How to safely watch the solar eclipse if you don't have special glasses

Pinhole cameras can get pretty advanced, but NASA's Jet Propulsion Laboratory has instructions for building an incredibly simple version in just a few minutes.

Here's what you need: scissors, tinfoil, a piece of thick card stock (or paper), tape, and a needle.

Cut a hole in the middle of one sheet of card stock, tape the edges of a sheet of tinfoil over it, then carefully pierce the center of the foil with the needle — presto, you've made a pinhole camera. Hover your device over something white, ideally a piece of paper, and move it up and down until you figure out where the ideal focus point is.

You don't even need to even build a contraption — any object with tiny holes that let light through works.

If you happen to be near some kitchen supplies, grab a colander. In addition to straining your pasta, it can project the light from the eclipse onto a piece of paper or cardboard so you can get a glimpse of the effect.

With your back toward the sun, hold the colander over your head and the piece of paper or cardboard out in front of you. You should be able to see the crescent shape from the partial eclipse.

This also works with straw hats and spoons with holes, according to Mark Littmann and Fred Espenak, the authors of "Totality: The Great American Eclipses of 2017 and 2024."

You can also just use your fist. Close your hand tight enough to let only a small point of light through. Hold it up near a surface, and you should be able to see the eclipse projected through the hole.

Never try to look at the sun through binoculars — that's a quick way to blind yourself.

However, you can turn a pair into mini projectors. Just grab a piece of paper, point the binocular's eyepieces toward it, and aim the other end at the sun.

It may help to adjust the binoculars' focal point to create a crisper projection. (Binoculars usually have focus knobs on the eyepieces or central joint.)

Seeing the eclipse is as simple as looking at a tree's shadow. Specifically, find a tree or plant in the sun that has a good amount of leaves and shade. Locate the blobs of sunlight that filter through the leaves.

When the solar eclipse happens, those circles of light should become semicircles — the leaves are nature's equivalent of a pinhole camera. For extra clarity, lay a piece of paper or light-colored cloth down to catch the shadows.

On the off chance you have welder's glass lying around, you can use it to see the eclipse. Welder's glass is designed to protect the eyes of workers from bright bursts of light that acetylene torches give off. That also makes it great to use when looking at the sun, since it blocks most ultraviolet light.

However, the glass has to be dark enough to be effective. NASA recommends shades 12, 13, or 14. (Shade 12 is the least opaque of the three.)

"Many people find the sun too bright even in a shade 12 filter, and some find the sun too dim in a shade 14 filter — but shade 13 filters are uncommon and can be hard to find," NASA's eclipse-safety website says.

The space agency urges extra caution if you want to use an old welder's helmet: "If it's less than 12 (and it probably is), don't even think about using it to look at the sun."

If the weather turns on you or you can't get outside, you'll have to go online — Business Insider has collected and embedded the best livestreaming video feeds around, including those from NASA TV, NASA Edge, Slooh, and more.