Legendary science communicator, Professor Arthur Bleksley, honoured in memorial lecture

Wits University honoured legendary public scientist, Professor Arthur Bleksley, in a memorial lecture, presented by astronomer Professor David Block, in the Wits Anglo American Digital Dome.

In the lecture, titled The Poetry of Light: JWST and the Dawn After Darkness, Block explored how the James Webb Space Telescope was transforming astronomers’ understanding of the early universe.

Bleksley was a pioneering Wits University professor in applied mathematics. He played a key role in bringing astronomy to the South African public. He helped establish the Johannesburg Planetarium, where he introduced generations of students and visitors to the wonders of the universe. Through public lectures, radio programmes such as Test the Team, and his teaching, Bleksley believed that scientific knowledge should not remain inside universities but should be shared widely.

Wits Vice-Chancellor and Principal Prof Zeblon Vilakazi opened the event by reflecting on Bleksley’s belief that science should belong to society, not only universities.

“Science is not complete until it is shared,” Vilakazi said.

He described the Wits Anglo American Digital Dome as a place that sparked curiosity and imagination for generations of South Africans. Vilakazi recalled visiting the planetarium as a child from Katlehong in the early 1980s.

“I remember coming here as a 12-year-old. It set my gaze and my imagination,” he said. “Before equations, before laboratories, there is wonder.”

Vilakazi warned that science was increasingly challenged by misinformation and said society must defend evidence-based knowledge.

“We must respect experts and invest in laboratories and observatories to unlock the mysteries of the universe,” he said.

Block’s lecture explored how the James Webb Space Telescope was transforming astronomers’ understanding of the early universe.

Launched in 2021, the telescope uses 18 gold-plated mirrors and infrared instruments to detect extremely faint light from distant galaxies.

Block said the telescope allowed scientists to see galaxies that formed soon after the Big Bang, over 13 billion years ago.

“Each photon carries the history of stars, the chemistry of nebulae and the imprint of an expanding universe,” he said.

He described the excitement of observing light that had travelled across space for billions of years before reaching Earth.

“I never thought I would live to see photons from galaxies so close to the dawn of the universe,” Block said.

The lecture also highlighted Block’s long-running research on cosmic dust and how dust clouds shape the formation of stars and galaxies.

Throughout the talk, Block paid tribute to Bleksley’s passion for teaching and for sharing science with the public through radio programmes, public lectures and the Johannesburg Planetarium.

Block said Bleksley believed education should inspire curiosity rather than simply deliver facts.

“The mind is not a vessel to be filled, but a fire to be lit,” he said, quoting the ancient Greek philosopher, Plutarch .

The memorial lecture marked both a celebration of Bleksley’s legacy and a reminder of the role universities play in inspiring the next generation of scientists.