Ken Tapping, March 3, 2010

Like many other jobs, astronomy is a profession that involves a fair amount of travel. We go to meetings, spend periods of time working with foreign scientists, and visit observatories to make observations. However, as we sits at airports, and experience unexpected delays, jet lag and other things, we sometimes get a bit fed up. However, compared with our colleagues of a couple of centuries ago, we have it made.

In 1760, French astronomer Guillaume Le Gentil left France for the Pacific to observe the transit of Venus across the solar disc. Until recently these events were critical in establishing the dimensions of the Solar System. Transits of Venus are rare; they come in pairs eight years apart, with a wait of more than a century before the next pair. Owing to delays in sailing, the transit – the first of the pair – took place in beautiful weather while he was still at sea, and incapable of making any useful observations. With the tribulations of long-distance travel in those days, and the possibility of not having another trip funded, he decided to stick around and wait eight years for the next event. The weather was cloudy and he saw nothing. Finally, after surviving storms, yellow fever and other hazards, he arrived back in France after eleven years, to find that he was believed dead, and that his relatives were busy dividing up his possessions.

Le Gentil's adventures are not atypical. Other devoted scientists also had a hard time. Jean-Baptiste Le Chappe got an assignment from the Russian Government to observe a transit of Venus from a remote location in Siberia. The ship went aground so he decided to go by land, 6,000 km, part of which was travelled during the Russian winter. He got his observations, and decided to observe the last of the pair, eight years later, which would be visible from the South Seas. He got his results, then a tropical disease, which killed him. His valuable observations did get home though.

William Wales was dispatched from Britain to Hudson's Bay to observe a transit. He arrived with several months to prepare and the opportunity to experience a Canadian winter. The beds froze; the timbers of his cabin contracted with the cold, making bangs like cannon fire. It was hard to sleep. Then spring came, the ice melted, the weather warmed and the mosquitoes arrived. Wales recorded that he preferred the winter. Then there were astronomers who got lost, killed by natives, got caught up in wars, or simply disappeared. Today we don't have much to complain about.

Actually the era of the peripatetic astronomer is coming to a close. Firstly, modern astronomical instruments need to be operated by experienced operators, not visiting astronomers. Moreover the practice being adopted more and more at observatories is to have several different sets of observations ready to go, and make choices on the basis of observing conditions and equipment performance. When your observation is done, you simply get the data over the Internet. If you really want to work at an observatory, the secret is to develop special expertise in astronomical instrumentation or software. See you at the airport!