Cosmic Distance Ladder
IA supernovae following which, Einstein Cross occured, play a crucial role. And measuring the vast distances of the cosmos poses a significant challenge for astronomers, who employ various methods and tools collectively known as the cosmic distance ladder. These supernovae occur in binary systems where a white dwarf star feeds on matter from its companion, often a red giant until it surpasses the Chandrasekhar limit and collapses due to its mass. These stars shed their outer layers in a massive explosion, temporarily outshining everything else in their surroundings.
In a recent study, an international team of researchers led by Ariel Goobar from the Oskar Klein Centre at Stockholm University made an extraordinary discovery: an uncommon type IA supernova named SN Zwicky (SN 2022qmx).
Unveiling Einstein Ring or Einstein Cross
What made this discovery even more astonishing was the discovery of the Einstein ring, somehow, also reffered as Einstein Cross, a unique phenomenon predicted by Einstein’s general theory of relativity. This phenomenon occurs when the gravitational lensing effect generated by a foreground object enhances the light emitted by a distant object.
The team’s achievement was significant because it involved the observation of two exceedingly rare astronomical events that coincided.
Researchers from the Oskar Klein Centre, the Kavli Institute for Cosmology, the Cahill Center for Astrophysics, the Infrared Processing and Analysis Center (IPAC), the Ecole Polytechnique Fédérale de Lausanne (EPFL), the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), the Centre de Recherche Astrophysique de Lyon, NASA Goddard, the Space Telescope Science Institute (STScI), and multiple universities made up the team. Their research paper describing these findings was recently published in Nature Astronomy.
SN Zwicky and Einstein Ring
Initially, the Zwicky Transient Facility at the Palomar Observatory in California detected the supernova. The facility was named after astronomer Fritz Zwicky, who proposed the possibility of dark matter in the 1930s. Several weeks later, the team employed adaptive optics (AO) at the W.M. Keck Observatory in Hawaii and the Very Large Telescope (VLT) at the Paranal Observatory in Chile to observe SN Zwicky. Goobar and his colleagues hypothesized that they were witnessing a solid lensing effect based on the observed brightness. Further observations and images obtained by the Hubble Space Telescope confirmed this hypothesis, revealing that the multiple-image lensing effect was a result of a galaxy in the foreground that magnified the supernova by 25 times!
Studying Mysteries of Einstein Cross
This fortunate discovery of Einstein Cross opens up numerous opportunities for astronomers, enabling them to study SN Zwicky in greater detail and delve deeper into the mysteries of gravitational lenses. As Goobar expressed in a press release from Stockholm University,
“The discovery of SN Zwicky not only showcases the remarkable capabilities of modern astronomical instruments but also represents a significant step forward in our quest to understand the fundamental forces shaping our Universe.” However, the implications extend beyond these two phenomena. The study of type Ia supernovae led astronomers to the groundbreaking realization that the expansion of the cosmos is accelerating.
Universe’s Acceleration Expanding
This discovery of Einstein Cross earned the 2011 Nobel Prize in Physics, which was divided between Saul Perlmutter (The Supernova Cosmology Project) and jointly awarded to Brian P. Schmidt and Adam G. Reiss (The High-z Supernova Search Team). Consequently, observations of SN Zwicky could contribute to unraveling the mystery behind this accelerated expansion. Joel Johansson, a co-author of the study and a postdoctoral fellow at Stockholm University, highlighted the significance of SN Zwicky’s extreme magnification, stating,
Implications and Insights from SN Zwicky Discovery
“The extreme magnification of SN Zwicky gives us an unprecedented chance to study the properties of distant type IA supernova explosions, which we need when we use them to explore the nature of dark energy.”
Furthermore, the discovery of Einstein Cross could throw light on the cryptic nature of dark matter and provide insights into speculations regarding the Universe’s ultimate fate, such as the Big Crunch, Big Rip, or Heat Death.