A new map showing the Milky Way and surrounding galaxies has shown matter in the universe is arranged like a sponge, according to Marshall McCall, a physics and astronomy professor at York University in Toronto, Canada.

"Recent surveys of the more distant universe have revealed that galaxies lie in sheets and filaments with large regions of empty space called voids in between," McCall said in a news release. "The geometry is like that of a sponge. What the new map reveals is that structure akin to that seen on large scales extends down to the smallest."

McCall's latest effort -- to plot out bright galaxies within 35-million light years of us in order to better envision where Earth, amid the Milky Way collection of stars and planets and other phenomena, is located in relation to its galactic neighbors -- has found galaxies are positioned along relatively thin stretches of space surrounded by dark matter.

The study has been published in the Monthly Notices of the Royal Astronomical Society. See a video depiction of Marshall McCall's findings here: https://www.eurekalert.org/multimedia/pub/69916.php?from=262270 

"All bright galaxies within 20 million light years, including us, are organized in a 'Local Sheet' 34-million light years across and only 1.5-million light years thick," he said. "The Milky Way and Andromeda are encircled by twelve large galaxies arranged in a ring about 24-million light years across -- this 'Council of Giants' stands in gravitational judgment of the Local Group by restricting its range of influence."

Though scientists have long known the Milky Way, a conglomeration of about 300 billion stars, planets, gas clouds and dust, and its orbiting companion galaxy Andromeda are the dominant members of a small cluster of galaxies named the Local Group, which is about 3 million light years across, not much has been known about the other galaxies in the immediate vicinity.

But, now McCall explains with a degree of certainty that twelve of the fourteen giant galaxies located in the Local Sheet, including the Milky Way and Andromeda, are "spiral galaxies" with highly flattened disks where stars are forming.

The remaining two galaxies -- positioned on opposite sides of the Council -- are described as "elliptical galaxies," with much of their stellar material formed earlier than the flat disk configurations.

McCall also studied how Council spin: "Thinking of a galaxy as a screw in a piece of wood, the direction of spin can be described as the direction the screw would move (in or out) if it were turned the same way as the galaxy rotates," he said. "Unexpectedly, the spin directions of Council giants are arranged around a small circle on the sky. This unusual alignment might have been set up by gravitational torques imposed by the Milky Way and Andromeda when the universe was smaller."

The boundary defined by the Council also led McCall to determine that, because it appears only a small enhancement in the density of matter was required to produce the Local Group, and considering the "orderly" arrangement of the Local Sheet and Council galaxies, nearby galaxies must have developed within a pre-existing sheet-like foundation.