Free Astronomy Magazine November-December 2024

NOVEMBER-DECEMBER 2024 the puzzle of galaxy evolution,” said Matthew Hayes from the Depart- ment of Astronomy at Stockholm University and lead author of the study. “Together with models for how black holes grow, galaxy evolu- tion calculations can now be placed on a more physically motivated foot- ing, with an accurate scheme for how black holes came into existence from collapsing massive stars.” Astronomers are also making obser- T his is a new image of the Hubble Ultra Deep Field. The first deep imaging of the field was done with Hubble in 2004. The same survey field was observed again by Hubble several years later, and was then reimaged in 2023. By comparing Hub- ble Wide Field Camera 3 near-infrared exposures taken in 2009, 2012, and 2023, astronomers found evidence for flickering supermassive black holes in the hearts of early galaxies. One example is seen as a bright object in the inset. Some supermas- sive black holes do not swallow surrounding material constantly, but in fits and bursts, making their brightness flicker. This can be detected by comparing Hubble Ultra Deep Field frames taken at different epochs. The survey found more black holes than predicted. [NASA, ESA, Matthew Hayes (Stockholm University) − Image Processing: Joseph DePasquale (STScI). Ack.: Steven V.W. Beckwith (UC Berkeley), Garth Illingworth (UC Santa Cruz), Richard Ellis (UCL)] vations with NASA’s James Webb Space Telescope to search for galac- tic black holes that formed soon after the big bang, to understand how massive they were and where they were located. !