How to Watch a Solar Eclipse Safely, and When the Next Ones Are
A solar eclipse is one of the few sky events where safety comes before everything else. Unlike a lunar eclipse, which you can watch with bare eyes, a solar eclipse means looking toward the Sun. NASA's eclipse safety page is direct about it: except during the brief total phase of a total solar eclipse, "it is not safe to look directly at the Sun without specialized eye protection for solar viewing."
Below are NASA's safety rules, the kinds of solar eclipse, and NASA's list of eclipses from 2027 through 2030.
1. The four kinds of solar eclipse
NASA Goddard's eclipse tables, prepared by Fred Espenak, sort every solar eclipse into four types:
- Total: the Moon completely covers the Sun's bright face along a narrow path.
- Annular: the Moon is too small to cover the Sun, leaving a bright ring.
- Hybrid: total along part of its path and annular along another.
- Partial: the Moon covers only part of the Sun everywhere it is seen.
The tables also explain why total and annular eclipses differ. The "eclipse magnitude" listed for each one is the ratio of the Moon's apparent diameter to the Sun's. For total eclipses it is 1 or more; for annular eclipses it is always less than 1.
2. Rule 1: use real eclipse glasses or a solar viewer
For partial and annular eclipses, and for the partial phases of a total eclipse, NASA says you must look through safe solar viewing glasses or a handheld solar viewer at all times.
- Sunglasses are not enough. NASA says regular sunglasses, no matter how dark, are not safe for viewing the Sun. Safe solar viewers are thousands of times darker.
- Check the standard. NASA says safe viewers ought to comply with the ISO 12312-2 international standard. NASA does not approve any particular brand.
- Inspect them first. If they are torn, scratched, or otherwise damaged, throw them away.
- Supervise children whenever they use solar viewers.
3. Rule 2: never combine glasses with optics
This is the mistake that causes the worst injuries. NASA warns: do not look at the Sun through a camera lens, telescope, binoculars, or any other optical device while wearing eclipse glasses or using a handheld viewer. The concentrated light "will burn through the filter and cause serious eye injury."
If you want to use binoculars, a telescope, or a camera, it needs its own special-purpose solar filter attached to the front of the optics. With that filter properly fitted, NASA says you do not also need eclipse glasses. NASA recommends getting expert advice from an astronomer before using a solar filter on any optical device.
4. Rule 3: no glasses? Project the Sun instead
NASA describes indirect viewing methods that never involve looking at the Sun:
- Pinhole projector: punch a small hole in an index card, stand with the Sun at your back, and let the sunlight fall through the hole onto a nearby surface. Look at the image, never through the pinhole.
- Colander: during the partial phases, the round holes of a kitchen colander project small crescent Suns onto the ground.
- Box projector: NASA explains how to make one from a cardboard box, white paper, tape, scissors, and aluminum foil. Sunlight enters through a pinhole in the foil and projects a crescent Sun onto the paper inside, which you view through another hole in the box.
5. Rule 4: totality is the only exception
During a total solar eclipse, NASA's guidance is:
- Wear eclipse glasses or use a viewer during the partial phases before totality.
- Look with unprotected eyes only when the Moon completely covers the Sun's bright face. You will know it is safe when you can no longer see any part of the Sun through your eclipse glasses.
- As soon as even a little of the bright Sun reappears, put your glasses back on or go back to your viewer.
During an annular or partial eclipse there is no such moment. The ring of an annular eclipse is still the bright Sun.
6. Rule 5: protect your skin too
NASA notes that you may be in direct sunlight for hours while watching a whole eclipse, and recommends sunscreen, a hat, and protective clothing.
7. Upcoming total and annular solar eclipses
These come from NASA Goddard's 2021 to 2030 table. Dates are for the moment of greatest eclipse on a global time standard, and the duration is the length of totality or annularity at the point of greatest eclipse. Places listed are inside the central path; a partial eclipse is visible over a much wider area.
| Date | Type | Central duration | Central path crosses |
|---|---|---|---|
| Feb 6, 2027 | Annular | 7 min 51 s | Chile, Argentina, Atlantic |
| Aug 2, 2027 | Total | 6 min 23 s | Morocco, Spain, Algeria, Libya, Egypt, Saudi Arabia, Yemen, Somalia |
| Jan 26, 2028 | Annular | 10 min 27 s | Ecuador, Peru, Brazil, Suriname, Spain, Portugal |
| Jul 22, 2028 | Total | 5 min 10 s | Australia, New Zealand |
| Jun 1, 2030 | Annular | 5 min 21 s | Algeria, Tunisia, Greece, Turkey, Russia, northern China, Japan |
| Nov 25, 2030 | Total | 3 min 44 s | Botswana, South Africa, Australia |
The table also lists four partial solar eclipses in 2029 (January 14, June 12, July 11, and December 5), with no total or annular eclipse that year. NASA lists the January 14, 2029 partial eclipse as visible from North and Central America, and the June 12, 2029 one from the Arctic, Scandinavia, Alaska, northern Asia, and northern Canada.
The August 2, 2027 eclipse stands out. Its 6 minutes 23 seconds of totality is the longest total phase in this list (the January 2028 annular eclipse lasts longer, at 10 minutes 27 seconds), and its path crosses southern Spain and North Africa.
8. Key takeaways
- Never look at the Sun without proper solar protection, except during totality of a total solar eclipse.
- Eclipse glasses should meet the ISO 12312-2 standard; regular sunglasses are never safe.
- Never use binoculars, a telescope, or a camera while wearing eclipse glasses; optics need their own front-mounted solar filter.
- Pinhole projectors and colanders let you watch the partial phases without looking at the Sun.
- NASA lists total solar eclipses on August 2, 2027, July 22, 2028, and November 25, 2030.