For many people,
viewing a total solar eclipse in person is a once-in-a-lifetime opportunity.
But whether you're a first-time viewer or an avid eclipse chaser,
solar eclipse safety is essential.
It may be tempting to gaze directly at the Sun
or to use your regular sunglasses during these celestial events –
don’t!
Regular sunglasses aren't good enough.
You need proper, solar-safe viewing glasses, or an indirect viewing method,
whenever the bright face of the Sun is visible.
The only time you can look at a total solar eclipse without eye protection
is during the brief period of totality when the Moon completely covers the Sun.
Viewing any part of the Sun's bright disk without protection,
even for a short amount of time, could cause serious eye damage.
One of the most common methods used to view a solar
eclipse is with solar viewing glasses, also known as eclipse glasses.
Eclipse glasses are specifically made to protect your eyes from the Sun's
intense rays and are different from ordinary sunglasses.
Before using any eclipse or solar viewing glasses,
check that they are ISO certified.
If your eclipse glasses appear scratched or damaged,
do not use them as this could result in serious eye injury.
Another easy way to safely view a solar eclipse is with pinhole projection.
This is useful if you don't have access to eclipse glasses or other safe
solar filters, and offers an easy way to quickly view the magic of the eclipse.
There are several techniques you can choose from for this viewing method.
The simplest is to use your hands. With your back to the Sun,
cross one hand over the other with outstretched fingers to create a waffle pattern.
Look at your hands’ shadow on the ground.
The little spaces between your fingers will project a grid of small
images of the Sun – showing the Sun's crescent shape during the eclipse.
You can also see a similar effect
as the Sun shines through holes formed between tree leaves.
The tiny spaces between the leaves act as pinhole projectors,
scattering images of the Sun on the ground!
Anything with small holes, like a hole-punched index card
or even a colander from your kitchen, will work too.
If you're feeling crafty, you can build a box pinhole viewer!
Using everyday household items, this method streams sunlight
through a pin-sized hole to project
an image of the Sun onto a white sheet of paper taped inside the box.
The longer the box, the bigger your image of the Sun will be.
For an even bigger image, you can use optical projection.
This viewing method uses a telescope or binoculars, affixed with a solar filter,
to project the image of the Sun onto a large viewing surface.
This method creates a bigger, brighter and sharper image that
many people can view at the same time.
However,
you should not attempt optical projection unless you are an experienced astronomer
and can supervise your equipment at all times.
Want a closer look? When using a telescope, binoculars, or other optical device,
you must first install a certified solar filter to the front of your instrument –
eclipse glasses can't be used with these devices.
The certified solar filters block most of the sunlight before it enters
the device, safely giving the operator a front-row seat to see the eclipse
in even more detail.
Experiencing a solar eclipse is one way everyone can participate in NASA science.
Now you have the knowledge to participate safely.
Happy eclipse viewing!