Decoding the cosmos: how Dr Lexy Andati’s scientific software makes raw space data make sense

Date Released: Mon, 1 December 2025 15:02 +0200

By Siqhamo Jama

 

In a quiet corner of Nairobi, a young girl once sat before her father’s old computer, determined to figure out how people got inside the television. When she finally managed to play a movie with sound but no picture, she was thrilled. The screen stayed black, but it didn't matter. She had made something work. It was a spark of curiosity that would, years later, carry Dr Lexy Andati across galaxies.

Today, Dr Andati is a postdoctoral fellow at the Rhodes University Centre for Radio Astronomy Techniques and Technologies (RATT), decoding faint radio signals from deep space. Her work with radio telescopes helps scientists understand the invisible magnetic fields that shape galaxies and influence the galaxies’ evolution. “We can’t see magnetic fields directly,” she explains. “But we can see their fingerprints on the light we receive.”

But Dr Andati didn’t start her academic journey in astronomy. “My first degree was in microprocessor technology and instrumentation. I just loved computers,” she recalls. A bursary call from under the NRF- South African Research Chairs Initiative (SARChi) for the Square Kilometre Array (SKA) project, a global effort to build the world’s largest radio telescope, brought her to South Africa. “I applied because it involved programming. I had no prior astronomy knowledge. I just showed up.”

That leap of faith led her into one of the world's most ambitious science projects. The SKA’s South African component, the 64-dish MeerKAT array, sits in the stillness of the Karoo, far from radio interference. Each dish captures ancient radio waves from galaxies millions of light-years away. Processing this immense, constant flow of data requires advanced computational techniques. And it was here, at the intersection of data and discovery, that Dr Andati found her place.

She describes computational science simply as “using computers to help us think faster”. By designing and refining algorithms, she helps translate complex radio data into clear, usable images and models. “Astronomy is full of invisible things,” she says. “We can’t touch or see them, but we can detect their effects. My job is to help make sense of those effects.”

Her growing impact didn’t go unnoticed. Less than a year ago, she was awarded one of the L'Oréal-UNESCO For Women in Science Young Talent prizes for Sub-Saharan Africa.

More recently, Dr Andati was awarded the 2025 Kambule Doctoral Dissertation Award at the Deep Learning Indaba in Kigali, because of her work on implementing software tools that help in the study of magnetic fields of the radio galaxy Pictor A. The project beautifully merged astrophysics and software development, combining the two passions that have guided her since childhood. The recognition, she says, was “deeply validating”.

“It wasn’t an easy journey,” she recalls. “I came from a different academic background and had to switch fields completely at Masters level. I started with so much self-doubt. I never imagined I’d end up winning awards.”

She credits her mentors with helping her navigate the steep learning curve. “I was lucky to have very patient supervisors. They let me learn at my own pace. They nudged me in the right direction but did not spoon-feed me.”

Being a Black woman in physics, she admits, comes with its own challenges. “Often, I’d walk into a room and realise I’m the only woman present. And some of the time, I was also the only Black person. Sometimes it felt like I was carrying my whole country on my back.”

Over time, she has learned to disarm imposter syndrome. “I realised that if I say something wrong, someone will correct me, and we move on. It’s better than staying silent.”

Now, Dr Andati hopes to inspire more young Black women to make their mark. “Radio astronomy is growing in Africa,” she says. “The tools we develop here don’t just serve astronomy. They can be applied wherever there’s big data, from health research to environmental science.”

She smiles. “The most exciting part is knowing that the work we are doing out of Africa contributes to global science. I hope when young girls see that, they will believe it’s possible for them too.”

 

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Source:Communications