Image Data


An image of a galaxy

An digital image of a galaxy

An image of a galaxy with a magnified area showing the individual little squares or pixels. The colours are false.
Astronomers take images with large professional telescopes because they want to use them to do some scientific research. They therefore need to be able to make measurements, such as the brightness of a star or the position of a planet.

This means that the images are not just pictures, but large amounts of data.

This data is usually stored on computers in special files and can be very large - a typical image data file from the Liverpool Telescope will have more than 4,000,000 (4 million) numbers in it!

In order to deal with all these numbers and make the measurements that they need, astronomers use special computer programs called image analysis or processing software.

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