Scientists discover 14 new transient objects in space while peering into the ‘Christmas tree galaxy cluster’

An international team of scientists, led by Haojing Yan of the University of Missouri, used NASA’s James Webb Space Telescope (JWST) to discover 14 new transient objects during their time-lapse study of the galaxy cluster MACS0416, located approximately 4.3 billion light years from Earth, which they nicknamed the “Christmas Tree Galaxy Cluster”.

“Transients are objects in space, like individual stars, that suddenly appear to brighten by several orders of magnitude and then disappear,” said Yan, an associate professor in the Department of Physics and Astronomy.

“These ephemeral objects appear bright only for a short time, then disappear; it is as if we are looking through a moving magnifying glass. At present, we have this rare chance that nature has given us to have a view Although we can currently only see the brightest stars, if we do this long enough – and frequently enough – we will be able to determine how many bright stars there are and what their masses are. .”

Using JWST’s advanced technological capabilities, Yan and his team, including Mizzou graduate student Bangzheng Sun, confirmed the cause of the galaxy cluster’s “flickering lights” or transients that scientists first observed times years ago using NASA’s Hubble Space Telescope.

“We call MACS0416 the Christmas Tree galaxy cluster, both because it is so colorful and because of the flickering lights we find there,” Yan said. “We can see many transients in some regions of this area due to a phenomenon known as gravitational lensing, which magnifies the galaxies behind this cluster.”

The team discovered the transients by studying four sets of JWST images taken of the galaxy cluster over a period of 126 days, or about four months. Yan is particularly excited about the fact that two of the transients are supernovae (stars at the end of their lives), because the team can use them to study supernova host galaxies.

“The two supernovae and the twelve other extremely enlarged stars are different in nature, but they are all important,” Yan said. “We tracked the change in brightness over time through their light curves, and by looking in detail at how the light changes over time, we will eventually be able to know what type of stars they are. More importantly, we will be able to understand the detailed structure of the magnifying glass and its connection with the distribution of dark matter. This is a completely new view of the universe that has been opened up by JWST.

“JWST’s PEARLS: Transients in the MACS J0416.1-2403 Field” was recently accepted for publication in the Astrophysics Journal. It is currently available on arXiv pre-print server.