Mikko Kaasalainen

Mikko Kaasalainen
Born	1965 (1965)
Died	12 April 2020(2020-04-12) (aged 54–55)
Spouse	Sanna Kaasalainen
Academic background
Alma mater	University of Oxford
Thesis	On The Construction of Invariant Tori and Integrable Hamiltonians (1994)
Doctoral advisor	James Binney
Academic work
Discipline	Mathematics, Astrophysics
Institutions	University of Tampere

Mikko K.J. Kaasalainen (1965 – 12 April 2020) was a Finnish applied mathematician and mathematical physicist. He was professor of mathematics at the department of mathematics at Tampere University of Technology. Kaasalainen mostly worked on inverse problems and their applications especially in astrophysics, as well as on dynamical systems.[1][2]

Education and career

Kaasalainen received an MSc in theoretical physics at the University of Helsinki in 1990, moving shortly afterwards to Merton College, Oxford where he completed his DPhil in theoretical physics in 1994, supervised by James Binney. After a series of post-doctoral and senior positions in Europe, he moved to the University of Helsinki and to his present institute in 2009. He led a research group in the Finnish Centre of Excellence in Inverse Problems Research.

Kaasalainen was awarded the first Pertti Lindfors prize of the Finnish Inverse Problems Society in 2001. The asteroid 16007 Kaasalainen, discovered by ODAS in 1999, was named in his honour.[2] The official naming citation was published by the Minor Planet Center on 7 January 2004 (M.P.C. 50463).[3]

Research

Kaasalainen's research interests mostly focused on mathematical modelling in various fields ranging from remote sensing and space research to planetary and galactic dynamics. Typically, the models and mathematical methods Kaasalainen developed with his colleagues are connected with inverse problems. Two such topics featured prominently in Kaasalainen's research:

• Asteroid lightcurve inversion,[4] i.e., the reconstruction of the shapes and spin states of asteroids from their brightness measurements (lightcurves), based on mathematical results and uniqueness and stability theorems[5][6][7] that have been transformed into modelling algorithms with which a multitude of otherwise unresolvable asteroids can now be mapped.[8][9] This method has also been used in the direct verification of the Yarkovsky–O'Keefe–Radzievskii–Paddack effect in our solar system.[10][11][12][13][14][15][16][17][18][19]
• Analysis of large dynamical systems, where torus construction methods[20][21] in phase space allow a compact representation or approximation of the dynamics of the observed system (such as a galaxy).

References

1. Raumonen, Pasi; Åkerblom, Markku; Pursiainen, Sampsa; Paunonen, Lassi (21 April 2020). "Tampereen yliopiston matematiikan professori Mikko Kaasalainen on kuollut" [Mikko Kaasalainen, professor of mathematics at the University of Tampere, has died]. aamulehti.fi (in Finnish). Retrieved 10 May 2020.
2. "(16007) Kaasalainen". Minor Planet Center. Retrieved 25 February 2019.
3. "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 25 February 2019.
4. M. Kaasalainen et al. (2001): Optimization methods for asteroid lightcurve inversion. II. The complete inverse problem. Icarus 153, 37.
5. M. Kaasalainen et al. (1992): Interpretation of lightcurves of atmosphereless bodies. I. General theory and new inversion schemes. Astronomy and Astrophysics 259, 318.
6. M. Kaasalainen and L. Lamberg (2006): Inverse problems of generalized projection operators. Inverse Problems 22, 749.
7. L. Lamberg and M. Kaasalainen (2001): Numerical solution of the Minkowski problem. J. Comput. Appl. Math. 137, 213.
8. Asteroid model website^[dead link‍]
9. "Minor Planet Observer website". Minorplanetobserver.com. Retrieved 4 January 2012.
10. M. Kaasalainen et al. (2007):Acceleration of the rotation of asteroid 1862 Apollo by radiation torques. Nature 446, 420.
11. W. F. Bottke (2007): Spun in the sun. Nature 446, 382.
12. D. P. Rubincam and S. J. Paddack (2007): As Tiny Worlds Turn. Science 316, 211.
13. Chang, Kenneth (13 March 2007). "New York Times 13 March 2007: Prediction Proved: Light Speeds an Asteroid as it Spins". The New York Times. Retrieved 4 January 2012.
14. Jonathan Fildes (7 March 2007). "7 March 2007: Light puts asteroids into a spin". BBC News. Retrieved 4 January 2012.
15. "National Geographic 7 March 2007: Asteroids Spin Faster due to Solar Power, Studies Show". News.nationalgeographic.com. 28 October 2010. Archived from the original on 11 March 2007. Retrieved 4 January 2012.
16. "New Scientist 10 March 2007: Sun sends bumpy asteroids into a spin". Space.newscientist.com. 10 March 2007. Retrieved 4 January 2012.
17. "Die Welt 8 March 2007: Sonnenstrahlen lassen Asteroiden schneller kullern". Die Welt (in German). 8 March 2007. Retrieved 4 January 2012.
18. "London Science Museum Web Exhibitions: Sun puts asteroids in a spin". Sciencemuseum.org.uk. 8 March 2007. Archived from the original on 25 February 2012. Retrieved 4 January 2012.
19. "Corriere della Sera 8 March 2007: Asteroidi piu pericolosi per la Terra con il motore solare naturale". Corriere della Sera (in Italian). Retrieved 4 January 2012.
20. M. Kaasalainen and J. Binney (1994): Construction of invariant tori and integrable Hamiltonians. Physical Review Letters 73, 2377.
21. M. Kaasalainen (1995): Construction of invariant tori in chaotic regions. Physical Review E 52, 1193.

External links

• Mikko Kaasalainen's homepage at the University of Helsinki
• Asteroid model website at the Charles University in Prague^[permanent dead link‍]
• Finnish Centre of Excellence in Inverse Problems Research