The James Webb Space Telescope has super powers! It can see through gas and dust clouds in far away galaxies. Researchers have been using this telescope to study how these spiral galaxies form and change over time – something no one’s ever done before.
Researchers from the University of Alberta’s Department of Physics have recently released a study about 19 galaxies similar to our own. Even though we’re stuck in our galaxy, the data collected by the James Webb telescope helps us learn more about those other galaxies.
The telescope’s mid-infrared instrument is special because it can go through dust and gas clouds to give us more information about how stars are born in galaxies. It also helps us understand how these galaxies are changing. This kind of light is different from the type we can see with our eyes, and it lets us learn about things that are far away and really cold. This infrared light is really important when trying to figure out the cold universe.
The telescope has already taken data from 15 out of 19 galaxies. To figure out what they are seeing, Rosolowsky and Hamid Hassani (the lead author of this paper) studied the infrared light given off by dust particles at different wavelengths. This helped them to classify their findings, like whether they spotted regular stars, giant star-forming areas, or other galaxies in the background.
Using light from stars, scientists used a certain infrared wavelength to take pictures of galaxies. From these images, they could tell the age of the stars and found that the stars were very young. In fact, these stars had formed a lot quicker than most people thought was possible!
The stars in this region are very young. That means they haven’t been around for a long time and are just starting to create new stars, which is really exciting!
The researchers also learned that the brighter the stars were, the more massive they became. It was even helpful in finding stars with higher masses.
Rosolowsky calls high-mass stars “rock stars” because they live quickly and die young, but these stars have a huge impact on the galaxy. When they are forming, they send out lots of gas and solar wind which can stop star formation in one area while making new stars form in another part of the galaxy.
Rosolowsky explains that this bubbling froth found in galaxies is very important because it helps them to use up their fuel slowly. Hassani adds that how new stars are formed has an influence on how galaxies change over time too.
“When a star is forming, the galaxy it’s in becomes active. Lots of dust, gas and other things are generated from that galaxy which trigger the birth of new stars and this helps to keep the galaxy alive.”
Scientists want to build a collection of pictures for distant galaxies, like our own. That way, they can get a better idea of how these galaxies work. To do this, Rosolowsky and Hassani plan to take lots of pictures from different angles. They’re calling their project a “galaxy atlas”.
Rosolowsky says, “We can collect data, create an atlas and see the differences between each galaxy, as well as any patterns that are common to all galaxies.”
Scientists wrote a paper called “PHANGS–JWST First Results: The 21 µm Compact Source Population”. It was put in the Astrophysical Journal Letters on February 16th, 2023. It talks about how they were able to take a closer look at the tiny stars that were causing light from far off places to be brighter than what they would expect. They compared this with other stars and galaxies around them to see their exact structures, brightness, and more.
The PHANGS collaboration has done 21 research projects about the science of galaxies, and it all got published in a special magazine called The Astrophysical Journal Letters.
