The Seven Dwarfs: New Galaxies Revealed with the Help of a Robotic Telescope

Astronomers have uncovered seven new dwarf galaxies while probing a nearby spiral galaxy. Using a new type of telescope, the researchers' finds may yield important insights into dark matter and galaxy evolution while at that same time signaling the discovery of a new class of objects in space.

The astronomers actually created the robotic telescope that spotted these galaxies with eight telephoto lenses with special coatings that suppress internally scattered light. This makes the telescope adept at detecting the very diffuse, low surface brightness of galaxies.

"We got an exciting result in our first images," said Allison Merritt, lead author of the new paper detailing the galaxies, in a news release. "It was very exciting. It speaks to the quality of the telescope."

Before now, the seven dwarf galaxies had been overlooked due to their diffuse nature. Yet because the new telescope was designed to detect these types of galaxies, the astronomers were in luck.

"We knew there was a whole set of science questions that could be answered if we could see diffuse objects in the sky," said Pieter van Dokkum, who helped design the robotic telescope. "It's a new domain. We're exploring a region of parameter space that had not been explored before."

Currently, scientists plan to further investigate these dwarf galaxies in order to determine whether they're orbiting around the M101 spiral galaxy, or are located much closer or farther away. By studying these galaxies, the researchers may uncover new information about galaxy formation in general.

"There are predictions from galaxy formation theory about the need for a population of very diffuse, isolated galaxies in the universe," said Merritt. "It may be that these seven galaxies are the tip of the iceberg, and there are thousands of them in the sky that we haven't detected yet."

The findings are published in The Astrophysical Journal Letters.