Lennart Lindegren

Lennart Lindegren
File:Lennart Lindegren.jpg
Born	1950 Sweden
Residence	Lund, Sweden
Fields	Astronomy, Astrometry, Space science
Institutions	Lund Observatory, Lund University
Known for	Astronomy, Space astrometry, Science of Hipparcos and Gaia missions
Website Personal Homepage

Lennart Lindegren is a member of the staff at Lund Observatory, Sweden, where he obtained his PhD in 1980. Space astrometry and its various applications have been his main interests in astronomy ever since 1976, when he was `recruited' to the Hipparcos project by Erik Høg. In 1990 he took over from Erik as leader of the Northern Data Analysis Consortium (NDAC) for the reduction of the Hipparcos data. As one of the early proposers of the Gaia concept, and subsequently as member of the Gaia Science Team, he has contributed to many aspects of this mission, in particular the astrometric instrument design and accuracy analysis, and the development of concepts and algorithms for the data analysis.

Within the Gaia Data Processing and Analysis Consortium (DPAC), Lindegren leads the scientific implementation of the Astrometric Global Iterative Solution, a core element in the astrometric processing of the Gaia data. Since October 2006, he is also project coordinator for the Marie Curie Research Training Network ELSA (European Leadership in Space Astrometry). The aims of this network are to develop the science of space astrometry and train the next generation of researchers in this area.

On 19 May 1999, Lindegren was awarded the ESA's Director of Science Medal for his extraordinary efforts in ESA's scientific missions. At a ceremony in Bern, Switzerland, the first four medals were presented to "stars" of the Hipparcos mission, Catherine Turon and Jean Kovalevsky from France, Lennart Lindegren from Sweden and Erik Høg from Denmark.

In 2009, Lindegren was elected as a member of the Royal Swedish Academy of Sciences.

Testimonials

Eric Høg: "Lennart Lindegren has played a crucial role in the Hipparcos project ever since he entered the scene of space astrometry in September 1976. This is an account of what I saw during Lennart’s first years in astrometry after I met him in 1976 when he was a young student in Lund".

Eric Høg: "A new era of my life began on 1 September 1973 when I returned to Denmark with my family of five, after 15 years in Hamburg. I had obtained a tenure at the Copenhagen University where I was going to work on the construction of automatic control of the meridian circle in Brorfelde. Very soon, however, I heard of a young student at Lund Observatory who worked alone on modernizing the old meridian circle there. I went to Lund and “found” Lennart. A few years later, Andrew Murray, my old colleague and member of the Hipparcos science team, would say: “Erik, the best you have ever done for astronomy was to find Lennart!” and I agreed".

Eric Høg: "Of his numerous papers I will only mention two. He wrote a paper on “Photoelectric astrometry” (Lindegren 1978), a subject I had proposed, where he systematically discussed the performance of methods for precise image location from observations. It remains a classical paper. The second paper to mention is about the rigidity of the celestial coordinate system obtained by the one-dimensional observations in a scanning satellite as TYCHO/Option A/Hipparcos. The question was asked in 1976 as mentioned above, but it took years before we had the answer which was affirmative as given by Høyer et al. (1981). The study was led by Lennart and contains his brilliant mathematical analysis of the simulations, but he modestly left the position as first author to another person".