Solar Eclipses in 2021

Two solar eclipses await astronomy enthusiasts in 2021. 

The first is an annular solar eclipse, which is not one that happens every year! Instead, the word annular is derived from annulus, or ring-shaped. The Moon isn’t large enough to cover the entire sun, so it appears to form a hole in the center of it, leaving a ‘wedding band’ in the sky. 

The second solar eclipse of 2021, at the end of the year, is the classic total solar eclipse. In this one, the Moon will completely hide the solar surface, revealing the Sun’s corona and making stars visible in the day. 

This article will guide you through why a solar eclipse occurs in the first place, why they aren’t visible across the entire planet, and what you can expect while chasing the 2021 eclipses. 

A NASA image showing the moon, the Sun and Earth’s alignment for a lunar eclipse
How three celestial bodies should be aligned for a lunar eclipse to occur (Source)

What is a Solar Eclipse?

Solar eclipses are proof that daytime astronomical events can be as beautiful as the night ones. They occur when the Moon’s orbit places it precisely between Earth and the Sun, an alignment called syzygy (pronounced SIZ-eh-gee).

In doing so, the Moon blocks the sunlight, casting a shadow on Earth. If you’re standing in that shadow, you’ll see the Sun obscured to a greater or lesser extent.

Solar eclipses, where the Moon completely covers the Sun, happen due to a perfect coincidence of size and distance.

The Moon is 400x smaller than the Sun but is also 400x closer to Earth. This serendipity makes the lunar disc exactly the same size as the solar one from our perspective.

A solar eclipse begins when the moon makes its first contact, touching a limb of the sun and seeming to take a bite out of the perfect solar circle of light.

The start of a solar eclipse, showing the moon taking a chunk of the sun
The initial phase of a solar eclipse (Source)

When the Sun is not totally covered, the eclipse is a partial one. As the partial eclipse progresses, the bite taken out of the Sun by the Moon grows gradually until the Sun is only a narrow crescent in the sky.

Ten-to-fifteen minutes before totality occurs is when the environment around you begins to change dramatically. There is a noticeable drop in brightness, the shadows grow sharper on the ground, and the sunlight will look strangely different, almost like you’re wearing shades.

A few seconds before the moment of totality, the last vestiges of sunlight peep through valleys between mountains on the Moon, causing the light to break into a thin string of beads, called Baily’s beads.

When totality hits, we instantly see our first glimpse of Sun’s corona, leading to the famous diamond ring effect. This is the stage where darkness takes hold too, making the brighter stars and planets visible in the daytime.

A NASA image showing the solar surface covered by the moon
2017’s total solar eclipse (Source)

While the entire eclipse, from first to the last contact, lasts anywhere between one to three hours, totality itself lasts only for 2-5 minutes

All too soon Baily’s beads and the diamond ring will be visible once again as the moon begins to uncover the sun and the total solar eclipse reverts to a partial solar eclipse.

The disc of the Sun fattens once more as the Moon moves past and the eclipse comes to an end as the Moon’s limb touches the Sun’s in the final act of a solar eclipse, known as last contact.

Why is a Solar Eclipse Not Visible Across the Whole Planet?

The Moon’s shadow is only a few hundred miles across, which is nowhere near large enough to cover the entire Earth. This underlines the fact that you are very fortunate to observe a total Solar eclipse because the strip of Earth they can be seen from is so small.

Furthermore, the fact that only a tiny part of the Earth’s surface experiences an eclipse makes it extremely rare the same place will see a second eclipse within a human lifetime.

The Sun, Moon, and Earth are in constant motion in slightly elliptical orbits. Earth rotates around its axis while the Moon orbits the Earth, and their geometry changes with every eclipse, making it very rare for the same point on the surface of our planet to see consecutive solar eclipses.

What’s The Difference Between The Umbra and Penumbra?

In every eclipse that occurs, there are two shadows cast by the Moon, the inner, darker umbra, and the outer, lighter, penumbra.

It’s easiest to think of the umbra as the shadow we see when the whole Sun is covered, while the penumbra is the shadow caused by a partial covering of the Sun.

As you might imagine, the penumbra has different darkness levels. The part of the penumbra closest to the umbra, where the Sun’s surface might be >90% obscured, is much darker than at its far edge where the Sun is less than 10% covered.

If you stand inside the path of the umbra – also known as the path of totality – the Sun will be entirely blocked by the Moon and you’ll observe a total eclipse.

However, if you stand inside the penumbra during an eclipse, you will only observe it as a partial eclipse.

Of course, some solar eclipses are only partial. When this happens, there is no umbral shadow hitting the Earth’s surface.

Solar Eclipses 2021

There are only two solar eclipses in 2021, with the details set out below.

Annular Solar Eclipse | June 10, 2021

  • Partial eclipse: North of North America, Europe, Asia
  • Annular eclipse: Northern and eastern Canada, Greenland and Russia

The first solar eclipse of the year will be an annular one that lasts from 8:12 UT to 13:11 UT on June 10, 2021

This eclipse will last for only 3 minutes 51 seconds and will cover 94% of the Sun. The Moon is not large enough to cover the entire sun because it will be just 2 days past apogee (furthest from Earth), and will thus be 6.7% smaller than average

Because of this, the Sun’s disk will be visible at the eclipse’s maximum point, and neither the Sun’s corona nor the diamond ring can be seen. 

However, the outer edges of the Sun will be visible all this while, forming the famous ‘ring of fire’.

An image showing a step-by-step occurrence of an annular solar eclipse
An annular solar eclipse with a ring of fire (Source)

The annular eclipse will be visible from Canada, Greenland, and Russia. The path of annularity (shown as the red dot in the gif below) will cross over the North Pole, (the only eclipse to do so in the 21st century) and then move south. 

Viewers in the northeastern United States will see a partial solar eclipse.

A NASA GIF showing the annular solar eclipse’s path
The eclipse’s path (Source)
An image showing the path of annularity for the 2021 annular solar eclipse over Russia
Path of Annularity of the 2021 annular solar eclipse over Russia (Source)
An image showing the path of annularity for the 2021 annular solar eclipse over Canada
Path of Annularity of the 2021 annular solar eclipse over Canada (Source

June 10, 2021 – Annular Solar Eclipse Timings

  • Partial Eclipse Begins: 08:12:15 UTI
  • Annular Eclipse Begins: 09:49:43 UTI
  • Maximum Eclipse: 10:41:51 UTI
  • Annular Eclipse Ends: 11:33:45 UTI
  • Partial Eclipse Ends: 13:11:16 UTI

Total Solar Eclipse | December 04, 2021

  • Partial eclipse: South Africa and South Atlantic
  • Total eclipse: Antarctica

2021’s only total solar eclipse, which will unusually move from east to west over west Antarctica, will only be visible in that region from 5:29 UT to 9:37 UT.

This eclipse occurs 0.1 days before the Moon reaches perigee (the closest to Earth), causing it to be 5.6% bigger than average

The Moon’s large size will cover the sun’s disk entirely, called the totality, for 1 minute 54 seconds. The path of totality is shown by the black ‘smudge’ in the gif below.

A NASA GIF showing the total solar eclipse path
The path of the December 2021 total solar eclipse (Source)

December 04, 2021 – Total Solar Eclipse Timings

  • Partial Eclipse Begins: 05:29:11 UTI
  • Annular Eclipse Begins: 07:00:01 UTI
  • Maximum Eclipse: 07:33:22 UTI
  • Annular Eclipse Ends: 08:06:29 UTI
  • Partial Eclipse Ends: 09:37:24 UTI
An image showing the path of totality over Antarctica
The path of totality of the 2021 total solar eclipse over Antarctica (Source)

Future Solar Eclipses

This table shows all the upcoming total and partial solar eclipses for the rest of the decade. We will, of course, bring much more detail on each one nearer the time.

DateVisibilityType
10 Jun 2021Europe, Asia, Canada and northern USAAnnular
4 Dec 2021South Australia, south Africa, and AntarcticaTotal
30 Apr 2022Southwest South America, AntracticaPartial
25 Oct 2022Europe, southwest Asia, northeast AfricaPartial
20 Apr 2023Southeast Asia, Australia, AntarcticaTotal
14 Oct 2023North and South AmericaAnnular
8 Apr 2024Western UK, North America, northern South AmericaTotal
2 Oct 2024Southern South AmericaAnnular
29 Mar 2025Northwest Europe, Greenland and northeast Canada, northwest AfricaPartial
21 Sep 2025New Zealand and southeastern Australia, AntarcticaPartial
17 Feb 2026Southeast Africa, southern tip of South America, AntarcticaAnnular
12 Aug 2026Much of Europe, north USA and Canada, northeast Asia, northwest AfricaTotal
6 Feb 2027South America and western AfricaAnnular
2 Aug 2027Southwest Europe, southwest Asia, northern Africa, eastern CanadaTotal
26 Jan 2028North and South America, western Europe, and western AfricaAnnular
22 Jul 2028Australia, New Zealand, southern AsiaTotal
14 Jan 2029North AmericaPartial
12 Jun 2029Northern Asia and northern CanadaPartial
11 Jul 2029Southern South AmericaPartial
5 Dec 2029Southern South America and AntarcticaPartial
1 Jun 2030North Africa, Europe, AsiaAnnular
25 Nov 2030Southern Africa, Australia, southern AsiaTotal

Summary

While this post is meant to equip you with knowledge of when the eclipses occur, you cannot completely prepare for the splendor of these cosmic coincidences.

Eclipses give you a chance to watch the solar system at work right in front of your eyes; of the Moon around Earth and Earth around the Sun.

Irrespective of how many times you have seen it, the awe when an eclipse begins, the regret when it ends all too soon, and the ecstasy of witnessing it all cannot be jammed into strings of words. You can only experience it and store the bittersweet memory till the next one comes rolling in.


Written by Sharmila Kuthuner