Wednesday, March 22, 2017

Will The Meteors Storm Again?  19th Century American Women Kept Watch

Brief historical background

At the beginning of the 19th century, no one knew that meteor showers were discrete meteor groups arriving on specific calendar dates and that they came from defined regions of the sky.  A meteor storm in November 1833 provoked an inquiry process that developed a knowledge base about showers.  That display filled the sky with thousands of meteors and fireballs that left persistent trains behind.  Its eyewitnesses could readily see that these ‘November meteors’ shot out of the sky from a small region in the Leo constellation.  Professor Denison Olmstead (1791-1859) perused Yale College’s historical astronomical records and learned that there had been bountiful displays the previous two Novembers.  His curiosity about whether 1837 would also see a return led him to organize a hybrid group of New Haven, Connecticut amateur astronomers along with his Yale College students to stand watch and see what happened in November 1837.  Olmstead reconstituted this ‘Yale meteor squad’ in succeeding Novembers and learned that there were returns of the month’s meteors but in much reduced numbers compared to 1833.

            Fast forward to Olmstead’s successor at Yale, Hubert Anson Newton (1830-1896) who performed a second library search in 1863.  He learned that the November Meteors had been giving storm performances for centuries, on about a 33-year cycle.  Newton predicted that November 1866’s sky watchers would see another storm and that good shows might appear for a few years after as well.  Just as Olmstead had done, Newton asked local, national and overseas astronomers to watch Leo and report their results to him.  Newton posted responding observers’ findings in Yale College’s American Journal of Science and Arts, which in the 1860s was a premiere forum for research in the physical and biological sciences.

The debut of American women

By 1866 there were many more American colleges with professors of mathematics and astronomy, including a few institutions which were dedicated to women’s higher education.  Among these were Mount Holyoke College founded in 1837 and Vassar College in 1865. 

One astronomer who heeded Newton’s alert was Vassar’s Professor Maria Mitchell (1818-1889).  Mitchell’s astronomical reputation was established in 1847 when she discovered the first new comet to be found by an American citizen.  In 1866 and 1868, Professor Mitchell assigned her students to stand watch in the after-midnight hours of November 12 and 13.   These young women saw impressive meteor displays.  Mitchell informed Newton that seven students witnessed 354 meteors during a seven-hour overnight watch on November 12/13, 1866. [1]   Two years later, five of her students were thrilled by a better show.  Between 2:00 and 3:00 a.m. on November 14, 1868 they counted 900 meteors.  By dawn they had tallied 3,766 during a five hour watch!  Professor Mitchell was on hand for the 1868 meteor surge and reported to Newton that light flashes from distant fireballs exploding beyond Vassar’s local horizon brightened the moonless sky more than was usual. [2]

Another 1860s-era Leonid witness was Sarah Robinson Trumbull (1829-1909) whose social celebrity derived from her marriage to James Hammond Trumbull, a scholarly Hartford, Connecticut man who had been elected to multiple state offices.  She would have only been known in history as ‘Mrs. J.H. Trumbull.’ if it were not for an early morning meteor watch on November 14, 1867.  Her report of that watch in 1868’s edition of the American Journal of Sciences has preserved her identity as a citizen scientist as well.  On that morning she monitored the sky from her home’s east-facing window while her 10-year-old daughter Annie watched through a northwestern-facing one.  From 4:00 to 5:00 a.m. the two counted 500 Leonids.  Trumbull also noted that in one instant she had seen five meteors dart out of Leo. [3]

Undoubtedly there were many more women who witnessed Leonid showers in the 1860s, but did not know who, or how, or whether to report the startling sky spectacles they had seen.  One of these was Caroline Fletcher Dole (1817-1914).  Her eyewitness accounts about the 1833 storm and the 1865 and 1866 showers only surfaced because her grandson Robert M. Dole, a prominent amateur meteor observer in the 20th century, mentioned them in a family history.  

Leonid meteors were not the only ones watched

When the November meteors’ numbers waned in the early 1870s, fewer American astronomers monitored Leo. However, 1872 had a surprise spectacle in store; meteoroids (rocky particles) from disintegrated Comet Biela flooded that particular November’s skies with meteors from the constellation Andromeda.  This Andromedid shower did not prove to be an annual one and so, attention to it lapsed after a while.  Fickle November showers inclined meteor observers to pay more attention to an annually bountiful one which was known to occur since the 1830s.  This shower, the ‘August meteors,’ later renamed the Perseid shower was observed by some young Indianans in 1882.   

D. Eckly Hunter (1834-1892), Washington, Indiana’s High School principal brought his children and a family friend out to keep a four-hour Perseid watch on the night of August 10 to 11, 1882.  Hunter’s daughters were Mary and Nora, 13 and 10-years-old respectively.  Twenty-four-year old Frank, Hunter’s son and 22-year old Naomi Sanford completed the party.  Professor Hunter kept a record of the number of meteors the party counted and arranged the data in 10-minute intervals.  At the end of four hours the group had spotted 521 meteors.  Using the era’s terminology, Hunter reported that “270 were conformable to radiants in Perseus or Cassiopeia and 50 were unconformable.  Two hundred radiants were not determined but most of the number were doubtless Perseids.”  Just as today’s meteor observers report, Hunter noted that the Perseids often appeared in clusters with minutes-long lulls in between. [4]

The following year, astronomer Daniel Kirkwood (1814-1895) summarized a report made to him about a brilliant meteor, a ‘fireball’ that was seen by many Indiana villagers on January 3, 1883. One couple, Mary E. (Johnston) Campbell (1836-?) and her husband, John Lyle Campbell (1827-1904) witnessed it from separate locations.  Mary made notes of the circumstances of her own observation which she gave to her husband, a professor of mathematics and astronomy at Wabash College in Crawfordsville. Campbell sent Kirkwood the details of the couple’s independent sightings.  From the Campbells and several other people’s observation notes, Kirkwood determined the fireball’s track over Indiana villages and its altitude and the length of its path through the earth’s atmosphere. [5]

In 1881, Mount Holyoke College was presented with an observatory containing an 8-inch (20-cm) Clark refracting telescope.  At the time, Elizabeth M. Bardwell (1831-1899), was Mt. Holyoke’s professor of mathematics and astronomy and director of the astronomy program. On the evening of November 27, 1885 she witnessed a second Andromedid meteor storm.  She called it “an unusual ‘star shower’” and  reported that “meteors were seen in all parts of the sky, (because the) radiant was near the zenith.”  She estimated the rate of the falling meteors as “two to six per minute.”  Bardwell remained vigilant for more storm activity by holding another watch on the 28th.  On the second watch she saw just a few meteors from the radiant point in Andromeda. [6]

Marking time until the next Leonid storm year

For several years after 1885’s reports about the Andromedid storm there were no meteor accounts in the American astronomical press.  It was as if American shooting star observers had suspended routine watches and were waiting for the next Leonid storm predicted to occur in 1899, 1900 or 1901.  However, the meteor showers of 1866-1868 and storms of 1872 and 1885 had helped increase American interest in astronomy.  The groundswell of interest created an expanded market for new astronomical periodicals.  In 1882 Carleton College’s Professor William Wallace Payne (1837-1928) began a new one, Sidereal Messenger.  After eleven years, he created a successor named Popular Astronomy.  Increasingly, astronomical research and developments began to appear in these two publications.  At the same time, American Journal of Science deemphasized astronomical topics perhaps due to the death of H.A. Newton and the absence of a successor astronomer to influence the journal.

Looking for early signs of the next Leonid storm

It wasn’t until 1895 that the Leonids were mentioned again, this time in Popular Astronomy. [7] They were the subject of a watch by Rose O’Halloran (1843-1930), an indefatigable amateur astronomer who most often monitored the cyclical changes in brightness of variable stars. O’Halloran recalled that she had begun to suspect an early return of the November meteors in 1892 when she noticed, “an unusual number of meteors…observed about the 13th of Nov(ember)…”  So, three years later, on the night of November 13/14, 1895 she decided to keep a “prolonged watch” from 9:30 p.m. to 5 a.m. to check if the Leonids’ hourly rate augured an early return.  It was not until well after midnight that the shower’s radiant was high enough in the sky so she could make a valid estimate of its strength.  When only 18 Leonids appeared between 2:00 and 5:00 a.m., she concluded that the shower was not about to storm imminently.   

O’Halloran followed up her 1895 watch by two more in 1896 and 1897.  The 1896 session revealed a promising moderate increase in Leonids: 44 were seen between 2:00 and 4:30 a.m. on Nov. 14th. [8] In 1897, a brilliant gibbous moon which “glided nearer and nearer each night to the radiant point of the Leonids” impaired an assessment of the shower’s full strength because its fainter meteors were impossible to see.  Nevertheless, O’Halloran estimated that those meteors she could see were about one-quarter the number seen the year before on the same date.  Just as in 1896, this result did not suggest to her that the shower’s meteors were about to storm much before 1899. [9]

In 1898, Mt. Holyoke’s Elisabeth Bardwell returned to meteoric astronomy by watching and sketching Leonid meteors on a map prepared for the purpose and published in Popular Astronomy by Herbert Couper Wilson (1858-1940), the publication’s assistant editor.  Wilson published the maps expressly for academic and amateur astronomers to document the paths November meteors had taken.  When the paths were traced backwards they converged on a mapped sky region that indicated the shower radiant’s location in the sky.  Bardwell’s published map showed 42 meteors and Wilson commented that her results were similar to her male colleagues’.  All of their maps disclosed an unsuspected characteristic of the 1898 shower: the radiant encompassed the entire Leo constellation rather than a smaller defined area which was characteristic of previous returns. [10]

1899: Showtime!

Popular Astronomy’s index of articles for the year 1900 listed 11 astronomers who had submitted observation results for the 1899 Leonids. These men had watched the Leonids from New York, Pennsylvania, Massachusetts, Minnesota, Nebraska, Missouri and Colorado and one observer reported from Lisbon, Portugal.  Stripped of all their observational details, their reports supported and concurred with W.W. Payne’s assessment of the year’s shower, in an article he entitled ‘Failure of the Leonids in 1899.’ [11] Too late, an Irish astronomer had published a warning to colleagues that the planet Jupiter’s gravity had diverted the Leonid meteoroid stream away from a full collision course with earth: compared to 1833’s flood of meteors, the 1899 Leonids would be only a trickle.

Although they did not make a summary judgment like Payne’s in their reports, several female astronomers’ results mirrored their male colleagues’: the 1899 Leonids’ numbers were meager.  Anne Sewell Young (1871-1961), Mt. Holyoke’s new observatory director and an assistant, Ella Cecilia Lester (ca. 1874-?) saw only 21 Leonids during a two-hour vigil on the morning of November 15. [12]

As it turned out, the Leonid meteor rate per hour on the night of November 14/15 was better far to the east, in India.  There Mary Etta Moulton (1865-1933), an American missionary and former astronomy student of Payne and Wilson’s kept a Leonid watch 75 miles southeast of Bombay (now Mumbai).[13]  Moulton watched the sky for almost seven hours beginning at 11:00 p.m. on the 14th until 5:45 a.m. on the 15th.  During the interval from 1:00 a.m. to 5:27 a.m., she saw 84 Leonid meteors, for an hourly rate of 19, almost twice her Massachusetts peers’ rate of 10 Leonids per hour. 

Farther west in Colorado the University of Denver’s Professor Herbert A. Howe’s students fared no better even though their watch was held on the date of the predicted storm, November 16, 1899. Howe (1858-1926) had divided four coeds into two dyads. The first pair, Mary C. Traylor and Grace M. Sater counted five Leonids between 1:00 and 3:00 a.m.  Nearby them the second team, Bertha Brooks and Elise C. Jones, saw 14 between 1:00 and 5:00 a.m. [14]  Clearly none of them witnessed a much hoped-for meteor storm with thousands of shooting stars per hour.  The same story prevailed all around the United States and abroad.

No better on the cusp of the 20th century

Even though 1899’s shower was such a debacle, some astronomers believed it was possible that 1900 or 1901’s could be splendid.  Vassar College astronomy students made a maximum effort to detect a storm if it was to occur in 1900.  Groups of them kept watch from 1:00 to 5:00 a.m. on the mornings of November 14 and 15.  The young women counted 42 Leonids on the 14th and 50 on the 15th for average hourly rates of no more than 13 shower meteors. 1900’s shower had been a dud just like 1899’s. [15]

I will close this historical summary with an account of one other American’s enterprising and intrepid effort to report on 1901’s Leonid shower.  Dorothea Klumpke-Roberts (1861-1942) was born in San Francisco but moved with her family to Paris, France where she earned a Doctor of Science degree for a mathematical study of Saturn’s rings. [16] She became such a renowned scientific contributor in Paris that a local aeronautical club offered her a unique observational platform from which to view the Leonids: the car of their lighter-than-air balloon.  She was given last minute pointers about meteoric observation methods by the Meudon Observatory’s director just before the balloon ascended at midnight on November 15, 1901.  She had been alerted by an astronomer colleague who viewed the Leonids the night before that she was not to expect a great number of Leonids and in fact she only recorded eight Leonids seen between 1:20 and 5:10 a.m. on the 16th.  However the few that appeared were dramatic members of the meteoric species.  She wrote that they “were generally brilliant, showing an undulating, iridescent trail, varying in brightness and changing from blue to green, then to red.”  Because the Leonid activity was so sparse and because the moon was nearly full, she had ample time between meteors to survey the landscape and landmarks 500 meters (1600 feet) below. Toward dawn the aeronaut-pilot began a descent.  Her adventure ended safely on a French meadow when the pilot finally “threw out the anchor with one hand and with the other opened the great valve” allowing gas to escape the balloon.  “We felt a slight jolt as the car touched the Earth,” Klumpke-Roberts reported. [17]

A tradition was inaugurated

The preceding sketches amply illustrate the energy and determination that American women have devoted to meteoric study, in particular to investigating reoccurrences of meteor showers.  They began a tradition in observational astronomy that succeeding generations continued to practice and still do today.                                                      
Copyright 2017 Richard Taibi 


[1] Newton, H.A., American Journal of Science, Series 2, Volume 43, p. 78.
[2] Newton, H.A., American Journal of Science, Series 2, Volume 47, p.118.
[3] Newton, H.A., American Journal of Science, Series 2, Volume 45, p.78
[4] Kirkwood, D., The August Meteors, Sidereal Messenger, Volume 1, 1882, p.141-2.
[5] Kirkwood, D., A Large Meteor, Sidereal Messenger, Volume 2, 1883, pp. 8-11. 
[6] Bardwell, E.M., A Star Shower, Sidereal Messenger, Volume 5, 1885, p. 29.
[7] O’Halloran, R., The Meteors of the 13th of November, Popular Astronomy,
Volume 3, 1895, p. 213.  See her biography earlier in this blog.
[8] O’Halloran, R., The Leonids, Popular Astronomy, Volume 4, 1897, p. 453
[9] O’Halloran, R., The Leonids, Popular Astronomy, Volume 6, 1898, p. 51
[10] Bardwell, E.M., Leonid Meteors Observed at Mt. Holyoke College Observatory, Popular Astronomy, Volume 7, 1899, p. 49-50
[11] Payne, W.W., The Failure of the Leonids in 1899, Popular Astronomy, Volume 8, 1900, p.15
[12] Young, A.S. and Lester, E.C., Observations of Leonids at Mt. Holyoke College, South Hadley, Mass.  Popular Astronomy, Volume 7, 1899, p. 532  
[13] Moulton, M.E., The Leonids in India, Popular Astronomy, Volume 8, 1900, pp. 104-105.
[14] Howe, H.A., Leonids at University Park, Colorado, Popular Astronomy, Volume 8, 1900, pp. 21-24
[15] Editor, Leonids at Vassar College, Popular Astronomy, Volume 8, 1900, p. 566
[16] Bracher, K., Klumpke-Roberts, Dorothea, in Hockey, T., et al., Eds., Biographical Encyclopedia of Astronomy, Volume 1, New York: Springer, 2007, p. 646.
[17] Mrs. Dorothy Klumpke-Roberts Observed the Leonids from a Balloon, Popular Astronomy, Volume 11, 1903, pp. 220-222.

No comments:

Post a Comment