Imaging the Universe: A binary image activity

What you’ll learn:

How images can be transmitted with binary numbers

See how images can be transmitted with lasers from space!

Key takeaways:

We have limited options sending the imformation gathered in images from space to Earth, which means we use computers to translate the binary information into a photograph.

We have long desired to save images on paper or a screen instead of just our heads.

A long time ago images were taken on film. To get an image you would expose the film, altering the orientation of crystals with photons of light, and develop the film to see what you had. This worked for many years while taking photos of the world around us or our friends. It doesn’t work well if you want to take images of space. How will you get the film back to Earth to be developed?

Scientists have taken to making a binary image with computers using a series of 0s and 1s.

Why 0s and 1s? Computers store all information in a tiny drive that is a set of tiny magnets. Magnets have a north and south pole, so the tiny magnets in computers can be facing up or down. We assign the orientation of the magnets as 0 or 1. Want to make a black and white image? Two options are perfect, a pixel is either black (1) or white (0).

Want grayscale or colors in your digital binary image?

Each pixel of the image must convey that additional information. Computers do that with a larger group of 0s and 1s. Computers use sets of eight 0s and 1s, known as a byte. Coding the set of 8 digits is a language that we call ASCII. ASCII has color codes as well as alphanumeric codes so you can type the letter ‘e’.

Recreate an image from binary code and then increase the resolution (by decreasing the size of each pixel), to see how that effects image quality in this activity.

Project Ingredients:Binary imaging downloadPencil


(Aka cool facts to look at while you are engaged in the STEM activity)

How does Hubble image? It’s crazy that those beautiful images from Hubble were transmitted down to Earth as a series of 0s and 1s! Hubble, in fact, doesn’t even image in color! Astronomers on Earth have to add colors and patch photos together before those glorious images are released to the public.¬†

Collecting photons. Small chips in cameras and even your phones catch and count photons in what is called a charge coupled device, or a CCD. Some CCDs can measure the color of these photons, like those on your cell phone, but others, like those on Hubble only count photons. How can we assign colors to Hubble’s images if we are only counting photons and not looking at colors? Hubble has a specific set of filters that are put in front of the CCD, allowing only a specific color of light through. Hubble can count the photons with the green filter one, then count with a red filter, then with a blue filter, and so on. Astronomers then take all of this data and use it to assign a color to each pixel (or little tiny photon catching bin).