Dr Endawoke Yizengaw is a senior scientist at The Aerospace Corporation. He's applying space physics to improve the accuracy of GPS, the navigation system behind apps like Google Maps.
In Ethiopian wisdom, there’s a well-known proverb: ‘Dine with a stranger, but save your love for your family.’ With university degrees from four different continents, space scientist Dr Endawoke Yizengaw (PhD in Physics, 2005) has certainly shared many meals with new acquaintances. But had it not been for the profound support of family members early in life, Endawoke’s education journey may have never made it past primary school.
‘I grew up as the youngest of seven children in my family in Amber, a village in north-west Ethiopia. Although my main task as a child was to look after the family’s cattle, I joined the nearby elementary school through the influence of my grandfather. However, my parents envisioned me taking over the family farm and forced me to stop my education at grade four,’ Endawoke says.
Two years later, policemen came to our home with a letter from the principal of my school. It was a warning letter that urged my father to send me back to school or face a legal penalty. It was shocking news for my parents, but for me a miraculous gift.
In time, Endawoke learned that his late elder brother, an elementary school teacher, had used his influence to pave Endawoke’s way back to school. It’s a gesture for which Endawoke is forever grateful – and one that would establish the role of family, and people who are like family, in nurturing Endawoke’s life-long academic success.
24 hours of darkness: space science in Scandinavia
Although he’d always had a strong interest in physics and maths, Endawoke became particularly fascinated ‘by what’s going on above our head’. After listening to a radio interview with an Ethiopian aerospace scientist, he knew space science was the career for him.
‘It motivated me to search for opportunities around the world to study space science. First, I joined Tromsø University in Norway for my Masters, then La Trobe University in Australia for my PhD.’
During his postgraduate studies, Endawoke faced his first major career challenge. To join Tromsø’s space science program, he had to relocate to Svalbard, north of the Arctic Circle. As an area with one of the most severe weather systems on earth, Endawoke knew Svalbard would be extraordinarily different to Ethiopia.
‘Even with special clothes, the weather was really unfamiliar to me. It was 24 hours of darkness and the wind was really strong and harsh. As there was no public transport, I had to walk each day from my room to the university. The round trip was 6km and the average temperature was -37 degrees, sometimes less,’ he says.
There was nobody there to talk to me in my language. But I did it, because I had a goal and I needed to fulfil it.
'It happens that I was the first black person who stayed there for six months. I even received a letter of recognition from the Mayor of Longyearbyen!' he laughs.
Navigating with satellites
After Svalbard, Endawoke headed south to study his PhD in Australia. He chose La Trobe so he could learn under the late Dr Elizabeth Essex-Cohen (1940-2004), an iconic ionosphere physicist who was recognised internationally for her pioneering work on the Global Positioning System (GPS). The system uses signals transmitted by satellites to help pinpoint locations on Earth.
My time at La Trobe was fantastic. The Agora was my favourite place and the people in the physics department were great.
The climate was a little more familiar, too.
‘The weather was just like Ethiopia, which was fantastic. And there was a huge Ethiopian community in Melbourne, so I felt at home.’
That feeling of belonging was strengthened by the deep connections Endawoke made at La Trobe. When Dr Essex-Cohen fell suddenly and gravely ill, Endawoke transferred his supervision to Emeritus Professor Peter Dyson.
‘All the credit for my success needs to go to Professor Dyson. He is more than a mentor to me; he’s also a father-figure and friend. He treated me like a son and helped me grow as a scientist.’
It was at La Trobe that Endawoke was introduced to GPS, an encounter that has shaped his career and specialisation today.
‘GPS is a navigation system made from a constellation of satellites. They orbit at about 20,000km above Earth. The signals they send us must pass through the most dynamic part of our atmosphere – the ionosphere – which can distort the information encrypted in the signals and affect the navigation accuracy,’ Endawoke explains.
While GPS has many applications, its most well-known use is in helping us navigate via mobile phone. It’s by accessing GPS data through apps like Google Maps or Waze that we receive directions to get us where we need to go. However, the data’s not perfect – which is where Endawoke’s science comes in.
When your cell phone signal travels through the ionosphere, it becomes refracted, reflected or disturbed by weather events in the atmosphere. This means you lose some of the information.
When inclement space weather events, like solar flares or severe geomagnetic storms, cause crucial GPS data to be lost, everything from your mobile phone to the SatNav in your car becomes less precise.
To improve this, Endawoke and his team set up GPS receivers on the ground. Using these receivers, they collect satellite data to find out what space weather event is taking place.
‘We then model the data about that weather event and send it back to the satellite. This way, the satellite corrects itself for different atmospheric weather events, and improves the accuracy of your location data,’ Endawoke explains.
So, how come Google Maps sometimes still sends you the wrong way?
‘If you want to drive from Bundoora to the city, especially during a storm, your GPS might take you somewhere else. In that case, you can blame us! We haven’t corrected the ionosphere correctly, and that’s what we’re working on now.’
The valuable space weather data Endawoke collected during his time at La Trobe has had far-reaching impacts for the space science community. Among them were his research findings from GPS receiver data on Australia’s Federation Satellite (FedSat) – a microsatellite launched to commemorate the centenary of Australian Federation – which made the cover of renowned US scientific journals.
Taking space science to the world
Since completing his PhD, Endawoke has held positions at UCLA and Boston College in the US, and most recently at The Aerospace Corporation, a California-based research and development centre for space science and engineering. The project he started in 2007 – deploying small-scale instruments called magnetometers across Africa, to measure geomagnetic field fluctuations – is now supported by major players like NASA and the National Science Foundation. And he’s continued to travel extensively, placing scientific instruments in every corner of the world to ensure today’s GPS data modelling is as precise as it can be.
‘We need to model the ionosphere to improve GPS communications, but we can’t do it globally unless we know what’s going on everywhere.’
‘Right now, I have 15 magnetometers around the world, with many more instruments to deploy. Soon I’ll be deploying one in Kwajalein, and on Christmas Island, too. With collaborators I’ve also deployed ionosonde, radars, Fabry-Pérot instruments and GPS receivers – there are too many to remember!’
In 2018, Endawoke was awarded the American Geophysical Union’s Joanne Simpson Medal for his significant contributions to the Earth and space sciences by an outstanding mid-career scientist. The award recognised not only his scientific excellence, but also his vital role in advancing space science education in developing countries. Around the world, Endawoke has built capacity among young scientists and helped establish space science programs in places where none exist.
Back in 2007, for example, of 54 African countries only South Africa and Nigeria were engaged in space science research. It’s a huge landmass, but there were no instruments there and no space science programs,’ he says.
Endawoke saw an opportunity to combine instrument deployment in the region with outreach programs for young scientists. Coinciding with the UN-sponsored International Heliophysical Year 2007, he and his team travelled to Africa to set up instruments and develop young talent.
‘We trained young professors and postgraduate students. And now, the number of countries doing space research has grown from just two to fourteen. These countries are not only doing research, but they’re also introducing space science into the curriculum of their universities. In Kenya, Ethiopia and Egypt they’ve started producing their own PhD students.’
For Endawoke, the chance to give back by nurturing the next generation of space scientists is what makes his work most fulfilling.
I love what I’m doing right now. Seeing those young scientists that you’ve helped to grow, who are now professors, makes you feel a lot of pride. That’s the big reward.
And despite his truly global career, he’s respectful of remembering where it all began.
‘My project is called AMBER. The acronym stands for ‘African Meridian B-field Education and Research’, but the name has another meaning, too. It’s the name of the small town in Ethiopia where I was born and grew up,’ he says.
Looking back on his achievements, Endawoke is quick to emphasise that his career path is also possible for others with a passion for science. His advice to young scientists starting out is straightforward:
‘Work very hard. If you have the interest and determination, there’s nothing in this world that you can’t do. If it worked for me, I don’t see why it can't for anyone else!’
Last updated: 5th June 2019