Galactic Map Could Finally Solve the Mystery of 'Interstellar Bands':
-3D Model Reveals Clues About How Stars and Galaxies Form
- Map could help scientists explain origin of diffuse interstellar bands (Dibs)
- These dark lines in space hide in the light, and were discovered in 1922
- The map calculates the distances of the material that causes the Dibs
- This could help astronomers explain exactly what causes dark bands
- Scientists believe cracking the mystery surrounding Dibs could arm them with valuable information on how stars and the Milky Way were created
Scientists have revealed the first ever 3D map of bizarre astronomical phenomenon that has baffled scientists for nearly a century.
The new map could help scientists explain what makes up the material that creates 'diffuse interstellar bands' or Dibs.
These are dark lines in space that hide in the light. Scientists have known they exist since 1922, but they still don't know much about them.
Scientists hope to use the map to explain what makes up the material that creates 'diffuse interstellar bands'. These maps show the amount of light absorbed by the DIB (left) and dust (right). Red shows more absorbed light than blue. Top maps are for northern Galactic hemisphere and bottom for southern Galactic hemisphere
Scientists believe cracking the mystery surrounding Dibs could arm them with valuable information on how stars and galaxies are created.
To create the map, scientists focused on the single Dib 8620, one of over 400 absorption lines, with the goal of narrowing down its source.
'Dib 8620 does not seem special compared to other Dibs,' lead author Janez Kos, of the University of Ljubljana in Slovenia, told Space.com.
But, as a spectral feature often used to measure stellar motion, it is 'the most observed DIB.'
Dibs are absorption lines that appear throughout the electromagnetic spectrum. They are caused by the absorption of light by matter in space.
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DIFFUSE INTERSTELLAR BANDS
'Diffuse interstellar bands' or Dibs are dark lines in space that hide in the light.
A student who photographed the light from distant stars discovered these bands in 1922.
Analysing rainbow-colour bands of starlight that have passed through space gives astronomers important information about the make-up of the space materials that the light has encountered.
But in 1922, the student's photographs yielded some dark lines indicating that some starlight was 'missing'' and that something in the interstellar medium between Earth and the star was absorbing the light.
Since then, scientists have identified more than 400 of these diffuse interstellar bands, but the materials that cause the bands to appear and their precise location have remained a mystery.
Researchers have speculated that the absorption of starlight that creates these dark bands points to the presence of unusually large complex molecules, but proof of this has remained elusive.
The nature of this puzzling material is important to astronomers because it could provide clues about the physical conditions and chemistry of these regions between stars.
Such details serve as critical components in theories as to how stars and galaxies formed.
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Four hundred Dibs have been seen - in ultraviolet, visible and infrared wavelengths - throughout space.
Researchers have speculated that the absorption of starlight that creates these dark bands points to the presence of unusually large complex molecules, but proof of this has remained elusive.
Atoms in molecules give off light when their electrons change from one orbit to another.
When the atoms crowd close to each other, one atom interferes with the spectrum of another.
But as yet, nobody has found which molecules and atoms exactly correspond to the Dibs.
The nature of this puzzling material is important to astronomers because it could provide clues about the physical conditions and chemistry of these regions between stars.
In order to investigate Dib 8620, astronomers used the Radial Velocity Experiment (Rave) survey of stars in the Milky Way.
Rave has the spectra of almost half a million stars across the galaxy, all located in the southern sky.
The large size of the sample allowed mapmakers to determine the distances of the material that causes the Dibs, and how the material is distributed throughout space.
The resulting maps showed the intriguing result that the complex molecules thought to be responsible for the Dibs are distributed differently than another known component of the interstellar medium - the solid particles known as dust.
Future studies can use the techniques outlined in the new paper to assemble other maps that should further solve the mysteries surrounding where Dibs are located, and what materials cause them.
'To figure out what something is, you first have to figure out where it is, and that is what this paper does,' said Professor Rosemary Wyse, who is a professor of physics and astronomy at the Johns Hopkins University in Baltimore.
'Larger surveys will provide more details in the future. This paper has demonstrated how to do that.'
The nature of this puzzling material is important to astronomers because it could provide clues about the physical conditions and chemistry
of these regions between stars. Such details serve as critical components in theories as to how stars (pictured) and galaxies formed