he wild year of 2020 otherwise. And although I don’t keep in con- boasted two solar eclipses: stant contact with every one of them, when an annular eclipse on June an eclipse passes overhead anywhere in the 21 and a total solar eclipse world, I have a good chance of hearing from on December 14. Travel some of my old friends who are eager to restrictions prevented share their new pictures. North Americans, as well At the time of this writing, the next solar Tas many others in the Western Hemisphere, eclipse to be seen from Earth will be total, from viewing the path of annularity that with its peak occurring near the Argentina/ stretched from Africa through the Middle Chile border on December 14, 2020. Be sure East to Pakistan, India, mainland China, and to keep an eye out for images of December’s Taiwan. Fortunately, local eclipse viewers total solar eclipse in future issues of who managed to get beneath the Moon’s Astronomy. Corona shadow captured wonderful images of the Meanwhile, the next annular eclipse will breathtaking event. be on June 10, 2021. Its path will trek from The following is a smattering of shots southern Canada over the North Pole and from last June’s annular eclipse, which I down to the Russian Far East. Observers in monitored into the wee hours of the morn- the northeastern United States will be happy ing with the help of email, the web, and to learn that partial phases of this annular livestreams from the Middle East and Asia. eclipse will be visible to them in the early My decades-long interest in eclipses, and the morning. So, make sure to get your filtered resulting expeditions I have taken to view solar eclipse glasses now, available at Light them, have allowed me to meet many fasci- MyScienceShop.com. nating people who I never would have And don’t forget: Share what you see! Missed last year’s annular eclipse? We’ve got you covered with some of the best shots out there. A RINGED ECLIPSE The word annular comes from annulus, which means “ring.” So, when the Moon is just far BY JAY PASACHOFF enough away from Earth that it leaves the outer perimeter of the Sun’s disk unobscured, the result is often referred to as a “ring-of-fire” eclipse. At maximum coverage, this outer band of sunlight is up to a few percent of the solar disk’s diameter. So, technically, it could be called a The Mango Education Group “ring-of-photosphere” or a “ring-of-sunlight” eclipse. experienced annularity during The term “ring-of-fire” has murky origins dating back at least 150 years, but its current clear weather from Dehradun, usage in reference to annular eclipses dates has been around for at least a few decades, when the winter capital and most pop- ulous city in the Indian state of it started popping up various publications. However, “ring-of-fire” is somewhat misleading ter- Uttarakhand. That fortunate minology, and it is disliked by many professional and amateur astronomers, or so-called weather allowed them to capture umbraphiles (an umbra is the dark part of a shadow). Contrary to common conception, there is this crisp shot of the thin circle no chemical fire on the Sun. Rather, we owe the warmth and light we receive from the Sun to created by the Sun’s disk stretch- the clean thermonuclear fusion of hydrogen gas safely occurring some 93 million miles (150 ing out just beyond the Moon’s million kilometers) away. silhouette. HARINDRA BARAIYA (WILDLIFE INSTITUTE OF INDIA/MANGO ASTRONOMY CLUB); IMAGE FORWARDED BY STEPHEN INBANATHAN (AMERICAN COLLEGE IN MADURAI)

Right: On June 21, the Moon was relatively far from Earth in its elliptical orbit, so its angular size was smaller than usual. Therefore, it couldn’t fully block the solar disk when the Sun, Moon, and Earth aligned, or entered syzygy, as shown in this artist’s illustration. ERNEST T. WRIGHT, NASA’S GODDARD SPACE FLIGHT CENTER SCIENTIFIC VISUALIZATION STUDIO

IMAGES: JAY PASACHOFF; COMPOSITE: MUZHOU LU

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After the Moon’s Rafay Kazmi, a student at 1 shadow first touched the 4 Williams College in Republic of Congo during the June Williamstown, Massachusetts, 21 annular eclipse, it departed observed a partial eclipse from his Africa, went through the Middle home in Islamabad, Pakistan. Here, East, then passed through southern he and his sister are seen viewing Pakistan, northern India, mainland the eclipse through special solar fil- China, and Taiwan before vanishing ters, one of thousands left over from southeast of Guam. The annular the 2017 Great American Eclipse eclipse path, which stretched 9,058 and available through Astronomers miles (14,578 km) was just 13 miles Without Borders. RAFAY KAZMI (21 km) wide and maximum eclipse (99 percent) lasted about 38 sec- Clouds only served to add mys- onds. MICHAEL ZEILER AN UNFILTERED VIEW LEADS TO A REVISION 5 tique to this view of the eclipse from the city of Sirsa in the northern The path of annularity during Indian state of Haryana, taken by 2 the June 21 eclipse grazed The June 21 annular tain a website at the easiest possible address to Neelam and Ajay Talwar. Saudi Arabia, resulting in a partial eclipse also remember: eclipses.info. The working group also NEELAM & AJAY TALWAR eclipse for many. Abouazza Elhamdi traced a path acts as a clearing house for professionals pursuing This series of images, showing of the Astronomy and Physics through international eclipse expeditions, coordinating such Department of King Saud University 6 the partial eclipse as seen from captured this sequence of partial Pakistan, where matters as visas, customs, and the shipping of Coimbatore, a city in the south phases in the early morning from the cloud-cover equipment. Indian state of Tamil Nadu, was Riyadh, Saudi Arabia. I am working forecast was For the above image, Zia and Kentrianakis for- captured by members of the Mango with Abouazza and colleagues from not as favorable went filters in order to capture detailed views of Astronomy Club. OBULI CHANDRAN Saudi Arabia, atmospheric physicist as in the lower Baily’s beads, which occur when sunlight peeks The Talwar team also captured Marcos Peñaloza-Murillo of Arabian Peninsula. through valleys along the lunar limb. This allowed Venezuela, and Michael Roman of 7 this series of images tracking England to analyze how eclipse Fortunately, it them to successfully detect the solar chromo- the progress of the annular eclipse darkening impacts the local temper- turned out to be very sphere, and even the inner solar corona. over Sirsa. Even through the clouds, ature and humidity in that desert clear. Prior imaging of Baily’s beads taken during pre- one can identify Baily’s beads, the climate. ABOUAZZA ELMHAMDI From Sukkur — a city in the Pakistani province vious total solar eclipses led to discussions solar chromosphere, and, perhaps, of Sindh — Talha Moon Zia, who is a research between me, Xavier Jubier, and Ernest T. Wright of even glimpse the solar corona. NEELAM & AJAY TALWAR LEFT: Unlike central Saudi astronomer at Pakistan’s National Center for Big NASA’s Scientific Visualization Studio. We con- 3 Arabia, Izki, Oman, did see annularity. Alaa Ibrahim and Zach Data and Cloud Computing/NED University of cluded that the IAU’s nominal solar diameter — the Ioannou of the Astronomy Group at Engineering & Technology, obtained these wonder- defined size of the Sun’s photosphere, which is Sultan Qaboos University captured ful unfiltered views of the annular eclipse. The shots used for predicting the length of eclipse totalities 6 a series of images with the aid of a above were created by stacking several short-expo- down to a fraction of a second — needed a minor hydrogen alpha filter, including the sure images and were taken under the guidance of revision. By comparing our observations to simula- single short exposure seen here. A. Michael Kentrianakis, the former project manager tions from Jubier’s website of the expected Baily’s IBRAHIM/Z. IOANNOU RIGHT: The view of the annular of the American Astronomical Society’s 2017 U.S. beads for this eclipse, which were based on high- eclipse at right was created by eclipse efforts and a member of our resolution 3D mapping of the lunar sur- stacking 210 images, which International Astronomical Union’s face obtained by NASA’s Lunar 7 revealed some notable solar promi- (IAU) Working Group on Solar Reconnaissance Orbiter and the nences, or bright tendrils of plasma Eclipses. Japanese Kaguya mission, our anchored to the Sun’s surface (pho- tosphere) that extend into the Our IAU group focuses on suspicions were confirmed. corona. The observers also tracked being a central resource for The true size of the Sun’s the ambient temperature and anyone looking to find out more photosphere is a slightly humidity of their site throughout the about past or upcoming solar larger than previously thought. event. Before the eclipse, they eclipses. To do this, we main- reported it was 113 degrees BOTH IMAGES: NCBC-NEDUET Fahrenheit (45 Celsius), which WWW.ASTRONOMY.COM 43 11

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Many observers who were unable to personally see the annular eclipse dim the skies during the daytime instead opted to monitor images and livestreams of the event aired during the middle of their local night — an option not available to eclipse enthusiasts just a few decades ago. Now, worldwide communication and online eclipse- mapping tools, like those from Xavier Jubier of France (http://xjubier.free.fr/ase2020map) and retired astro- physicist Fred Espenak (EclipseWise.com), provide detailed eclipse data for any location on Earth. Additionally, cartographer Michael Zeiler of New Mexico has meticulously created high-quality eclipse maps, while cloudiness statistics over the decades have been gleaned and put into context by Jay Anderson of Canada. (Anderson and I jointly authored the Peterson Field Guide to Weather, which is being published in summer 2021.) All of these resources are linked on the website for the International Astronomical Union’s Working Group on Solar Eclipses (http://eclipses.info), which I chair. Additionally, observations of the 75 or so solar eclipses I worked on in the past are posted to the Williams College Eclipse Expeditions website (https://sites.williams.edu/ eclipse).

A camera mounted to the 11 outside of the International 10 Space Station captured this shot of the Moon’s shadow racing across Earth (near the border of Kazakhstan and China) during the June 21 annular eclipse. A Japanese cargo spacecraft is visi- ble in the foreground. NASA/ISS EXPEDITION 63

9 The X-ray telescope on the 12 Japanese Hinode space- craft captured this series of shots, Amateur astronomer Zhou of the Sun’s disk being blocked 8 Guanhuai (left), who had previ- out by the Moon during the June ously corresponded with the author 2020 eclipse, which have been about earlier eclipses, sent an 12 rescaled and colored. Astronomer image (right) of the partial eclipse Taro Sakao of the Japan as seen from Jinan, Shandong prov- Aerospace Exploration Agency ince, China. Here, the partial eclipse 13 (JAXA) took advantage of reached its greatest coverage at Hinode’s vantage point to observe 15:55 local time with a magnitude of how plasma moves in the high- 0.67. CREDIT: ZHOU GUANHUAI speed solar wind stream, using Jay Pasachoff is Field the lunar silhouette for calibration Near the end of the path of of stray light. JAXA/HINODE (THANKS TO 9 annularity in Guam, the eclipse Memorial Professor of ALPHONSE STERLING OF NASA’S MARSHALL SPACE was visible with 97 percent cover- Astronomy at Williams FLIGHT CENTER, AND KATHY REEVES AND LUCAS age, as seen in this eerie photo GULIANO OF THE HARVARD-SMITHSONIAN CENTER taken by Dean Patrick Servito. The College in Williamstown, FOR ASTROPHYSICS.) path of annularity continued about Massachusetts, and 50 miles (80 km) out to sea – briefly The passage of the Moon’s tempting me to fly to the U.S. terri- chair of the International 13 shadow across Earth’s tory for a quarantined glimpse from Astronomical Union’s surface was tracked by the a boat. DEAN PATRICK SERVITO European Meteosat-8 and the Working Group on Solar Japanese Himawari-8 spacecraft. Due to travel restrictions Eclipses. He has worked Here we see a Meteosat view of 10 related to the COVID-19 on 75 solar eclipses and Moon’s shadow over northeast pandemic, I was unable also to ven- Africa, the Red Sea, and the ture to Europe. These images came written about the Sun for Arabian Peninsula. The antumbral from Thessoliniki, Greece. They Astronomy since its very shadow (the lighter part) first were captured by Aris Voulgaris, touched Earth in Congo. with whom I closely work on total first issue. COPYRIGHT 2020 EUMETSAT solar eclipses. ARIS VOULGARIS

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