solar eclipse

When and How to See Solar eclipse

The Moon Eclipses the Sun

An eclipse of the Sun happens when the New Moon moves between the Sun and Earth, blocking out the Sun’s rays and casting a shadow on parts of Earth.

The Moon’s shadow is not big enough to engulf the entire planet, so the shadow is always limited to a certain area (see map illustrations below). This area changes during the course of the eclipse because the Moon and Earth are in constant motion: Earth continuously rotates around its axis while it orbits the Sun, and the Moon orbits Earth. This is why solar eclipses seem to travel from one place to another

Types of Solar Eclipses

There are 4 different types of solar eclipses. How much of the Sun’s disk is eclipsed, the eclipse magnitude, depends on which part of the Moon’s shadow falls on Earth.

1. Partial solar eclipses occur when the Moon only partly obscures the Sun’s disk and casts only its penumbra on Earth.
2. Annular solar eclipses take place when the Moon’s disk is not big enough to cover the entire disk of the Sun, and the Sun’s outer edges remain visible to form a ring of fire in the sky. An annular eclipse of the Sun takes place when the Moon is near apogee, and the Moon’s antumbra falls on Earth.
3. Total solar eclipses happen when the Moon completely covers the Sun, and it can only take place when the Moon is near perigee, the point of the Moon’s orbit closest to Earth. You can only see a total solar eclipse if you’re in the path where the Moon’s casts its darkest shadow, the umbra.
4. Hybrid Solar Eclipses, also known as annular-total eclipses, are the rarest type. They occur when the same eclipse changes from an annular to a total solar eclipse, and/or vice versa, along the eclipse’s path.

Solar Eclipses Mainly Look Partial

Solar eclipses are only visible from within the area on Earth where the Moon’s shadow falls, and the closer you are to the center of the shadow’s path, the bigger the eclipse looks.

Solar eclipses are usually named for their darkest, or maximum, point. The exception is the hybrid eclipse.

The darkest point of solar eclipses is only visible from a small area. In most places and for most of the duration, total, annular, and hybrid eclipses look like a partial solar eclipse.

Solar eclipse around New Moon

For a solar eclipse to take place, the Sun, the Moon, and Earth must be aligned in a perfect or near perfect straight line–an alignment astronomers call syzygy. This happens around New Moon every lunar month.

So, why isn’t there a solar eclipse every New Moon night?

There are 2 reasons:

1. The New Moon has to be near a lunar node. These nodes are 2 points where the plane of the Moon’s orbital path around Earth meets Earth’s orbital plane around the Sun–the ecliptic. The paths meet because the plane of the Moon’s path around Earth is inclined at an angle of approximately 5° to the ecliptic.
2. The Sun must also be close to a lunar node so it can form a perfect or near-perfect line with the Moon and Earth. This alignment occurs a little less than 6 months apart, and it lasts, on average, around 34.5 days. It is only during this time–the eclipse season–that eclipses can take place.

When there is a Full Moon during the eclipse season, we see a lunar eclipse.

Different types of solar eclipses

Protect Your Eyes!

Never look directly at the Sun, eclipsed or otherwise, without any protective eyewear. The Sun’s UV radiation can burn the retinas in your eyes leading to permanent damage or even blindness.

The best way to safely watch a total solar eclipse is to wear protective eclipse glasses or to project an image of the eclipsed Sun using a pinhole projector.

When and How to See Solar Eclipse

In 2019, skywatchers in a few select locations on Earth will have three opportunities to see a solar eclipse, a celestial event in which the moon briefly appears to take a bite out of the sun.

A solar eclipse occurs when the disk of the moon appears to cross in front of the disk of the sun. A total solar eclipse — like the one that crossed the U.S. on Aug. 21, 2017 — occurs when the disk of the moon blocks 100 percent of the solar disk. A partial eclipse occurs when the moon covers only part of the sun. If the moon passes directly in front of the sun when it is near apogee, the point in its elliptical orbit where it is farthest from Earth, skywatchers will see an annular eclipse, also known as a “ring of fire.”

On Jan. 5 to 6, 2019, a partial eclipse will be visible from northeast Asia and the north Pacific. A total solar eclipse will follow on July 2, and it will be visible almost exclusively over South America. Last but not least, an annular solar eclipse will occur over Saudi Arabia, India and southeast Asia on Dec. 26, and it will appear as a partial eclipse over Asia and Australia. You can see a complete list of the upcoming solar eclipses on NASA’s website, which provides information about solar eclipses, including detailed maps of each eclipse path. [Solar Eclipses: An Observer’s Guide (Infographic)]

Partial solar eclipse on Jan. 5-6

The first solar eclipse of the year will be of the partial variety, which means that the moon will block only a portion of the sun. During a partial solar eclipse, it looks as though the moon is taking a “bite” out of the sun’s disk.

This eclipse will begin on Jan. 5 at 6:34 p.m. EST (2334 GMT), when the moon will first appear to make contact with the sun’s disk. It will start near Beijing and slowly move northeast toward Alaska, where only the state’s westernmost islands will be able to see the eclipse before the sun sets.

The table below shows the times when the eclipse will reach its maximum for a few major cities, as well as the maximum obscuration, or the percentage of the sun’s disk that will be covered by the moon. You can also look up the details for any location using an eclipse calculator like this one from eclipse expert Fred Espenak, aka “Mr. Eclipse,” or this interactive map by timeanddate.com.

The total solar eclipse on July 2

Nearly two years after the Great American Solar Eclipse of 2017, the world will once again have a chance to experience totality, when the moon completely blocks the sun, turning day into night as its 125-mile-wide (200 kilometers) shadow moves across the surface of the Earth.

On July 2, 2019, the moon will block the sun over the South Pacific Ocean, Chile and Argentina. Other parts of South America will be able to see a partial eclipse. Most of this eclipse will be happening over the Pacific Ocean, where the partial eclipse starts at 12:55 p.m. EDT (1655 GMT).

This total solar eclipse will have a longer duration than last year’s total solar eclipse, with totality lasting up to 4 minutes and 33 seconds. However, this maximum duration may be visible only to observers on a few boats and airplanes, because it will be happening over the Pacific Ocean.

Totality will first make landfall over Oeno Island, a British territory in the South Pacific Ocean, at 10:24 a.m. local time (1824 GMT). It will reach the coast of Chile near the city of La Serena at 4:39 p.m. local time (1939 GMT). Moving southeast, the moon’s shadow will cross the Andes mountains and graze San Juan, Argentina, which lies just inside the path of totality. It will barely miss Cordoba and Buenos Aires, Argentina, as well as Montevideo, Uruguay, passing just south of these three cities before heading back out to the Atlantic Ocean just before sunset at 5:40 p.m. local time (2040 GMT).

The table below shows the start, peak and end times of the eclipse for a few cities in and around the path of totality, as well as the maximum obscuration, or the percentage of the sun’s disk that will be covered by the moon.

You can also look up the details for any location using this interactive map by timeanddate.com.

Annular eclipse on Dec. 26

The third and final solar eclipse of the year will be a “ring of fire” eclipse on Dec. 26, and it will be visible from Saudi Arabia, Qatar, India, Sumatra, Borneo, Guam, and the Philippines. Skywatchers in other parts of Asia, Australia, and Africa will be able to see a partial eclipse.

During this eclipse, the moon will cross directly in front of the sun. However, because the eclipse occurs just a few days after the moon reaches apogee — its farthest distance from Earth — its apparent size in the sky will be smaller than the sun. This means that it won’t block the sun entirely, but it will instead turn the sun into a blazing “ring of fire” from Earth’s perspective.

The first location to see the annular eclipse is 137 miles (220 km) northeast of Riyadh, Saudi Arabia, according to Espenak’s website EclipseWise.com. It will begin there at 6:34 a.m. local time (3:34 GMT), and it will last 2 minutes and 59 seconds. Guam will be the last place on Earth to see the eclipse. The island will see the annular eclipse last for more than 3 minutes, and the sun will set before the partial phase of the eclipse has ended.

You can look up visibility information for any location using this interactive map by timeanddate.com or Espenak’s eclipse circumstances calculator.

How to view the sun safely

WARNING: Looking directly at the sun, even during an annular eclipse, can lead to blindness and other forms of permanent eye damage if you aren’t wearing proper eye protection.

To safely observe the sun or watch an eclipse, you need special protective eyewear or eclipse glasses. Basic sunglasses, even those with UV protection, will not sufficiently protect your eyes. If you’re planning to document the eclipse with any photo equipment, there are special solar filters you can add to make sure the remaining ring of sunlight doesn’t take a toll on your vision.

The safest way to observe an eclipse is indirect, using a pinhole camera that you can make easily at home.