Gravitation is one of the basic forces of nature affecting everything in the universe. Just as gravitation keeps celestial bodies in their orbits, gravity keeps our feet on the ground. It is no wonder, then, that a genuine enthusiasm for her field of research is evident in the voice of Mirjam Bilker-Koivula, whose field of research at the Finnish Geospatial Research Institute FGI is gravity.
'I find gravity research very interesting! It’s a challenging job that I like to do. That's what motivates me the most in my job.'
Mirjam is the leader of the research group Gravity, a part of the Department of Geodesy and Geodynamics. The research group's field of research is variations of the gravity field in time and space. Mirjam says, that to measure gravity they use a gravimeter, which is a very precise type of scales. They also use simple spring balances, where changes in the gravity field are observed with a weight hanging from the end of a spring.
'Gravity data can be used, for example, to calculate a geoid model. The geoid model is a conversion surface linking, for example, heights measured with GPS to the Finnish height system. Gravity has a direct relationship with heights', she says.
From Delft in the Netherlands to Masala in Kirkkonummi
Mirjam has worked continuously at FGI since the mid-90s. She got to know FGI as early as during her geodesy studies at the Delft University of Technology in the Netherlands, when she came to do a traineeship in Finland, at the research centre then known as the Finnish Geodetic Institute.
During her traineeship, Mirjam got to know her current husband. After graduation, she moved permanently to Finland and soon after, returned to her familiar workplace. To start with, Mirjam worked with photogrammetry and GPS-research, before switching to her favourite subject, gravity.
'At school, mathematics and physics were always my strong subjects, but I was also interested in geography. When you mix these, you get surveying and geodesy. From the beginning, I've been interested specifically in gravity and physical geodesy,' Mirjam says.