The cloud, nicknamed “The Brick” for its visual opacity and rectangular appearance, was previously thought to contain more than 100,000 times the mass of the Sun. And from such a dense clump, new massive stars should form, based on researchers' current understanding of star formation. But this is not true, CNN notes.
"Brick" is largely dormant. And the latest observations made with the James Webb Space Telescope have not revealed any hidden young stars. Webb's new data instead showed that the Brick was made of more than just gas. It's also littered with frozen carbon monoxide—much more than previously expected, according to a study published Monday in the Astrophysical Journal. And deeper into the Brick, more ice forms.
The findings could have major implications for how scientists analyze the region in the future. More carbon monoxide ice inside the brick could revolutionize how we study and measure the dark clouds at the center of the Milky Way.
“We're now closer to understanding what exactly is going on in the Brick and where the mass is,” said University of Florida astronomer Adam Ginsburg, lead author of the study. “But we opened up more questions than we closed with this.”
Among these questions: Why and where does this carbon monoxide turn into ice?
Other mysteries related to this region also remain unanswered: why do we not see the formation of new stars? Is brick really not as dense as scientists once believed? And what are these strange protrusions and filament-like filaments that are visible inside the brick?
“We have a lot more research to do before we can really be sure what's going on,” says Ginsburg. “I would say that we are at the stage of forming hypotheses, not at the stage of drawing conclusions.”
Adam Ginsburg and his fellow researchers, who included graduate students at the University of Florida, first got their hands on this new Webb data in September 2022, CNN reports.
This was the decisive moment. As the most powerful space telescope ever built, Webb could offer never-before-seen insight into the project. But right away, Ginsburg and his team discovered that the data required a lot of work. The Webb telescope is oriented using a map to determine which direction it is pointing based on where it is in relation to known stars.
The problem was that “there are so many stars in the center of the galaxy that it gets confusing,” Ginzburg said. So the researchers had to spend months cleaning the data, orienting it so that it would correctly match existing sky maps.
Then, when they took a closer look at the Brick, they discovered that the images from Webb were coming out the wrong color.
“All the stars came out too blue,” Ginzburg said, prompting the researchers to wonder if there was something wrong with the data.
But it turned out, he said, that the problem lay in their assumptions. Scientists did not expect that there would be so much carbon monoxide in the ice - and this, according to the study, caused the color change.
According to Dr. Natalie Butterfield, an assistant scientist at the National Radio Astronomy Observatory who was not involved in the study, studying the existence of ice could have a broad ripple effect on all types of research into the center of the Milky Way.
Butterfield said her own research, which includes studying supernovae and radiation between star systems, could be forever changed by understanding the existence of this carbon monoxide ice. This could change how scientists estimate the mass of all the clouds at the center of the galaxy.
There are a few strange things about all this carbon monoxide ice. For example, the area is quite warm - about 60 degrees Kelvin (minus 351.67 degrees Fahrenheit), while carbon monoxide typically freezes at 20 Kelvin.
It is possible that the dust inside the brick is much cooler than the gas, causing the carbon monoxide around the dust particles to become solid. Or, Ginsburg said, maybe the water freezes, trapping carbon monoxide inside. The answer matters. All the ice in a region like the Brick could give scientists new insights into our solar system—even our home planet.
For example, the ice and water that exist on Earth were probably brought here by comets. So where in the universe ice exists and how it forms can help researchers understand where these comets come from and how they collected the materials they deposited.
And then a big mystery arises, why star formation does not occur inside the “Brick”.
Scientists already know that new stars are formed from dust clouds and hydrogen molecules, CNN notes. But scientists cannot directly observe the hydrogen molecules inside the Brick—or anywhere else in the Universe—because they are invisible to telescopes.
However, scientists also know that for every molecule of hydrogen there is probably a certain amount of carbon monoxide. And carbon monoxide is visible—so scientists can measure it as a proxy for determining how many hydrogen molecules are in a given area.
Researchers have used this method to measure hydrogen molecules for 50 years, Ginsburg said.
But they always assumed carbon monoxide was a gas, not solid ice, as Webb's data showed. The discovery opens a whole new can of worms, Ginsburg said.
Adam Ginzburg noted that it is extremely important for researchers to understand what state carbon monoxide is in - gaseous or solid - in order to come to the right answers.
Each new knowledge about the Brick and its composition better explains why this opaque cloud does not produce stars, although, according to most, it must be one of the most active stellar nurseries in the galaxy.
“This is really a natural place for new stars,” Ginsburg said. “But we didn’t find that much—just a very, very tiny handful.”
There are several possible answers that Ginsburg and other researchers are eager to explore: Perhaps Brick is more sprawling—less compact—than scientists once thought. Or maybe it's just too young and its star-forming days are still ahead of it.
These are questions that Webb can continue to help researchers answer, Ginsburg and Butterfield said.