These burnt-out stars are reduced to dwindling orbs of gas made up of electrons and carbon and oxygen ions.
This is the first observation of white dwarf stars turning into crystals.
And there are billions of similar sparkling crystal spheres in the Milky Way alone.
"Previously, we had distances for only a few hundreds of white dwarfs and many of them were in clusters, where they all have the same age", said Pier-Emmanuel Tremblay from the University of Warwick, and the lead author of the study. Therefore, gaining a greater understanding of how crystallization can stave off the cooling process, essentially making the stars appear younger than they really are, would help astronomers improve the accuracy of the white dwarf dating technique.
Scientists had predicted five decades ago that as white dwarf stars cool down, they would solidify, or crystallise, but no one knew how much heat would be released in this process or even whether solidification could be proved or observed.
"Before Gaia we had 100-200 white dwarfs with precise distances and luminosities - and now we have 200,000", Tremblay said, giving the satellite the bulk of the credit for the research team's discovery.
The sun will turn into a "crystal ball" - in 10 billion years' time when it dies, scientists have found.
Tremblay said their studies suggested that white dwarfs stop their cooling by turning from liquid to almost 99 per cent solid over about 1.5 billion years.
Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma.
They identified a pile-up, an excess in the number of stars at specific colors and luminosities that do not correspond to any single mass or age.
These white dwarfs were located within 300 light years of Earth.
"We will now have to develop better crystallisation models to get more accurate estimates of the ages of these systems".
You may have heard that billions of years down the road the sun will swell to a ravenous red giant star that will eventually swallow Earth.
Not all white dwarfs crystallize at the same pace.
Just like any other fluid that solidifies in cold enough temperatures, so will those liquified nuclei will when temps in the core cool down enough and releases enough for them to crystallize.
"All white dwarfs will crystallise at some point in their evolution, although more massive white dwarfs go through the process sooner".
And when the process is complete they become what are known as black dwarfs - cold crystal spheres that are not detectable with our telescopes because they don't emit energy.
Scientists further reveal that this crystallisation lasts for several billion years, and the heat released during the process slows down the evolution of the white dwarfs. Our sun is also expected to end its life in the same manner, crystallizing like a jewel in about 10 billion years.