Join us for Open Nights at the South African Astronomical Observatory (SAAO) in Cape Town, held on the second and fourth Saturday of every month. (NOTE: Open Nights for December 2025 are scheduled for all 4 Saturdays of the month)
Each evening begins with an engaging presentation on astronomy or a related field of science, followed by a guided tour of the Observatory’s rich history—including our library, museum, and the historic 120-year-old McClean Telescope.
Weather permitting, guests will have the opportunity to enjoy stargazing through the McClean and additional smaller telescopes.
-
- Gates open at 7:30 PM.
- Free entry for children aged 6 and under.
Please email cptbookings@saao.ac.za or call +27 21 447 0025 if you have any queries regarding bookings.
Speaker: Dr. Jéferson A. S. Fortunato
Abstract and Bio:
Title: Fast Radio Bursts and the Hubble Tension
Abstract: Fast Radio Bursts (FRBs) are extremely short, powerful flashes of radio light coming from distant galaxies. In just a thousandth of a second, they can emit as much energy in radio waves as our Sun does in days. As these signals travel across the cosmos, they pass through the cosmic fog of ionised gas between galaxies and get dispersed. By measuring this effect, we can learn how much matter the burst has crossed and how far it has travelled. In this talk, I will introduce what FRBs are and why they have become one of the most exciting mysteries in astrophysics. I will then show how we can use them as new tools to study the expanding Universe and discuss their potential role in the so-called Hubble tension, the current discrepancy in the measured expansion rate of the Universe.
Bio: Dr. Jéferson A. S. Fortunato is a cosmologist and postdoctoral researcher in the HEPCAT (High Energy Physics, Cosmology & Astrophysics Theory) group at the University of Cape Town, supported by NRF. Originally from Brazil, he works on using Fast Radio Bursts as cosmological probes to study the distribution of matter in the Universe and the cosmic expansion history. His research focuses on combining FRB observations with other distance indicators, such as supernovae, to test fundamental relations in cosmology and explore open questions like the Hubble tension.
