Space dust is beautiful. See for yourself in the video above, which takes you on a voyage through the ghostly wisps of dust strewn across the Milky Way. These images are part of a 鈥� the largest map of its kind, covering three-quarters of the sky.
The map will help us better envision what the Milky Way looks like, says of Harvard University in Cambridge, Massachusetts, who led the mapping effort. While we have plenty of ideas about our home galaxy鈥檚 structure, it鈥檚 hard to know for sure 鈥� we can鈥檛 send a telescope outside the galaxy to take a cosmic selfie.
But by knowing how the dust is distributed, astronomers can more accurately piece together the galaxy鈥檚 structure, how its spiral arms are shaped, whether it has a bar across it or how thick the galaxy鈥檚 disc is.
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Sunset stars
The map can also illuminate the birth of stars. For example, Green says, it reveals distinct bubble shapes surrounding Orion A and Orion B, two clouds that are part of the famous Orion nebula. The bubbles form around existing stars which blow a wind of particles out into space. These shove surrounding gas and dust into a hollow sphere and create a shell of denser material that can then form new stars.
Dust is often a nuisance for astronomers, getting in the way of their observations. So accurate maps are crucial to help observe around it.
To make the map, the astronomers used data on 800 million stars taken with the telescope in Hawaii. Dust gives stars a reddish hue in the same way that particles in Earth鈥檚 atmosphere turn a sunset orange, pink and red. Measuring this reddening effect and the distances to the stars allowed astronomers to map where the dust is.
Above all, the map should be a useful research tool, Green says. But even other astronomers can鈥檛 get over the dazzling pictures. 鈥淭hey鈥檙e really excited just to see an image of the Milky Way,鈥� he says.
Accepted for publication in the Astrophysical Journal:
