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Annular Solar Eclipse of 2020 June 21
from Saudi Arabia, Oman, India or Tibet (China)
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To observe the 2020 June 21 annular eclipse, I will likely travel to Oman because it’s the perfect choice both for the weather and the beauty of the country or else to the Tibetan plateau where the higher elevations will provide more enjoyable temperatures and a very slightly increased magnitude. Trying to view a deeper and nearly pearled annular, and yet not even close to ASE 1966 in Greece, from the summit of the Hardeol peak (Temple of God) at 7,151 meters (23,461 feet) in India is enticing although the odds of succeeding are far too low because of the extremely high elevation, technical climb challenges, remoteness and pre-monsoon potentially unstable weather; moreover to this date this peak has only been climbed twice. In the end Tibet could be the more balanced option enabling the eclipse chasers to avoid torrid heat and airborne dust, knowing that no matter what the apex/tip of the umbral shadow cone is about 2,300 kilometers above and as such well out of reach. In the end observers in India and Tibet, where the eclipse path is at its narrowest, can nearly expect to have a view quite similar to the one of ASE 1984 across the USA east coast. On the other hand, observers located earlier or later inside the eclipse path will get a slightly lower magnitude and hence a marginally thicker ring.
The visual appearance, through solar filters unless near sunrise or sunset, of this deep annular solar eclipse will be similar to the February 1999 annular.
Covid-19 Update: because of the novel coronavirus pandemic we were not able to travel abroad and did have to cancel all our plans. In the end only residents of the countries crossed by the path of annularity got to experience this thin ring. Such a shame we couldn’t travel for this unique eclipse! My personal experience was even worse as I was already traveling in Argentina during the mid-March lockdown and had to exfiltrate myself only to be on partial unemployment back in France and two days before the annular laid off with 15% of the staff at the headquarters in a social plan despite a 22-year seniority (as one can imagine the company’s executives just took the opportunity even though there was no reason to act so quickly and without any prior consultation as the state was paying our salaries)!
You can use this solar eclipse calculator to compute the local circumstances of the eclipse, and the solar eclipse timer notifies the beginning of the various events. A time exposure calculator is there to help you choose your camera settings.
Click on thumbnails for a larger version
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Observing an annular solar eclipse can be done in multiple ways: for example having the annular phase at sunrise or sunset in order not to use any solar filter, or from the center of the eclipse path to get a symmetrical ring, or else near the edges of the eclipse path to get more Baily’s beads and for a longer duration with the additional benefit to be able to also photograph the chromosphere (be careful as this very last option is potentially dangerous for your eyesight and equipment).
The general and most frequent circumstance is an observation from inside the eclipse path with a Sun high enough, say five to ten degrees and above. For this type a solar filter is mandatory, just like it is with a partial solar eclipse or else viewing the Sun outside of an eclipse.
Lets now move on to more "advanced" observations.
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An observation at sunrise or sunset allows to do without any solar filter as long as the Sun is sufficiently low. However this type of observation is more risky as you need a perfectly clear sky on the horizon, something harder to get than when near the zenith. On December 26, 2019, I went for a premiere during the annular at sunrise in Saudi Arabia. The goal was to be able to view naked eye and image the annular phase at about one degree above the horizon without any solar filter. It also permitted to view the reddish chromosphere naked eye just before second contact, and this is most likely a world premiere during an annular. Moreover the simulations made using my Solar Eclipse Maestro software perfectly match with the observations.
Picture taken without solar filter, about 6 seconds before second contact, by Xavier Jubier from the Devil’s Thumb near Judah in Saudi Arabia
(reddish chromospheric arc are clearly visible)
Picture taken without solar filter, about 2 seconds before second contact, by Xavier Jubier from the Devil’s Thumb near Judah in Saudi Arabia
(Baily’s beads and chromosphere are visible)
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Viewing an annular solar eclipse from the northern or southern limits can be more rewarding than from the centerline. However to maximize your experience and lengthen the duration of the Baily’s beads you need to be positionned properly. Two main options are therefore possible: the first is to get both some short annularity time with prolonged beads or else only prolonged beads by staying in the grazing zone and optimized chromospheric photography for the more adventurous. In both cases the chromosphere can be photographed by not using any solar filter at the proper time (CAUTION, THE LATER PRACTICE IS DANGEROUS AND YOU SHOULDN’T LOOK NAKED EYE).
The following pictures were taken during the February 1999 annular from the Western Australia coast. You can see the simulations match the pictures quite well although those were done at low resolution. Observers who wanted to have both a complete ring and a nice display of Baily’s beads had to be well inside the path by about 8 kilometers, the village of Greenough being indeed barely qualified: some of them decided to go a few kilometers to the south to be on the safer side. Similar pictures can again be taken during this annular eclipse.
Beads and chromosphere can be seen on all the pictures that were taken without any solar filter. Note: not using any proper solar filter is not recommended unless you know exactly what you’s doing. If you are not experienced then please DO NOT ATTEMPT this and DO NOT LOOK THROUGH THE OPTICAL VIEWFINDER OR ANY OTHER OPTICAL DEVICE WITHOUT A SOLAR FILTER.
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Picture taken without solar filter, about 13 seconds before second contact, by Fred Espenak from Greenough in Western Australia
Picture taken without solar filter, about 12 seconds after third contact, by Fred Espenak from Greenough in Western Australia
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Picture taken without solar filter, about 9 seconds before second contact, by Fred Espenak from Greenough in Western Australia
Picture taken without solar filter, about 11 seconds after third contact, by Daniel Fischer from Greenough South in Western Australia
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Now the February 2017 annular from Argentina at the southern edge without any solar filter. Once again the simulations closely match the photographs and an accurate solar diameter measurement is possible.
Pictures taken without any solar filter, between second and third contacts, by Jörg Schoppmeyer from Sarmiento in Argentina
Still the February 2017 annular from Argentina but this time near the centerline without any solar filter.
Sequence taken without any solar filter, at second and third contacts, by Petr Horálek from Facundo in Argentina
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This annular solar eclipse is deep, which means its visible solar ring will be extremely thin, and the eclipse path is also narrow at a little more than 20 kilometers (12 miles) in India and Tibet (China) where the eclipse magnitude is the highest, up to more than 80 kilometers at both ends.
After carefully studying the lunar limb profile and looking at the map of the various locations near the edges of this annular eclipse path, here are my main three recommendations:
- first if you choose to aim for the northern limit in India or Tibet, then do make sure you position yourself at an ant-umbral depth of at least 56% (please refer to my eclipse map) to have both prolonged beads and a couple seconds of true annularity; if you go closer to the northern edge you’ll only get prolonged beads but the eclipse will never become truly annular. This translates to about 6 kilometers along the whole eclipse path.
- second if you target the southern limit, then do make sure you you position yourself at an ant-umbral depth of at least 30% (please refer to my eclipse map) to get both prolonged beads and a couple seconds of true annularity. This translates to about 3 kilometers along the whole eclipse path.
- last make sure you take into account the elevation of your viewing location as it can slightly shift the eclipse path, particularly at low solar elevations.
If you choose to be inside the grazing zone, that is closer to the edges of the eclipse path, then you will maximize the prolonged beads without any true annularity time.
On my side I will attempt annularity close to greatest eclipse from the high elevations of the Tibetan Plateau increasing a tiny bit more the eclipse magnitude.
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