Aurora of November 17, 1882
Encyclopedia
The Aurora of November 17, 1882 was a geomagnetic storm
Geomagnetic storm
A geomagnetic storm is a temporary disturbance of the Earth's magnetosphere caused by a disturbance in the interplanetary medium. A geomagnetic storm is a major component of space weather and provides the input for many other components of space weather...

 and associated aurora
Aurora (astronomy)
An aurora is a natural light display in the sky particularly in the high latitude regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere...

 event, widely reported in the media of the time. It occurred during an extended period of strong geomagnetic activity in solar cycle 12
Solar cycle 12
Solar cycle 12 is the twelfth solar cycle since 1755, when recording of solar sunspot activity began. The solar cycle lasted 11.3 years, beginning in December 1878 and ending in March 1890. The maximum smoothed sunspot number observed during the solar cycle was 74.6, and the minimum was 5...

.

The event is particularly remembered in connection with an unusual phenomenon, named a "auroral beam", which was observed from the Royal Observatory, Greenwich
Royal Observatory, Greenwich
The Royal Observatory, Greenwich , in London, England played a major role in the history of astronomy and navigation, and is best known as the location of the prime meridian...

 by astronomer Edward Walter Maunder
Edward Walter Maunder
Edward Walter Maunder was an English astronomer best remembered for his study of sunspots and the solar magnetic cycle that led to his identification of the period from 1645 to 1715 that is now known as the Maunder Minimum....

.

Magnetic effects

The storm was reported in the New York Times and other newspapers as having an effect on telegraph systems, which were rendered useless in some cases. The Savannah Morning News
Savannah Morning News
The Savannah Morning News is a daily newspaper in Savannah, Georgia. It is published by Morris Communications, Inc. The motto of the paper is "Light of the Coastal Empire and Lowcountry"...

reported that "the switchboard at the Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

 Western Union
Western Union
The Western Union Company is a financial services and communications company based in the United States. Its North American headquarters is in Englewood, Colorado. Up until 2006, Western Union was the best-known U.S...

 office was set on fire several times, and much damage to equipment was done. From Milwaukee, the 'volunteer electric current' was at one time strong enough to light up an electric lamp". Measurements taken in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, where the telegraph also was affected, indicated that a telluric current
Telluric current
A telluric current , or Earth current, is an electric current which moves underground or through the sea. Telluric currents result from both natural causes and human activity, and the discrete currents interact in a complex pattern...

 five times stronger than normal was present.

Polar observations

During the event, bright auroral phenomena were recorded from across the world, including several observations from polar latitudes, thanks to the event occurring during the First International Polar Year
International Polar Year
The International Polar Year is a collaborative, international effort researching the polar regions. Karl Weyprecht, an Austro-Hungarian naval officer, motivated the endeavor, but died before it first occurred in 1882-1883. Fifty years later a second IPY occurred...

. In one case, two members of the ill-fated Greely
Adolphus Greely
Adolphus Washington Greely , was an American Polar explorer, a United States Army officer and a recipient of the Medal of Honor.-Early military career:...

 polar expedition, including the astronomer, Edward Israel
Edward Israel
-Early years:Israel was born in Kalamazoo, Michigan on July 1, 1859. He was the son of Mannes and Tillie Israel, the first Jews to settle in Kalamazoo...

, while observing at Fort Conger
Fort Conger
Fort Conger is a former settlement, military fortification, and scientific research post in Qikiqtaaluk, Nunavut, Canada. It was established in 1881 as an Arctic exploration camp, notable as the site of the first major northern polar region scientific expedition, part of the US government's...

 near the north magnetic pole
North Magnetic Pole
The Earth's North Magnetic Pole is the point on the surface of the Northern Hemisphere at which the Earth's magnetic field points vertically downwards . Though geographically in the north, it is, by the direction of the magnetic field lines, physically the south pole of the Earth's magnetic field...

, instinctively ducked to avoid an aurora described as "as bright as the full moon".

Observations in the United States

The Philadelphia Enquirer of November 18 reported a "brilliance as bright as daylight" at Cheyenne
Cheyenne, Wyoming
Cheyenne is the capital and most populous city of the U.S. state of Wyoming and the county seat of Laramie County. It is the principal city of the Cheyenne, Wyoming, Metropolitan Statistical Area which encompasses all of Laramie County. The population is 59,466 at the 2010 census. Cheyenne is the...

, and a "blood red" sky at St Paul. In a 1917 paper for the National Academy of Sciences
United States National Academy of Sciences
The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...

, the electrical engineer, Elihu Thomson
Elihu Thomson
Elihu Thomson was an American engineer and inventor who was instrumental in the founding of major electrical companies in the United States, the United Kingdom and France.-Early life:...

, described seeing "colored streamers passing upward from all around towards the zenith from north, east, west and south", with "great masses or broad bands to the east and west".

Maunder's "strange celestial visitor"

The most unusual of the auroral phenomena, witnessed from Europe at approximately 6 p.m. on November 17, was later described by Edward Maunder in an article of 1916, A Strange Celestial Visitor, written for the 500th issue of the magazine The Observatory. In the article he described it as a "definite body" with a "Zeppelin
Zeppelin
A Zeppelin is a type of rigid airship pioneered by the German Count Ferdinand von Zeppelin in the early 20th century. It was based on designs he had outlined in 1874 and detailed in 1893. His plans were reviewed by committee in 1894 and patented in the United States on 14 March 1899...

"-like shape and pale green colour, passing from horizon to horizon above the moon.

The phenomenon, which transited the sky in approximately seventy-five seconds, also was witnessed by the amateur scientist and astronomer, John Rand Capron
John Rand Capron
John Rand Capron was an English amateur scientist, astronomer and photographer. Though a solicitor by profession, he became an expert on spectroscopy, particularly in relation to the aurora, and published many articles during his lifetime....

, at Guildown, Surrey
Surrey
Surrey is a county in the South East of England and is one of the Home Counties. The county borders Greater London, Kent, East Sussex, West Sussex, Hampshire and Berkshire. The historic county town is Guildford. Surrey County Council sits at Kingston upon Thames, although this has been part of...

. Capron made a drawing of what he referred to as the "auroral beam"; it subsequently was published along with an article in the Philosophical Magazine
Philosophical Magazine
The Philosophical Magazine is one of the oldest scientific journals published in English. Initiated by Alexander Tilloch in 1798, in 1822 Richard Taylor became joint editor and it has been published continuously by Taylor & Francis ever since; it was the journal of choice for such luminaries as...

. In the article, Capron collected twenty-six separate accounts, of which the majority came from the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

: these included reports of the object's torpedo-shaped appearance and an apparent dark nucleus. Several of Capron's correspondents speculated that the phenomenon might have been a meteor
METEOR
METEOR is a metric for the evaluation of machine translation output. The metric is based on the harmonic mean of unigram precision and recall, with recall weighted higher than precision...

, but Capron (and Maunder, who wrote a note in The Observatory on Capron's study) thought it could have represented a transient illumination of an otherwise invisible auroral arc.

The writer, Charles Hoy Fort, later referred to this incident in his book The Book of the Damned
The Book of the Damned
The Book of the Damned was the first published nonfiction work of the author Charles Fort . Dealing with various types of anomalous phenomena including UFOs, strange falls of both organic and inorganic materials from the sky, odd weather patterns, the possible existence of creatures generally held...

, in which he collected further reports from various articles (including several in the journal Nature) published both at the time and subsequently:

In the London Times, Nov. 20, 1882, the Editor says that he had received a great number of letters upon this phenomenon. He publishes two. One correspondent describes it as "well-defined and shaped like a fish … extraordinary and alarming." The other correspondent writes of it as "a most magnificent luminous mass, shaped somewhat like a torpedo."


Although Fort suggested the event had supernatural overtones, scientific opinion was that the "beam" likely represented an extremely unusual auroral phenomenon.

Maunder commented:

This "torpedo-shaped" beam of light was quite unlike any other celestial object that I have ever seen. The quality of its light, and its occurrence while a great magnetic storm and a bright aurora were in progress, seem to establish its auroral origin. But it differed very widely in appearance from any other aurora that I have ever seen.

Solar phenomena

In a 1904 article, Maunder was to describe the storm as a "very intense and long-continued disturbance", which in total, lasted between November 11 and 26. He pointed out that this synchronised "with the entire passage across the visible disc" of sunspot
Sunspot
Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions. They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature....

group 885 (Greenwich numbering). This group originally had formed on the disc on October 20, passed off at the west limb on October 28, passed again east-west between November 12–25, and returned at the east limb on December 10, before finally disappearing on the disc on December 20.

The association of the November 1882 sunspot, or group of sunspots, with the strong auroral display, the collapse of the telegraph system, and variations in the magnetic readings taken at Greenwich was to prompt Maunder to pursue further research of the link between sunspots and magnetic phenomena.
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