Can A Telescope Hurt Your Eyes?

Telescopes are a wonderful invention that everyone should enjoy at some stage in their life.

Although they don’t give you the same experience as the Hubble telescope, a recreational telescope does allow for much better vision than your ordinary pair of binoculars.

Can A Telescope Hurt Your Eyes

They also make it easier to get into space and see what’s going on all around us.

There is no denying telescopes have changed the way we view our world.

However there is always the concern that looking through the lens of a telescope is not the safest thing to do for our eyesight, and one of the most common questions to ask is asking if looking through a telescope can damage our eyes?

What’s the truth behind this statement? Let’s find out.

Can A Telescope Cause Permanent Damage To Your Eyes?

The short answer is no; a telescope will not damage your eyes.

But there is a caveat to this which we will come onto in just a second, as we need a little background on what telescopes actually do.

The first thing to note is what telescopes don’t do. Contrary to popular belief, telescopes don’t make things brighter.

All they do is magnify the dimensions of the object you are looking at, which gives off the effect that the object is brighter when in reality it’s just magnified.

The higher the magnification can go on your telescope, the surface is broader, meaning that the light is no longer focused on one point but distributed over a larger surface area.

With that information in hand, there are some instances where looking through a telescope can damage your eyes.

Solar Light And Eye Damage

Without filters, looking directly at the Sun through a telescope has the potential to damage your eyes.

This is due to the high intensity of direct sunlight. The problem with solar rays is that they contain damaging UV radiation.

UV rays are high-energy electromagnetic waves emitted by energetic particles like those found in the sun.

These wavelengths can cause eye injuries.

An entire family of diseases called “photoreceptor degeneration” are caused by exposure to harmful radiation from solar flares or other sources such as x-rays and gamma rays.

One such experiment was carried out to show the damaging effect staring directly at the Sun through a telescope can have on an eye.

Using an eye from a dead pig, it was placed under the viewing section of the telescope.

After about 20 seconds, smoke started to appear in the eye as it began to burn through the socket.

After having a look at the extent of the damage, a hole was burned through to the retina.

Now whilst most people wouldn’t sit looking directly at the Sun for 20 seconds, it still shows the negative consequences of direct eye contact with the Sun.

This is because a telescope will act as a magnifying glass, causing all of the energy to concentrate on a small point; in this instance the eye socket.

What About Looking At A Full Moon Or Blood Moon?

What About Looking At A Full Moon Or Blood Moon

You won’t have to worry about potential eye damage with a Full Moon or Blood Moon.

This is due to it being a reflection of the Sun’s light, which doesn’t have any significant amount of UV radiation.

As such, it’s safe to stare into the full moon without fear of suffering permanent damage.

One thing to note is that the brightness of a Full Moon can cause the user to have dazzled eyes, which is a short-term side effect for long durations.

Therefore we recommend that a neutral density moon filter is used to reduce the brightness and lower the chances of feeling dazzled.

How To Safely Observe Solar Activity Through A Telescope

Now that we know about the dangers of telescoping viewing, how can we prevent any permanent damage from occurring to us in the long term?

First up, it’s recommended to wear specialized eye protection whenever observing the Sun.

There are many types available, each designed specifically for the type of observation that you’re going to be doing.

For example, while using a large aperture telescope you may want to use something with a high level of UV protection in place.

However, you could also opt for a low-power eyepiece which will filter out much of the UV radiation.

This means that there are ways for you to protect yourself, and hopefully avoid any serious problems with your vision once you’ve stopped gazing into space.

Another important point to remember is the proper precautions that you should take to prevent eye injury.

When aiming a telescope, try to keep your head well away from the tube.

If possible, gaze slightly upward so you don’t have to aim straight ahead.

Make sure to keep your hands away from the eyepiece, otherwise, you’ll increase the chance of any stray movement causing damage.

And last but not least, make sure to wear safety glasses when you do observe anything near the Sun – even if you’re just looking through binoculars!

But one thing to avoid is homemade filters such as compact discs, candy wrappers, or smoked glass as they will not protect the eye from harmful radiation.

What About Stars? Are They Damaging To Stare At?

What About Stars Are They Damaging To Stare At

We’ve covered the Moon and the Sun, but what about stars?

Although stars are just a far-off distant version of our own Sun, they are safe to look at through a telescope.

For example, one of the brightest stars that are visible in the sky is Sirius, which is approximately 8.6 light-years away.

Even though it’s bigger than the Sun, you won’t experience any permanent eye damage, expect a possible unpleasant dazzle that will go away after a little while.

This can be fixed with a neutral density filter to take some of the brightness off.

Final Thoughts

Whilst we want you to enjoy the experience of stargazing and celestial spotting and in most instances, it’s safe to do so, you need to be wary of certain situations that can potentially damage your eyesight if left ignored.

While the far-off stars and our own Moon are safe to look at, the Sun can pose a risk.

Therefore, always wear appropriate eye protection during observations.

In addition, keep your hands clear of the eyepiece as well as keep your gaze pointed downward.

Remember to also have extra filters handy in case you get too bright or too close.

So next time you venture outside to view the night sky, keep these points in mind. Good luck!

Frequently Asked Questions

How Do Telescopes Work?

The purpose of an amateur telescope is simple: to magnify objects on Earth.

It works by sending light towards a lens made of a material called “glass.”

Light passes through the glass where it gets focused onto a piece of “mirror” surface.

When Is The Best Time To Observe The Moon?

It depends on whether you’re planning on sticking around for longer periods.

The answer really varies based on how stable the weather conditions are.

However, generally speaking, mid-to-late-afternoon, when the Moon is higher in the sky, is the best time to watch it, and during the first 6-9 nine days following the new moon.

Can You See the Andromeda Galaxy With Binoculars?

You absolutely CAN see the Andromeda Galaxy with binoculars – although it might appear more like a faint smudge.

But if you were able to use a telescope, you’d be able to view it more clearly – and perhaps pick out details like its spiral arms.

Gordon Watts