Can Telescopes See Through Clouds? (Explained!)

No, telescopes cannot see through clouds. Telescopes may use a magnifying glass that essentially allows us to zoom extremely far out into space however, it does not have the power (right now that is) to look through objects that the human eye cannot. 

For example, a magnify glass wouldn’t allow you to see the through a rock or make our the insides of ball of cotton right?

Therefore the same applies for clouds; if you cannot see through it with the naked eye, a telescope cannot either.

Why Can’t Telescopes See Through Clouds?

To explain why they more in-depth, a telescope cannot see through clouds because it works by reflecting light just like our eyes do. So, if our eyes cannot see through it, a telescope will also be unable to do so.

But why? Because clouds contain water droplets, which light cannot easily pass through. This is what obscures our view of what lies behind the clouds as we (and our telescopes) depend on light reflection in order to see clearly.

Can Telescopes See Planets In Light Pollution?

Light pollution refers to the light generated in urban areas (think of households, skyscrapers, etc.).

Although they won’t be nearly as detailed as the views from a clear sky, a lot of telescopes would still be able see planets in light polluted areas! Venus, Mars, Jupiter, and Saturn are the most easily viewable in this scenario.

What Is The Best Weather To Use Your Telescope?

It’s fairly obvious that the best time to use your telescope is when the weather is clear. But there is a lot more to predicting a clear night sky than just looking at your local forecast.

Often the primary concern when it comes to local weather reports is the likelihood of rain, not if the sky is going to be cloudy or clear.  This is why it’s hard to say even if it’s isn’t raining if the sky would be too cloudy for an optimal stargazing night ahead.

Using resources like Clear Outside or Clear Dark Sky would be the best way to information about local weather and if it’ll suit your stargazing needs. Although barometric pressure is often found in local reports and is a good indicator of how clear the sky is, with higher barometric pressures indicating clearer skies than lower pressures.

There are a couple other factors to consider. These would be transparency and what you can see.

Transparency refers to how clear the sky is, as in how devoid it is of dust and/or humidity. Transparency is at its worst in the summer and best in the winter.

Seeing in stargazing refers to how wobbly the sky seems. This might sound strange, but consider how sometimes when you look up at the night sky, the stars appear to be shimmering or even dancing somewhat. If the sky looks like this, these conditions probably wouldn’t be ideal.

On the other hand, the absence of shimmery stars means the seeing conditions are good.

A general rule of thumb is that seeing is better the later at night it gets, whereas it is at its worst early on.

As can be gathered from this, determining good weather conditions for using your telescope involves multiple factors, but remember that the conditions don’t have to be perfect for a good session. You can stargaze in the summer, it is just that the clarity will likely be lower than it is in the winter months, for example.

Can Radio Telescopes See Through Clouds?

Yes, they can! Note this is a different category of telescope than what has already been discussed.

We have discussed telescopes that work by light, which are known as optical telescopes. Radio telescopes, on the other hand, use radio waves. This type of telescope is able to essentially push through clouds, as well as objects that are normally hidden by dust.

Despite this advantage over optical telescopes, they also have disadvantages.

Radio telescopes have to be a lot larger, or have a much larger viewing area, than an optical telescope in order to provide the same level of detail as it’s optical counterpart. While it can provide images hidden from the optical telescope, it cannot do so with the same level of detail without larger equipment generally.

Optical telescopes are unable to penetrate the clouds, working like our own eyes do. Anything we cannot see through, an optical telescope is also unable to see through.

In this way, it makes sense to think of a telescope as a very powerful magnifying glass, enabling us to see much farther than normal while still being constrained to the visual capabilities our eyes are used to.

On the other hand, radio telescopes can see through clouds, as they function on radio waves, hence their name. In general, they provide a less detailed image than an optical telescope of similar size and viewing area.

The radio telescope needs larger equipment in order to provide the same level of detail as an optical telescope.

Conclusion

Ideal weather conditions to use your telescope are those that have low humidity, high barometric pressure, along with few or no clouds. However, they do not have to be absolutely perfect to be able to stargaze.

In fact, you can even see some planets despite light pollution, meaning you do not have to travel to a remote countryside for a competent experience.

Rather than relying on your local weather station for forecasting, using resources for stargazing is a better option, allowing you to get more detailed information on whether conditions will be favorable for using your telescope.

References

Urban Astronomy

https://www.accuweather.com/en/space-news/the-best-weather-for-stargazing/693840

https://www.opticalmechanics.com/stargazing-conditions/

What is Radio Astronomy?

https://imagine.gsfc.nasa.gov/science/toolbox/emspectrum_observatories1.html