How long do astronomers live? This is an ostensibly simple question, but it involves a particular conditional probability. If a baby does not die in childbirth and does not die of various childhood diseases, then once that baby has grown up and reached adulthood, he/she could live a long time. Once a person has become an astronomer, that string of conditionals might almost guarantee that the he/she lives longer than the average person.
Furthermore, over time educated people who end up as scientists and professors might be expected to live longer than miners or steelworkers, whose work one would consider dangerous. Yet, some scientists work with hazardous radioactive substances, such as Marie Curie and radium. If you are a medical researcher and work with HIV or the ebola virus, that would be considered a dangerous job.
More general information on life expectancy can be obtained by clicking here .
There is an interesting article in Time magazine, December 4, 2006 issue, pp. 64-71 that deals with the causes of death in the modern day United States. 2003 was the last year on record. In that year 2.5 million people died in the USA. 685,089 died of heart disease. 556,902 died of cancer. 31,484 were suicides. 17,732 were murdered. 3,676 died in motorcycle accidents. 44,757 died in other motor vehicle accidents. Commercial air travel is actually quite safe. In the previous 10 years an average of 82 people per year died in commercial airline accidents. That includes the 265 that died on September 11, 2001.
I have used my biographical index to Sky and Telescope magazine (click here ) as my database. Using the version of the index as it existed in May of 2008, I found I had over 700 people to work with. But a number should be eliminated from the statistics. Not everyone listed has a birth year and death year. Not everyone is astronomer, such as William Shakespeare and Vincent van Gogh. Neither were Generals Thomas Brisbane or Milan Stefanik. But Geoffrey Chaucer should be retained, because he wrote a treatise on the astrolabe. Finally, what should we do about the astronomers who were executed or died in prison? I think they should not be included in the statistics of how long astronomers live. Giordano Bruno (1548-1600) was burned at the stake by the Roman Inquisition. In the October, 1989, issue of Sky and Telescope magazine Robert McCutcheon narrates the purge of Soviet astronomers in the late 1930's. Some of those imprisoned outlived the Stalinist era, but at least 9 astronomers in the database died in prison or were executed.
As far as I know, only two astronomers have been murdered, i.e. killed by an individual as opposed to a governmental entity. Ulugh Beg (1394-1449) was murdered by an assassin hired by his son. He was killed not because he was an astronomer, but because he was the local prince. Auguste Charlois (1864-1910), was murdered by his ex-brother-in-law. The other man was upset that Charlois had gotten remarried. (Incidentally, Charlois is not in the Sky and Telescope index.) Jacob Herschel, the brother of William Herschel, was murdered, but he was not an astronomer. (See A. Latusseck and M. Hoskin, Journal for the History of Astronomy, vol. 34, no. 2, May 2003, pp. 233-234.)
To my knowledge six astronomers have committed suicide. As in the general statistics for the year 2003 referenced above, it is more likely that an astronomer would have died by suicide than by homicide.
In this first graph we show a histogram of 691 astronomers and related people from the Sky and Telescope index. (Shakespeare, van Gogh, and two generals mentioned above are not part of the 691.) The median life span was 72. The three highest peaks in the distribution occur at age 66, 71, and 77 to 78. The histogram is clearly asymmetric.
This next figure shows the individual values of the age at death for astronomers born in the year 1800 and later. The nine red squares correspond to astronomers who were executed or otherwise died in prison as a result of the Soviet purge of the late 1930's. The solid line at the right edge is significant. Say there is an astronomer who was born in 1920, who lived to be 86, and whose death was noted in Sky and Telescope magazine. He/she could not have been part of the database in 2004, the last year indexed. Given that astronomers have lived to more than 100, the database is more and more incomplete starting with birth year 1903.
There are three astronomers in the database who lived to 100 or 101. They were Charles Greeley Abbot (1872-1973), Goethe Link (1879-1980, who was a physician and amateur astronomer who donated his 36-inch telescope to Indiana University), and Giorgio Abetti (1882-1982). Dorrit Hoffleit died in April, 2007, at the age of 100 and 1 month. She is not in the database yet but should be added. The longest-lived astronomer appears to have been Paul Sollenberger, who died in 1995 at the of 103 and 9 months. His obituary was published in the Bulletin of the American Astronomical Society (see below).
The longest-lived person associated with anything astronomical was Live Larsdatter, who worked for Tycho Brahe on Hven or in Copenhagen. She died in 1698, supposedly at the age of 123. See John Robert Christianson, On Tycho's Island: Tycho Brahe and His Assistants, 1570-1601 , Cambridge Univ. Press, 2000, p. 311-312.
There are only 14 individuals with birth year between 315 B.C. and 1394. Their average lifespan was 71.64 +/- 2.95 years, with a median value of 73. After that we can produce a sensible table of mean values.
In the following table we give the average values of the age at death of the astronomers in the database. We bin according to the year of birth. For the 15th, 16th, and 17th centuries we give the full century averages. Then we use 50 year bin widths. Finally, we use 10 year bin widths from the 1840's through the first two decades of the 20th century. We also used a sliding window, incremented by one year at a time, to determine which 10 year period gives the absolute maximum. The last decade which is reasonably complete is 1901-1910. The numbers in parentheses are the mean errors of the mean.
Period N Mean Median 1401-1500 6 61.83 (4.98) 65 1501-1600 21 64.29 (1.83) 65 1601-1700 35 67.40 (2.77) 70 1701-1750 39 68.69 (2.32) 71 1751-1800 52 66.71 (2.12) 69.5 1801-1850 114 69.44 (1.25) 71 1841-1850 26 70.92 (2.21) 70.5 1851-1860 27 74.74 (2.08) 78 1861-1870 43 75.44 (1.97) 77 1867-1876 46 79.41 (1.54) 80.5 1868-1877 44 80.16 (1.44) 80.5 1869-1878 41 80.63 (1.30) 80 <--------- this is the maximum 1870-1879 48 80.15 (1.32) 80 1871-1880 50 80.04 (1.42) 80 1872-1881 48 80.00 (1.46) 80 1873-1882 55 79.36 (1.39) 79 1881-1890 64 77.94 (1.25) 78 1891-1900 73 74.67 (1.32) 77 1901-1910 63 71.35 (1.55) 71 1911-1920 34 70.65 (1.91) 72 *** 1911-1920 [42 74.59 (2.03) 75 ***] Nine Soviet astronomers who died in the period 1938 to 1941 are not included in the statistics. *** The average for the 34 astronomers in the database with birth years 1911-1920 is biased towards a value that is too low because of incompleteness for astronomers that lived (or will live) to 85-101. The corrected average was calculated using the data in the database for birth year between 1901 and 1920 and life spans of 84 to 101.The figure below shows the data given in the table except for the 1911-1920 bin. The maximum occurred for the 10 year bin 1869-1878, when the mean life expectancy was 80.63. (This is plotted as a red triangle.) The least-squares line is fitted to the blue points. The point for 1901-1910 is entirely consistent with the extrapolation of the fit to the blue points. The astronomers born between 1851 and 1900 lived statistically significantly longer than astronomers in any other time period. The trend is already evident in the graph above of the individual lifespans vs. time. The maximum of life expectancy is quite clear in the graph of the averages shown below.
The reasons for the excess of long lived astronomers from the second half of the 19th century are not entirely clear. An astronomer born in the 1870's was generally too old to serve in World War I. One exception was Karl Schwarzschild (1873-1916). His service on the Russian front likely led to his early death.
Astronomers born at the very end of the 19th century did see military service. Otto Struve (1897-1963) served in the Russian Imperial Army during World War I, then with the White Russians against the Bolsheviks during their civil war. Was his life shortened by his military service as a young man, or by the work habits he adopted as a professional astronomer? Probably a combination of the two.
Because of the inherent incompleteness in the database since 1911 we cannot say if the trend shown by the least-squares line in the graph will definitely show an increasing life expectancy. Still, it is very curious that astronomers born in the second half of the 19th century lived longer than astronomers born at the start of the 20th century.
How do these findings compare to data in another database?
There are 350 astronomers who died in the period 1989-2007 and whose obituaries have been published in the Bulletin of the American Astronomical Society . The list can be accessed by clicking here .
In the graph below we plot the age at death for these 350 astronomers vs. their birth year. Unlike the coresponding graph shown above, we are missing a lot of the younger astronomers. For example, in the bin 1901 to 1910, the BAAS obituaries give an average age of 90.60 +/- 0.63 and a median age of 91. Given the conditional requirement that these astronomers died in 1989-2007, the minimum possible age would be 79. And, in fact, the minimum age of the 57 astronomers in this bin was 80. The mean age is (not surprisingly) much higher than the corresponding value for the 63 astronomers in the Sky and Telescope index who were born 1901-1910. And that excludes four Soviets purged in the 1930's.
For 341 astronomers from the BAAS list born 1901 and later the mean age was 73.86 +/- 0.82, with a median value of 77. For N = 143 astronomers in the Sky and Telescope list born 1901 and later the average age was 66.01 +/- 1.14, with a median value of 66. Neither of these values should be quoted as the life expectancy of astronomers born in the 20th century. To get the proper value of the mean age in any given bin, one must not truncate the low or high end of the distribution. Both databases have truncation problems for 20th century astronomers.
There are only six astronomers in both databases: Jan Oort, Fred Whipple, Clyde Tombaugh, Subrahmanyan Chandrasekhar, John Bahcall, and Janet Mattei. The longest lived astronomer was Paul Sollenberger, who died in 1995 at the age of 103 and 9 months. Theodore Jacobsen (1901-2003) slightly outlived C. G. Abbot and Goethe Link.
Last revised on 21 May 2008.
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