Blobs Of Intergalactic Hydrogen Gas Observed For The First Time May Hold Secrets To The Universe
A never-before-seen cluster of hydrogen clouds have been discovered in the otherwise dark, starless patch of space between the galaxies Andromeda and Triangulum, according to a study published in the journal Nature.
For years, scientists have known that many apparently empty stretches of the Universe contain swaths of hot, ionized hydrogen; however, as lead author Stephen Wolfe explained in a press release, earlier observations of the area between the neighboring galaxies suggested the presence of colder, neutral hydrogen, though whether or not it had a definitive structure or represented a new type of cosmic feature was unclear.
All of this changed when Wolfe and his team were able to obtain high-resolution images of the region using the National Science Foundation’s Green Bank Telescope (GBT) at the National Radio Astronomy Observatory (NRAO) in Green Bank, W. Va.
Using the images, Wolfe said, they “were able to detect discrete concentrations of neutral hydrogen emerging out of what was thought to be a mainly featureless field of gas.”
The researchers speculate that these blobs of gas, which are about as massive as a dwarf galaxy, condensed out of an undiscovered reservoir of hot, ionized gas perhaps accompanied a band of dark matter.
Furthermore, scientists were able to track the motion of the newly-discovered hydrogen clouds and in so doing found they were traveling at similar velocities to Andromeda and Triangulum, suggesting that they are independent entities and not simply “the far-flung suburbs of either galaxy,” according to NRAO astronomer Felix J. Lockman.
As Lockman further explained, the researchers believe dark matter may provide the “gravitational scaffolding upon which clouds could condense from a surrounding field of hot gas.”
Ultimately, scientists are concerned with the presence of the neutral hydrogen gas for several reasons.
For one, the gas could eventually fall into the neighboring galaxies and fuel future generations of star formation. In addition, there is yet great amounts of unaccounted-for normal matter in the cosmos and scientists believe much of it may be found in intergalactic clouds like those observed by the GBT.
In the end, as D.J. Pisano of West Virginia University explained, the discovery may only represent the tip of the iceberg.
“The region we have studied is only a fraction of the area around [Andromeda] reported to have diffuse hydrogen gas,” he said. “The clouds observed here may be just the tip of a larger population out there waiting to be discovered.”