The James Webb Space Telescope is helping astronomers to peer into nearby galaxies and see the elaborate structures of dust and gas which are created by and necessary for star formation.
The Physics at High Angular resolution in Nearby Galaxies, or PHANGS project, involves using data from different telescopes to look at galaxies that are close to us. By using telescopes such as the Hubble Space Telescope and the Atacama Large Millimeter/submillimeter Array, researchers can collect data in different wavelengths such as the visible light and radio wavelengths.
Now, the James Webb Space Telescope can add its data to the project with its ability to look in the infrared wavelength. Looking in the infrared allows Webb to peer through clouds of dust which would be opaque in the visible light wavelength to see structures such as the gas and dust which surround galaxies.
“The high-resolution imaging needed to study these structures has long evaded astronomers — that is, until Webb came into the picture. Webb’s powerful infrared capabilities can pierce through the dust to connect the missing pieces of the puzzle,” Webb scientists write. “For example, specific wavelengths observable by MIRI (7.7 and 11.3 microns) are sensitive to emission from polycyclic aromatic hydrocarbons, which play a crucial role in the formation of stars and planets. These molecules were detected by Webb in the first observations by the PHANGS program.”
For example, this image of galaxy NGC 1433, taken with Webb’s MIRI instrument, shows the bright glow of young stars in the galaxy’s spiral arms. These stars give off radiation that blows away dust and gas, sculpting it into shapes that then glow in the infrared range in which Webb operates.
This next image shows galaxy NGC 7496, also taken with Webb’s MIRI instrument. This barred spiral galaxy has a busy central region called an active galactic nucleus which is glowing brightly and is flanked by two bright spiral arms. The sculpted shapes of the spiral arms are due to filaments of gas that spread around huge bubbles of gas.
So far Webb has collected data from five nearby galaxies, with more observations of a total of 19 galaxies to come in the future.
The research is published in The Astrophysical Journal Letters.