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The image below might just look like a generic snapshot of the night sky - but hidden in the data is actually a huge nebula spanning most of the picture.

Owing to the limitations of the human eye, we are unable to see the nebula without the image behind enhanced, though.

Now a video has revealed the methods that take place to reveal hidden cosmic features, with colours highlighting some of the details and features that would otherwise be invisible to us.  

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There's a nebula in this image - but you'd be forgiven for not being able to see it. An amateur astronomer has explained in a video how Nasa enhances images of space to reveal features and details that would otherwise be hidden to the human eye. For example, some colours can highlight certain gases and elements

Amateur astronomer Richard Block revealed in a YouTube video how he processed an image of the Rosette Nebula to reveal its stunning hidden detail.

If you were to fly up close to a nebula in a spaceship, it would be pretty disappointing - the dust and gas would not be visible and, save for a few wispy areas, you wouldn't see much.

That's because our eyes are limited in the wavelengths they can see; we are only sensitive to visible light on the electromagnetic spectrum.

Telescopes and cameras are more advanced, though, and they can be used to reveal light in other wavelengths, from X-rays to infrared. 

In his video, Mr Block collected data from the Rosetta Nebula on 1 December 2014 from the Torrance Barrens Dark Sky Preserve in Ontario, Canada.

He took the image using a Canon T3i camera attached to a telescope, and creating the image using PixInsight 1.8. 

The video begins with an ordinary shot of the night sky, complete with thousands of stars, and no discernible nebula in the image.

But a method called 'stretching' then reveals the nebula hidden in the darkest parts of the image.

On Reddit, Mr Block explained what this process entails.

He said if each pixel was said to have a value from 0 to 255, the entire nebula would be in the region 0 to 50 - not visible to the human eye.

'Stretching is taking that 0 to 50 and mapping it across 0 to 255 so that the bright parts of the nebula are the bright parts of the image,' he said.

After stretching the image, he performs some 'noise reduction' to rid the image of superfluous data and then adds some colour to the image, with different colours corresponding to different gases and elements.

He then reduces the sizes of some of the stars so they don't block the view of the nebula, before improving the contrast and creating the final image.

This image shows the intermediate spiral galaxy NGC 3982 before (left) and after (right) colour is added to the image to highlight some of its key features

One of Nasa's most famous images is the Eagle Nebula. On the left is one of three black and white images that were combined to create the final colour version on the right

The Hubble Space Telescope, pictured, uses electronic detectors rather than film like a regular camera to take images of the universe, so data on the images is added after they have been 'taken'

The technique he described is very similar to how Nasa makes its own amazing images.

As explained by Nasa, Hubble records light from the universe with electronic detectors, rather than a film like a regular camera.

The colour is then added at a later date.

'The colours in Hubble images, which are assigned for various reasons, aren't always what we'd see if we were able to visit the imaged objects in a spacecraft,' Nasa said on their Hubble website.

'We often use colour as a tool, whether it is to enhance an object's detail or to visualise what ordinarily could never be seen by the human eye.'