Daily Image
17-01-2014
The Hendrik C. van de Hulst Auditorium
| Submitter: | Michael Garrett |
| Description: | The new auditorium has been in use for almost a year now but it is only recently that the room was formally named in honour of Prof. Hendrik C. van de Hulst (1918-2000). Henk was a young PhD student of Minnaert's in Utrecht during WWII, and came into contact with the Director of the Leiden Sterrewacht, Prof. Jan Oort, when he submitted a paper to a scientific essay competition. Oort immediately recognised the potential in the young man, and challenged him to investigate whether there might be a spectral line observable in the radio part of the e-m spectrum. Oort realised that such a line could be invaluable in mapping out the structure and dynamics of the Milky Way which was difficult to observe at optical wavelengths due to dust obscuration. van de Hulst returned to Oort with the prediction that conditions in the ISM of our own and other galaxies might be suitable for the detection of the 21cm (1.4 GHz) hyperfine transition of neutral hydrogen (HI), the latter being just the most abundant element in the Universe! The rest, as they say is history - leading to the detection of HI at Kootwijk some 7 years later, and the completion of the construction of the 25-m Dwingeloo telescope in 1956. Henk was also a pioneer of the then emerging discipline of Space Science, and was instrumental in the set up of COSPAR and the establishment of our sister organisation SRON. Even today, HI plays an important role in astrophysical research - indeed perhaps more so than ever before - not only does the study of HI in both emission and absorption form a major scientific case for telescopes such as the SKA (and its pathfinders e.g. WSRT-APERTIF, MeerKAT & ASKAP) but it is currently a major hot topic for LOFAR (and other low frequency radio telescopes) via studies of the Epoch of Reionisation. The photo of Henk presented above is now hanging in the new auditorium. We'd like to think that he would take great interest and indeed not a little pride in the various discoveries that will be presented at colloquia and other events organised in the auditorium over the coming years. |
| Copyright: | ASTRON |
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