Annular eclipse — Tokyo at breakfast (2012)
Tokyo saw its first ring of fire in 173 years — at 7:34 on a weekday morning, watched by tens of millions.
📍 Visible from where you are right now — computed in your browser
bearing · altitude · rise time · best time tonight
The moment of Annular eclipse — Tokyo at breakfast (2012): https://nowsky.org/e/annular-eclipse-2012 — opens at the right place and time, replayable, no login.
Available views: Orbit ✓ · Sky ✓
The story
At 7:34 on the morning of 21 May 2012 a ring of fire rose over central Tokyo. It was the middle of the commute and the school run, and the first annular eclipse seen from the city since 1839 — 173 years. Less an astronomical event than a morning on which an entire metropolis paused.
The shadow started near Guangzhou in southern China, passed just north of Hong Kong and came ashore on southern Kyushu. Inside a band roughly 200 km wide, running through Shikoku, the Kii peninsula, Osaka, Nagoya, Yokohama and Tokyo, lived close to half of Japan's population. The Sun was still low in the east, and the ring stayed closed over Tokyo for about five minutes.
The track then crossed the Pacific to the western United States — Redding in California, Reno, Albuquerque — and ended near Lubbock, Texas, at sunset. Because of the date line, Americans experienced the same eclipse on the evening of 20 May. Few annular paths have threaded so many large cities.
Schools in Japan delayed opening or gathered pupils in playgrounds, eclipse glasses had sold out of convenience stores days earlier, and broadcasters ran live morning coverage. Hokkaido and Tohoku, outside the path, still saw a deep partial of more than 90%. The sky replay shows that Tokyo morning; the orbit view shows the shadow's trans-Pacific track.
Why it matters
The significance was scale rather than science. An estimated eighty million people lived inside the path — among the largest audiences any annular eclipse has ever had. A path over major cities also became a test bed for public safety: how far glasses distribution and broadcast warnings reduce eye injuries was studied afterwards.
There was science too. The National Astronomical Observatory of Japan coordinated simultaneous photography of Baily's beads at both edges of the ring from many sites, a campaign to measure the solar radius; observing the same eclipse from points hundreds of kilometres apart separates the effect of the lunar limb terrain.
2012 was also the year of the 6 June transit of Venus. Within two weeks the same skies offered a day when the Moon covered the Sun and a day when Venus crossed it — an unusually rich spring for observers.
How to watch
The annular track ran from southern China (Guangzhou, north of Hong Kong, in the morning) across Kyushu, Shikoku, Kansai, Chubu and Kanto (Tokyo maximum 7:34), then over the Pacific to northern California, Nevada, Utah, Arizona, New Mexico and Texas on the evening of 20 May. Seoul saw a partial of about 80% that morning.
A morning eclipse sits low, easily hidden by buildings or hills, so an open eastern horizon mattered; a low Sun is no dimmer, and unfiltered viewing is never safe. Despite Japan's extensive safety campaign, more than nine hundred cases of eye discomfort were reported that day.
The sky replay tracks the Sun over Tokyo and slows to the moment the ring closes. Switch the location to Seoul for that morning's partial, or to Albuquerque for the ring of the previous evening.
See this for yourself — open that sky at that moment · replay the moment in the orbit view
Background
The eclipse is a member of Saros 128. Its predecessor, on 10 May 1994, was an annular across the United States; its successor on 1 June 2030 crosses Kushiro in Hokkaido — Japan gets two rings from the same series eighteen years apart.
Tokyo's previous annular, in 1839, fell in the late Edo period and survives in the observation logs of the shogunate's astronomers. The next one for the city is calculated for 2312, which makes the 2012 morning a once-in-centuries chance for the metropolis.
The American section of the path crossed the track of the 14 October 2023 annular in New Mexico, making Albuquerque one of the few cities to see two rings within a single generation.
FAQ
How long did the ring last over Tokyo?
About five minutes, with maximum at 7:34 and the Sun a little over 30 degrees high.
Was it visible from Korea?
Yes — a partial of roughly 80% around 7:30 in Seoul. The ring itself closed only inside the Japanese path.
Why is the US date 20 May?
The same moment falls on the morning of the 21st west of the date line (Japan) and the evening of the 20th east of it (the US).
When is Tokyo's next annular eclipse?
Calculated for 2312. For Japan as a whole, the next ring crosses Hokkaido on 1 June 2030.
Related
- The 2030 annular over Hokkaido
- The 2023 annular over the US West
- The 2012 transit of Venus
- The 2010 annular — longest of the millennium
- The Sun — object index
Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.