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A galaxy is an incredible thing.

The vast cosmic objects are born when huge clouds of dust and gas collapse under the weight of their own gravity. Hundreds of billions of stars flicker on, and eventually planets also condense from rings of dust surrounding many of those stars.

Now, a series of newly-processed photos from the Hubble Space Telescope shows a map of star formation in 50 galaxies located within 60 million light-years of Earth.

Scientists used the Hubble to photograph these galaxies in ultraviolet light, revealing bursts of star formation within them, producing a catalogue that reveals 39 million hot, blue stars and 8,000 star clusters, according to NASA.

"There has never before been a star cluster and a stellar catalog that included observations in ultraviolet light," survey leader Daniela Calzetti said in a NASA statement. The survey is called LEGUS, short for Legacy ExtraGalactic UV Survey.

"Ultraviolet light is a major tracer of the youngest and hottest star populations, which astronomers need to derive the ages of stars and get a complete stellar history," Calzetti said.

The ultraviolet catalogue shows off some truly remarkable visions of the star forming galaxies not all that far away from our own.

A photo of Messier 66, for example, reveals the details of the spiral galaxy's arms standing out in stark relief against Messier 66's glowing center.

But these photos are more than beautiful.

They could also help to answer some serious scientific mysteries surrounding how galaxies themselves form.

"By seeing galaxies in very fine detail — the star clusters — while also showing the connection to the larger structures, we are trying to identify the physical parameters underlying this ordering of stellar populations within galaxies," Calzetti said in the statement.

"Getting the final link between gas and star formation is key for understanding galaxy evolution."

Scientists also hope to use the LEGUS catalogue to help inform research done in the future by the James Webb Space Telescope, the infrared space observatory that will be Hubble's successor when it launches in 2020.

The telescope is expected to help piece together more information about how galaxy clusters evolve in galaxies over time.

"Much of the light we get from the universe comes from stars, and yet we still don't understand many aspects of how stars form," team member Elena Sabbi, said in the statement.

"This is even key to our existence — we know life wouldn't be here if we didn’t have a star around."

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