Spiraling filaments feed young galaxies

Galaxies grow by accumulating gas from their surroundings and converting it to stars, but the details of this process have remained murky. New observations, made using the Keck Cosmic Web Imager at the W. M. Keck Observatory in Hawaii, now provide the most direct evidence yet that filaments of cool gas spiral into young galaxies, supplying the fuel for stars.

Artist's impression of a growing galaxy showing gas spiraling in toward the center. Photo: Adam Makarenko/W.M. Keck Observatory

"For the first time, we are seeing filaments of gas directly spiral into a galaxy. It's like a pipeline going straight in," says California Institute of Technology professor of physics Christopher Martin, who is lead author of a new paper. "This pipeline of gas sustains star formation, explaining how galaxies can make stars on very fast timescales."

For years, astronomers have debated exactly how gas makes its way to the center of galaxies. Does it heat up dramatically as it collides with the surrounding hot gas? Or does it stream in along thin dense filaments, remaining relatively cold?

"Modern theory suggests that the answer is probably a mix of both but proving the existence of these cold streams of gas had remained a major challenge until now," says co-author Donal O'Sullivan, a doctoral student in Martin's group who built part of the imager.

"We now have direct evidence that the cold accretion model is a viable explanation for rapid star formation in distant galaxies," says Matthew Benacquista, a program director in the National Science Foundation (National Science Foundation’s Division of Astronomical Sciences.)

YOU MAY ALSO LIKE

NASA Research Gives New Insights into How the Moon Got 'Inked'

A powerful combination of observations and computer simulations is giving new clues to how the moon got its mysterious "tattoos" -- swirling patterns of light and dark found at over a hundred locations across the lunar surface.

Hubble Uncovers Never-Before-Seen Features Around a Neutron Star

An unusual infrared light emission from a nearby neutron star detected by NASA’s Hubble Space Telescope could indicate new features never before seen.

NASA Confirms Evidence That Liquid Water Flows on Today's Mars

New findings from NASA's Mars Reconnaissance Orbiter provide the strongest evidence yet that liquid water flows intermittently on present-day Mars.

Fresh Results from NASA’s Galileo Spacecraft 20 Years On

Far across the solar system, from where Earth appears merely as a pale blue dot, NASA’s Galileo spacecraft spent eight years orbiting Jupiter. The mission ended in 2003, but newly resurrected data from Galileo’s first flyby of Ganymede is yielding new insights about the moon’s environment — which is unlike any other in the solar system.

New Gravity Map Suggests Mars Has a Porous Crust

NASA scientists have found evidence that Mars’ crust is not as dense as previously thought, a clue that could help researchers better understand the Red Planet’s interior structure and evolution.

Jupiter's Auroras Present a Powerful Mystery

Scientists on NASA's Juno mission have observed massive amounts of energy swirling over Jupiter's polar regions that contribute to the giant planet's powerful auroras - only not in ways the researchers expected.