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Jacqueline Antwi-Danso …NSERC Banting Postdoctoral Fellow at the David A. Dunlap Department for Astronomy & Astrophysics

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• Jacqueline Antwi-Danso
• Jacqueline Antwi-Danso

 In the 1990s, astronomers discovered two distant, mas­sive galaxies that had com­pletely stopped, or quenched their star formation. The discovery marked a complete shift in everything astrono­mers thought they knew about how galaxies formed.

Massive galaxies like the Milky Way took several billion years to form. But those new­ly discovered galaxies did so in just a fraction of that time.

“The discovery meant that these galaxies were older than the age of the universe, which is physically impossible,” says Jacqueline Antwi-Danso, the NSERC Banting Postdoc­toral Fellow at the David A. Dunlap Department for Astron­omy & Astrophysics.

Ms Antwi-Danso
Ms Antwi-Danso

“When we look at the formation histories of these distant quenched galaxies, the observations suggest that they formed too quickly and too early compared to what we see in cosmological simula­tions.”

Antwi-Danso is tackling one of astronomy’s biggest chal­lenges in her search to find the earliest distant quenched galaxies in the universe. She is particularly interested in how these galaxies formed and when they stopped forming stars.

Astronomers have discov­ered several more distant, quenched galaxies at increas­ingly earlier periods in the universe’s history. These gal­axies are more massive than the Milky Way and yet formed within a billion years of the Big Bang (which happened nearly 14 billion years ago). In other words, they formed their stars extremely rapidly, unlike any galaxy observed in the present-day.

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So, what does this all mean for astronomers? The extreme star formation processes implied by these observations of distant quenched galaxies are uncomfortably close to the limits permitted by galaxy formation physics. Therefore, trying to understand these objects in more detail is a high priority research area for astronomers.

Massive galaxies like the Milky Way have up to a trillion stars and are characterised by luminous, spiral-like arms of active star formation. Meanwhile, distant, quenched galaxies are composed of old stars and look like relics: small orange-red blobs. This is because their light has been “stretched out” to infrared wavelengths due to the ex­pansion of the universe, which also makes them fainter and harder to spot.

At U of T, Antwi-Danso is building on significant findings from a study she participated in as a PhD student at Texas A&M University. Using the 8-metre telescope at the Gemini South Observatory based in Chile, the FENIKS collaboration surveyed large areas of the sky to increase the chances of finding these rare massive galaxies. They designed and installed two new imaging filters on the telescope to push the bound­ary of what was possible with ground-based infrared tele­scopes. The survey led to two critical discoveries.

The first was the identi­fication of two new distant quenched galaxies. The discovery confirmed existing knowledge about the for­mation histories of distant galaxies, “namely, that these galaxies form too early and too quickly based on what theory predicts,” Antwi-Danso explains.

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The study also highlighted that astronomers can reliably use ground-based telescopes to observe distant quenched galaxies as far back as 12.5 billion years into history of the universe. To detect them at earlier times than this, space-based data is required.

Additionally, astronomers are rethinking long-standing models of galaxy formation as they observe distant quenched galaxies with supermassive black holes at their centers emitting energetic radiation.

This is important, Ant­wi-Danso says, because the differing models for light emission from stars and super­massive black holes can affect estimates of the physical properties of these distant galaxies.

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As more questions arise, there is an increasing need to ensure the accuracy of the physical properties of distant quenched galaxies derived from modeling their observa­tions. Fortunately, there have been significant technological advancements to address this need.

Harnessing the power of space-based technology

• Ms Antwi-Danso was reconized as a
Pillar of University Leadership in 2017
• Ms Antwi-Danso was reconized as a Pillar of University Leadership in 2017

The next stages of Ant­wi-Danso’s research involve further exploration of those two distant galaxies she dis­covered from Chile. To do so, she’s leveraging the power of the James Webb Space Tele­scope (JWST).

Distant galaxies are hard to detect because their emit­ted light is shifted to infra­red wavelengths, where the earth’s atmosphere blocks most of the light. The sky in the infrared is about 10,000 times brighter than the typical distant massive galaxy. This makes it extremely difficult to detect the most distant quenched galaxies using ground-based telescopes.

The JWST – which launched in December 2021 – is about 100 times more sensitive than the largest ground-based infrared telescopes and can observe galaxies in a fraction of the time of its predeces­sors.

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In fact, it has doubled the number of spectroscopic ob­servations of the most distant, quenched galaxies within only two years of operation. Before its launch, astronomers had spectra of only 35 of these galaxies observed within the first two billion years of the universe’s history.

To further observe those two galaxies, Antwi-Danso will use data from the JWST to ex­amine their spectra – the light emitted by these galaxies over a range of wavelengths – which can reveal information like chemical composition. Insights will help provide a more accurate understanding of their formation histories to compare with updated cosmology simulations, and, hopefully, offer new an­swers about possible tensions between theory and observa­tions.

Additionally, Antwi-Danso is part of the Canadian NIRISS Unbiased Cluster Survey (CA­NUCS), a multi-institutional collaboration that uses gravi­tational lensing — a phenom­enon where a massive object acts as a cosmic magnifying glass — to study the building blocks of the earliest galaxies.

Within that collaboration, Antwi-Danso is also a re­searcher on the Technicolor Survey, which employs mul­tiple filters on the JWST’s Near-Infrared Camera to observe quenched galaxies at wavelengths that are inacces­sible from the ground.

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“We want to find galaxies that contain the first gen­erations of stars, and then model their observations with galaxy formation models to infer their physical properties and star formation histories,” Antwi-Danso says.

With the technological advantages provided by the JWST to push the boundaries of distant galaxy observations, Antwi-Danso’s research will provide valuable insight into understanding how early gal­axies came to be.

“We’re really excited to see where the results lead and to compare those observa­tions with current theoretical predictions for these distant massive galaxies.”

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 Dr Penelope Adinku: First Ghanaian female heart surgeon

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Dr Penelope Adiku 1

For Dr Penelope Adinku, becoming Ghana’s first female cardiothoracic surgeon was never part of her childhood plans. As a young girl, she was more interested in books and once dreamed of becoming an author of children’s books.

Reserved, bookish and competitive, she loved reading Enid Blyton, Nancy Drew, the Hardy Boys, The Famous Five and The Babysitters Club. She also enjoyed dancing, while church gradually became an important part of her life.

Dr Adinku

Medicine became an option through her family. Her father, Mr Ambrose Tettey, is a pharmacist and her mother is a teacher. Her immediate older sister entered medical school before her, and watching her journey, together with the encouragement of her parents, eventually influenced Dr Adinku to pursue medicine.

Her earliest memories of hospitals were, interestingly, linked to recovery. Whenever she was admitted as a child, her parents knew she was improving when she would tell her father, “Daddy, I can spell…”

She eventually discovered her passion for surgery during her final year of medical school. While rotating through the Department of Surgery, she watched surgeons treat patients and realised that she wanted to become one.

Dr Adinku

Her interest in cardiothoracic surgery grew during her housemanship in paediatrics, where she encountered children with congenital heart disease. She developed a desire to help such children, drawing her towards the highly specialised field.

The decision was not without resistance. Some health professionals discouraged her because of the demanding nature of cardiothoracic surgery. Her family, however, encouraged her to continue. “They had more faith in me than I had in myself at the time,” she recalls.

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Dr Penelope operating on a patient

What attracted her most was the challenge and the opportunity to intervene when vital organs such as the heart and lungs are compromised. For her, it was the privilege of using her God-given ability to give someone a chance at a healthier and longer life.

Her journey was shaped by navigating a specialty that has traditionally been male-dominated.  She learnt to focus on her work, build trust and let her results speak for themselves.

During her clinical fellowship in Egypt, encouraging consultants gave her opportunities to participate in major cases. The experience strengthened her confidence and helped her realise that she could thrive in the specialty.

She successfully completed her Fellowship training with the West African College of Surgeons and was adjudged the best candidate in Cardiothoracic Surgery at the 2022 Fellowship Examinations, becoming the first Ghanaian female cardiothoracic surgeon.

For Dr Adinku, the achievement is more than a title. She hopes her story will inspire young Ghanaian girls and women to pursue careers that may appear unconventional.

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“If a young girl sees my story and thinks she can pursue her own dream too,’ then that is deeply meaningful to me,” she says.

Her work extends beyond surgery. She is involved in research, medical education, mentorship and professional leadership. She is a member of the Ghanaian Society of Cardiovascular and Thoracic Surgeons and serves as its Treasurer.

Her achievements have earned her the IAP Young Physician Leader Award, the Young Star Award and the Valerie Rusch Mentored Career Development Award from the American Association for Thoracic Surgery.

For her, standing before a patient whose life depends on surgery brings a profound sense of responsibility. She remains focused and humble, recognising that behind every patient is a family hoping for a safe outcome. Her faith helps her trust God with what remains beyond her control.

When an operation does not have the desired outcome, she acknowledges the disappointment, reflects on what happened and discusses difficult cases with senior colleagues and her team. She then moves forward, committed to giving the next patient the same level of care.

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Balancing such a demanding career with family life has not always been easy. Dr Adinku credits her supportive family and friends for helping her through the journey. Outside the hospital, she makes time for family, faith, church and activities that keep her grounded.

She is particularly grateful to her husband, Rev. Ernest Adinku; her parents, Mr and Mrs Ambrose Tettey; her sisters Gertrude, Grace-Imelda and Audrey-Jacqueline and their families; her mentors, close friends, the Wesley Girls High School Sisterhood, past and present directors of the National Cardiothoracic Centre, and colleagues who have supported her.

Dr Penelope and husband Rev Ernest Adinku

She urged young girls to believe in themselves, work hard, learn, ask questions and keep improving.

“There will be people who doubt you, and there may also be times when you doubt yourself,” she says. “Don’t disqualify yourself before you have even had the chance to try. You may be capable of far more than you currently believe.”

By Esinam Jemima Kuatsinu

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Elizabeth Sackey @50: Inspiring journey from Secretarial desk to world of wines, Kente

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Mrs Sackey

Life does not always hand you a script, but you always control how you write the next chapter.

That is the story of Mrs Elizabeth Sackey, affectionately called Liz Sackey, a woman who refused to be put in a box, trading her secretarial desk for the vibrant worlds of global wine and traditional Kente.

Her journey proves that whenever life pushes you, you can use that momentum to leap into greatness.

Born on Friday, June 11, 1976, in New Achimota, Elizabeth inherited a perfect mix of corporate strategy and perseverance.

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Her father, Benjamin Ayivor, was a Marketing Officer for Ghana Airways, while her mother, Janet Ayivor, was an enterprising businesswoman. This combination of global vision and local trade ran deep in her DNA.

Her journey began at Greenhill International School, and later to Mfantsiman Girls Secondary School, Saltpond where she completed her secondary school education.

Soon after, she built her professional foundation at Dard Secretariat School in Accra New Town.

For three years, Elizabeth kept things running smoothly at a fast-paced law firm. Around this time, she also got married to Chief Eng. Daniel Nii Ayi Sackey, Head of Marine Engineering, Ghana Ports and Harbours Authority, with whom she has a daughter.

But Elizabeth wanted more out of life. Balancing a busy life, she went back to school which then pushed her forward into Regent University, graduating with a degree in Banking and Finance in 2009.

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After her National Service in the accounts office of the Volta River Authority (VRA), she and her husband took off to travel overseas many times.

Travel changes you, and for Elizabeth, it sparked a business empire. While exploring global cities, she fell in love with how international shops organised their wines by country of origin.

When she one day stepped off the plane back in Ghana, she did not look for another desk job. Instead, she took a leap of faith and launched Wines of the World Enterprise, bringing that experience straight to Accra.

Entrepreneur by day, scholar by night. She balanced the hustle of business with rigorous study at the Ghana Institute of Management and Public Administration (GIMPA) to earn her Master’s in Development Management.

Her passion for heritage later pulled her into Ghana’s rich textile industry, where she successfully broke into the world of premium Kente.

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“Thirteen years into my entrepreneurial journey, a simple gift of wine and family-woven Kente sparked a brand-new passion,” she discloses to The Spectator.

What started as casual curiosity grew into a deeply fulfilling venture dedicated to sharing Ghana’s rich cultural heritage with the world.

By sharing iconic, masterfully crafted designs like ‘Ewdenisiedwenisu,’ (a beautiful, and complex mix of many different patterns), Emerepa (a distinct collection of traditional structures), and the regal Obaama cloth, she is driving Ghana’s cultural tourism straight into the global spotlight.

After transforming that single baby gift into a thriving venture, she has taken Ghana’s rich heritage far beyond to local borders.

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“I help people globally to choose the perfect colours for their most sacred occasions, using tradition to boost our national tourism. So far, so good,” she declares with pride.”

By introducing the vibrant art of Kente to international audiences, especially those who had admired the fabric from afar but had never actually worn it, she is proving that culture is Ghana’s greatest global asset.

Mrs Elizabeth Sackey firmly believes that if the nation heavily champions the Kente industry, it will skyrocket Ghana’s cultural tourism to incredible new heights.

“The future of Kente is bright and wide,” she states with absolute conviction. International travellers are no longer just admiring the fabric; they want to wrap themselves in it.

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“Pairing an intricately designed Kente with a bold, plain Kente is the ultimate secret,” she reveals with a smile.

For her, styling clients is not just part of the job, it is a natural gift. The moment a client mentions their colour, her creative instincts take over. She freely guides people to their perfect match, ensuring that every vibrant shade shines beautifully for their special occasion without overwhelming the eye.

“Choosing the Kente is one thing, but finding the right person to sew it is an entirely different battle,” she points out.

For her, ensuring a flawless final look means going the extra mile. She frequently steps in to consult directly with fashion designers, dictating the exact style and required yard to protect the fabric’s integrity. It is a meticulous, hands-on approach born out of necessity.

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Despite the immense fulfillment of her textile venture, her journey has been paved with steep hurdles to surmount.

“When the rains fall, the looms slow down and that is just the beginning of the battle,” she reveals.

She says the rainy season brings severe production delays, making bulk orders of complex designs a test of patience. Worse than the weather, however, is the threat of cultural theft. Shoddy imitators and opportunistic businessmen are stealing sacred Kente patterns like ‘Meba wo abrokyire’ (My child lives abroad) and printing them cheaply onto ordinary cloth.

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Fiercely protective of Ghana’s heritage, she is calling on the government to step in, secure the borders, and legally halt the mass piracy of Ghana’s intellectual property.

Liz Sackey is a proud member of the International Central Gospel Church (ICGC). She enjoys unwinding in the kitchen, cooking to the rhythm of her favourite music.

Turning 50 has only amplified her mission to inspire the next generation, sending a powerful wake-up call to the youth to stop being idle.

“The future is bright so grab the massive opportunities waiting for you and boldly venture into new fields,” she advises.

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By Georgina Quaittoo

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