Astronomers have announced a very cool find today. What their observations revealed was Eos, a huge crescent-shaped blob of hydrogen gas, only about 300 light-years from Earth. This extraordinary discovery opens up the possibility of other undetected molecular clouds lurking throughout the galaxy. The discovery, made by Blakesley Burkhart while analyzing data from a spectrograph aboard the Korean Science and Technology Satellite-1, highlights the ongoing exploration of cosmic structures that fuel star and planet formation.
Eos—an ancient Greek goddess of dawn, whose name has become synonymous with dawn itself—stretches across almost 100 light-years. That’s roughly the same length as 40 Earth moons placed end to end! This huge size indeed helps make it one of the largest human-made structures detectable from outer space or in Earth’s night sky. Solar System Eos is a CO-dark cloud, meaning that it contains almost no carbon monoxide. This low content, however, makes it difficult to see in order to detect it using traditional methods.
The Method Behind the Discovery
In fact, the extraordinary find of Eos came not from a new observation, but rather from an intensive analysis of two-decade-old spectrographic data. Burkhart used a spectrograph to study far-ultraviolet light. This tool splits the incoming light into individual wavelengths, allowing for unprecedented observation of the cosmic structure.
… It was incredibly serendipitous,” Burkhart said of her findings. As I was researching this data, I noticed this pattern. It was one of those things that I was like, ‘Huh, what is that. That’s unique.’ “This wonderful surprise that Eos gave us illustrates perfectly why it’s so important to go back and re-analyze older data. It unlocks exciting new opportunities to learn about our galaxy.
Burkhart and her team are hard at work designing a mission concept that would form the basis of a NASA spacecraft. We think they’ve picked the perfect name for it—Eos. This one-mission mission to seek out and learn more about this newly discovered molecular cloud and what it may mean for the cosmos.
The Significance of Eos
This is an extraordinary close-up view of the continuous recycling of matter in the cosmos that Eos affords astronomers. As a dense molecular cloud, it’s an important ingredient in feeding the processes that make new stars—and new planets—form. Its crescent shape resulted from complex interactions with the North Polar Spur. Together, all that gas extends huge distances from the plane of the Milky Way.
“This cloud is literally glowing in the dark,” Burkhart remarked, emphasizing Eos’s unique characteristics and its importance in understanding molecular clouds. The complex interactions that give rise to Eos offer a fascinating view into the ongoing, violent processes at play in our galaxy and beyond.
Even with these strides, a lot of questions about Eos are still pending. There’s still loads of unknowns, Burkhart admitted, emphasizing the ongoing pursuit of discovery that defines the field of astronomy.
Future Exploration and Implications
The discovery of Eos has implications that go well beyond this particular cloud. Given how difficult it was to find, its detection implies a vast population of CO-dark clouds could be lurking throughout the galaxy, waiting to be uncovered. A new generation of researchers are exploring these cosmic structures. Their goal is to learn about the processes of star formation and how matter in our universe forms, evolves, and ultimately “dies”.
Astronomers are already thrilled to have the chance to dig deeper into Eos’s characteristics. They’re hoping to learn whether it will begin to form stars before it breaks apart. The possibility of finding more clouds like Eos would change the way we think about star formation and how galaxies evolve.
