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Albert Greve
The IRAM Observatories: It was largely thanks to the early site work done by Albert that two IRAM observatories, the interferometer on the Plateau de Bure in France, and the 30-meter telescope at Pico Veleta in Spain, were built at the places where they are now. In 1973, the possible partners of the future millimeter project, that became IRAM, had proposed to measure the water vapor content on three possible sites. The French group at Meudon was tasked with testing the Plateau de Padrille in the Pyrenees, the British group at the Appleton Laboratory was given the task of testing the site of Montbel in the Massif Central, and the German group at the Max-Planck-Institut für Radioastronomie at Bonn was tasked with testing the site of Plateau de Bure in the Hautes-Alpes, a site that had already been considered by the Meudon group. Albert Greve was in charge of the German group. During 1974, Albert made measurements on the Plateau de Bure with the telescope operators who were then working at the 100-m Effelsberg telescope, near Bonn, all living under difficult conditions in a pre-fabricated container building set up on the Plateau for these tests. His group regularly took weather data, using, among other instruments, infrared hygrometers that Albert himself had developed, in order to measure the amount of precipitable water vapour in the atmosphere. It was in part thanks to these measurements that the Plateau de Bure was finally chosen as the site for the IRAM Interferometer. In 1975, shortly after the tests of Plateau de Bure, Albert was sent to southern Spain, to study another possible site, at Pico Veleta, in the Sierra Nevada, near Granada. This time he used data from balloon instruments deployed each day by the meterological services, as well as his own infrared hygrometers. In parallel, he made the first inquiries into the logistical possibilities for a observatory station headquarters located in Granada. Thus also in this case, it is partly due to the efforts of Albert, 36 years ago, that today we have the IRAM observatory on Pico Veleta. In the 1980s, Albert joined the IRAM staff, and continued his services in making, for each newly-constructed IRAM antenna, the initial theodolite measurements of the surface alignment. He started this work on the 30-m telescope in Spain, and continued this type of measurement on the first five of the six antennas on Plateau de Bure. Thanks to his good knowledge of the observatory in Spain, Albert was named station manager at Granada during the period 1990 through 1992. In this period, and during the following years, he became an expert in the field of the thermal behavior of antenna structures, which is a crucial problem for radio observations at millimeter and sub-mm wavelengths. Thanks to this expertise, Albert was highly in demand to serve as advisor on the design of other millimeter telescopes in the world, and in particular, for the antennas of the Atacama Large Millimeter Array (ALMA), that started its first astronomical observations at the Chajnantor Plateau in Chile in 2009. Scientifically, Albert was initially trained as an optical astronomer, and during his career, he observed at many optical telescopes in the world, taking spectra of nearby galaxies. Albert published over 175 scientific papers in his career, the most recent published just one month before his passing, in addition to his world-renouned work on the characterization of radio telescope systems. With the IRAM radio telescopes, Albert made an important contribution as local organizer of Very Long Baseline Interferometry (VLBI) observations. After his retirement in 2003, Albert continued working as a consultant for the European Southern Observatory (ESO) for the ALMA project, and continued to write astronomical papers. He even wrote a book, with Michael Bremer, Thermal Design and Thermal Behaviour of Radio Telescopes and Their Enclosures, which is a fundamental reference for the construction of high-precision radio telescopes. Albert was also well-known for his wit. There are many stories that one can tell which describe Albert's wonderful sense of humor. A good example occurred in 1993 when the author first met Albert while we were both working on the construction of the Submillimeter Telescope (SMT) in Arizona. Albert's expertise in antenna surface measurement was being utilized to set the surface of the SMT. The SMT is located on Mount Graham in southwest Arizona about two hours away from the city of Tucson, where the management offices of this facility are located. During one of these two hour drives from Tucson to Mount Graham the author was telling Albert how excited I was to be traveling to Germany in the coming month, as I had not traveled outside of the US before. I was going to fly into Frankfurt, and I told Albert that I really hoped that I would hear someone say "Ich bin ein Frankfurter" (which, as you know, translates literally into "I am a hotdog" in English). Without even a moment's hesitation Albert responded "Ich bin ein Hamburger!" (after which he explained that he grew-up near Hamburg). I think that we both laughed for a good 5 minutes after that. Albert died on 13 June 2011. He was a great scientist, and an even better person. He will be missed by everyone who had the fortune of knowing him.
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