Astronomers have used NASA’s James Webb Space Telescope to observe a rare gravitational lens configuration in a galaxy cluster known as MACS-J0417.5-1154. This configuration has created a cosmic question mark shape, which is the result of a unique alignment between distant galaxies, the lens, and the observer. The red galaxy that forms the question mark shape was only visible with Webb due to its ability to detect longer wavelengths of infrared light that can pass through cosmic dust. The gravitational lensing effect of the galaxy cluster acts as a magnifying glass, allowing astronomers to see enhanced detail in more distant galaxies behind it.
The red galaxy revealed by Webb is interacting with a spiral galaxy that was previously detected by the Hubble Space Telescope. Both galaxies are being magnified and distorted in an unusual way, resulting in five images of the galaxy pair that trace the top of the question mark shape. The researchers have identified this alignment as a hyperbolic umbilic gravitational lens, a rare occurrence in the observable universe. The study not only demonstrates the capabilities of Webb’s Near-Infrared Imager and Slitless Spectrograph in detecting star formation locations within galaxies billions of light-years away but also presents a visually captivating cosmic phenomena.
The research team, led by astronomers from Saint Mary’s University in Halifax, Nova Scotia, used both Hubble’s ultraviolet and Webb’s infrared data to study star formation processes within the galaxies. They found that both galaxies in the Question Mark Pair show active star formation in several compact regions, likely a result of gas from the two galaxies colliding. The galaxies’ shapes do not appear too disrupted, indicating that they are in the early stages of interacting with each other. The newfound dusty galaxy is located at the same distance as the face-on spiral galaxy, suggesting that they are likely beginning to interact.
The images captured by Webb’s NIRISS instrument provide a glimpse of what the Milky Way galaxy may have looked like 7 billion years ago, during the peak of star formation in the universe. The researchers note that the galaxies in the Question Mark Pair are similar in mass to what the Milky Way would have been at that time, offering insights into the early evolution of our own galaxy. Understanding when, where, and how star formation occurs within galaxies is crucial to unraveling the history of galaxy evolution across the universe’s timeline. The study’s findings have been published in the Monthly Notices of the Royal Astronomical Society and are part of the Canadian NIRISS Unbiased Cluster Survey (CANUCS).
The discovery of the cosmic question mark shape in the MACS-J0417.5-1154 galaxy cluster highlights the power of the Hubble and Webb space telescopes in unraveling the mysteries of the universe. This rare gravitational lens configuration provides astronomers with a unique opportunity to study the interactions between distant galaxies and the processes of star formation within them. By analyzing the data collected from these advanced telescopes, researchers can gain valuable insights into the cosmic phenomena that shaped our universe billions of years ago. The study serves as a testament to the advanced capabilities of modern astronomy technology and the ongoing quest to understand the complexities of our vast universe.