Next solar eclipse
Computing eclipse geometry…
—
Times shown in local time.
| Date | Type | Max duration | Visible from here | Coverage here |
|---|
Every number on this site is computed in your browser from first principles. There is no eclipse database behind it, and no API call to fetch.
Because there isn't a good one. NASA/GSFC publishes the authoritative catalogue, but as static pages covering a fixed list of cities. Outreach maps from observatories are images. Xavier Jubier's excellent path files aren't licensed for redistribution. timeanddate.com has the data but no free API. None of them answer the only question that actually matters to you: what happens at my coordinates?
So Umbro carries its own ephemeris and works the geometry out directly. That means it runs offline, costs nothing to serve, and gives the same answer for a mountaintop in Chile as it does for midtown Manhattan.
Solar coordinates come from Meeus's abridged solar theory; lunar coordinates from the truncated ELP‑2000/82 series — sixty periodic terms in longitude and distance, sixty more in latitude. From those two position vectors everything else follows geometrically:
This is the Besselian construction, computed on the fly rather than read from published tables of elements.
Two different numbers get called "how much of the Sun is covered", and they disagree badly. Magnitude is the fraction of the Sun's diameter hidden. Obscuration is the fraction of its area — the one that matches what the sky actually looks like, and the one shown in large type on the front page.
At magnitude 0.5 only about 39% of the Sun's area is gone. Umbro computes obscuration properly from the circle–circle lens area, so a "50% eclipse" here means half the light, not half the width.
Checked against NASA/GSFC's published catalogue for 2017–2030:
Local circumstances, checked against published figures for individual cities:
| Eclipse | Place | Umbro | Published |
|---|---|---|---|
| 2024‑04‑08 | New York | 89.6% | 89.6% |
| 2024‑04‑08 | Los Angeles | 49.2% | 49.1% |
| 2024‑04‑08 | Dallas | 4m07s | 3m52s |
| 2017‑08‑21 | Chicago | 86.7% | 87% |
| 2017‑08‑21 | Casper, WY | 2m28s | 2m26s |
| 2026‑08‑12 | Reykjavík | 1m07s | ~1m05s |
Contact times land within roughly ±30 seconds. That is comfortably good enough to plan a trip around. If you are timing equipment to the second, check NASA/GSFC too.
All the astronomy runs locally. The only things that leave your browser are map tile requests, place searches you type yourself, and — if you don't grant precise location — a single lookup that turns your IP into an approximate city. No accounts, no analytics, no cookies. Your chosen location is kept in your own browser's local storage and nowhere else.
Never look at the Sun without certified eclipse glasses. The only moment it is safe to look with the naked eye is during a total eclipse, between second and third contact, when the Sun's disc is completely covered. During an annular eclipse the photosphere is never fully hidden, so it is never safe — and the same goes for every partial phase of every eclipse. Camera lenses, binoculars and telescopes concentrate the light and will cause injury far faster than the naked eye.
Umbro has no accounts, no analytics, no advertising and no cookies. Almost everything happens inside your own browser. This page lists the exceptions honestly.
All the astronomy — eclipse discovery, shadow geometry, contact times, obscuration, the path of totality and the star background — is computed locally in JavaScript. None of it is sent anywhere.
The location you are using is saved in your browser's local storage under the
key umbra.loc, so the site remembers it next time. It never leaves your device,
and clearing your browser data removes it. A location you picked yourself is kept until you
change it; one that was detected automatically is discarded after 24 hours.
If you allow it, the site reads a precise position from your browser's geolocation API. That coordinate is used for the calculations on the page and stored locally. It is never transmitted to us or to anyone else.
If you don't grant permission, the site instead asks a third-party service to turn your IP
address into an approximate city, so the page has something real to show. That request
necessarily reveals your IP address to whichever service answers. The providers tried, in
order, are ipwho.is, geojs.io and ipapi.co, each under
its own privacy policy. You can avoid this entirely by allowing precise location, or by
typing a place or coordinates into the search box.
There are no other network calls. No trackers, no fingerprinting, no third-party scripts beyond the Leaflet mapping library, which is served as a static file and collects nothing.
The site is hosted on Railway. Like any web host, its infrastructure may record standard request metadata — IP address, timestamp, requested path, user agent — for delivery and abuse prevention. We don't analyse those logs and build no profiles from them.
Nothing here is directed at children specifically, and no personal information is knowingly collected from anyone. If this policy changes, the updated version will simply appear on this page.
Umbro is offered free, as-is, for planning and curiosity. Please read the safety and accuracy sections — they are the ones that actually matter.
Never look at the Sun without certified eclipse glasses or a proper solar filter. The only moment it is safe to look with the naked eye is during a total eclipse, between second and third contact, when the Sun's disc is completely covered. During an annular eclipse part of the photosphere always remains visible, so it is never safe. The same is true of every partial phase of every eclipse. Cameras, binoculars and telescopes concentrate sunlight and will cause injury far faster than the unaided eye; they need filters made for the purpose, fitted in front of the optics.
Do not use the times on this site as your cue to remove eye protection. Use your own eyes and judgement: it is safe only once the Sun's disc is entirely hidden, and you must have protection back on before the first sliver reappears.
Every figure is computed from an abridged ephemeris rather than looked up from an official catalogue. Validation against NASA/GSFC for 2017–2030 puts contact times within roughly ±30 seconds and durations within a few seconds, which is ample for deciding where to travel and when to be outside.
It is not suitable for anything where being a minute out matters: scientific observation, timing equipment, navigation, aviation, or any safety-critical decision. Path edges in particular are approximate, because the calculation ignores terrain elevation and the Moon's irregular limb. If you plan to stand near the edge of the path, verify against NASA/GSFC or your national observatory first.
The site is provided "as is", without warranty of any kind, express or implied, including merchantability, fitness for a particular purpose and non-infringement. To the fullest extent permitted by law, the authors accept no liability for any loss, damage, missed eclipse, wasted journey or injury arising from use of, or reliance on, this site. Your use of it is at your own risk.
There is no guarantee that the site will be available, uninterrupted, or free of errors, and it may change or disappear at any time.
Use the site for any lawful purpose. Please don't hammer it with automated requests, or use it in a way that degrades the third-party services it depends on — Nominatim and the tile servers in particular are volunteer- and donation-funded, and have their own usage policies.