Anders Celsius Observed Aurora Borealis in 1735 and 1736 in England

Summary: Anders Celsius observed the aurora borealis in 1735 and 1736 in England during his five-year study tour of Germany, Italy, France and England.

Swedish astronomer Anders Celsius observed the aurora borealis in England, over Cambridge and London, between Sept. 13, 1735, and April 3, 1736, and also published 316 observations of the aurora borealis, made by himself and others, over Sweden between 1716 and 1732; undated portrait of Anders Celsius by Swedish portrait painter Olof Arenius (Dec. 16, 1701-May 5, 1766), in collection of Uppsala University Museum Gustavianum: National Space Centre @spacecentre, via Twitter Nov. 27, 2020

Swedish astronomer Anders Celsius observed the aurora borealis in 1735 and 1736 in England while he was engaged in a five-year (summer 1732 to summer 1737) international study tour of Germany, Italy, France and England.

Anders Celsius (Nov. 27, 1701-April 25, 1744) observed the aurora borealis ("northern dawn") over England between Sept. 13, 1735, and April 3, 1736. He described his observations in a paper, "Observations of the Aurora Borealis Made in England," which was published in the April to June 1736 issue of Philosophical Transactions of the Royal Society of London.

On Sept. 13, 1735, Celsius recorded one sighting of the aurora borealis, which occurred over Woodford, then a town six miles northeast of London and now in East London, in London's Borough of Redbridge. He situated his report's first observation with respect to Ursa Major the Great Bear constellation.

At 11:30 p.m. on Sept. 13, 1735, he viewed a "bright Band" that almost paralleled the horizon. He placed the band's middle under Eta Ursae Majoris (η Ursae Majoris; Eta UMa, η UMa). Formally named Alkaid, Eta Ursae Majoris is the third brightest star in Ursa Major the Great Bear constellation and, as marker of the tip of the handle, the easternmost star in the Big Dipper asterism. Celsius noted almost constant coverage of Gamma Ursae Majoris (γ Ursae Majoris; Gamma UMa, γ UMa), formally named Phecda, and of Delta Ursae Majoris (δ Ursae Majoris; Delta UMa, δ UMa), formally named Megrez, by "another Light" shooting along the constellation (page 241). Phecda and Megrez mark the bowl's lower left and upper left points, respectively, in the Big Dipper asterism.

On Oct. 4, 1735, between 9:22 and 9:44 p.m., Celsius made 10 observations of the aurora borealis from King Street in Bloomsbury, now a district in Central London's West End. He situated the aurora borealis with respect to Ursa Major the Great Bear constellation and Polaris the North Star.

"A Ray or Stream of Light . . . under the Polar Star" (Polaris; α Ursae Minoris, Alpha Ursae Minoris; Alpha UMi, α UMi) appeared "perpendicular to the Horizon" at 9:22 p.m. but disappeared two minutes later, at 9:24:13 p.m.

Less than three minutes later, at 9:27:6 p.m., Celsius noted: "Two perpendicular Rays shot forth five or six Degrees from the North towards the East."

Then, almost one and one-half minutes later, at 9:28:30 p.m., a "whitish Ray" appeared under the Polar Star (Polaris, from Latin stella polaris, "polar star"). Westward movement of the ray occurred one and one-half minutes later, at 9:30 p.m. One minute later, at 9:31 p.m., the ray was positioned under Eta Ursae Majoris (η Ursae Majoris; Eta UMa, η UMa), which represents the easternmost tip of the Big Dipper asterism's handle. Almost one and one-half minutes later, at 9:31:27 p.m., the ray had "entirely disappear'd."

A little over four and one-half minutes later, at 9:36:8 p.m., Celsius noted a ray's perpendicular ascent by the Polar Star and the Great Bear constellation's Polaris-pointing stars, spectroscopic binary star system Alpha Ursae Majoris (α Ursae Majoris; Alpha UMa, α UMa) and Beta Ursae Majoris (β Ursae Majoris; Beta UMa, β UMa). Alpha Ursae Majoris, formally named Dubhe, and Beta Ursae Majoris, formally named Merak, represent the upper right and lower left points, respectively, of the Big Dipper asterism's bowl. Not quite four minutes later, at 9:40 p.m., Celsius observed the ray's seemingly gradual movement under Xi Ursae Majoris (ξ Ursae Majoris; Xi UMa, ξ UMa), formally named Alula Australis. Xi Ursae Majoris, which was discovered to be a binary star system May 2, 1780, by Uranus discoverer Sir William Herschel (Nov. 15, 1738-Aug. 25, 1822), lies in the Great Bear's left hind paw, far to the south of the Big Dipper's two pointer stars.

The absence of rays ended the Swedish astronomer's observing session at 9:44 p.m. He commented, however: "But whether there were any Remains of Light near the Horizon, or in the West, I could not see, upon account of the neighbouring Houses" (pages 241-242).

On Oct. 11, 1735, he made four observations between 10:37 and 10:43 p.m. in London. He situated his sightings with respect to the Great Bear constellation and Polaris the North Star.

At 10:37 p.m., two bright rays streamed under Zeta Ursae Majoris (ζ Ursae Majoris; Zeta UMa, ζ UMa), formally named Mizar, and Epsilon Ursae Majoris (ε Ursae Majoris; Epsilon UMa, ε UMa), formally named Alioth. Quadruple star system Mizar and Ursa Major's brightest star Alioth are the second and third stars, respectively, from the tip of the Big Dipper asterism's handle.

Two minutes later, at 10:39 p.m., a ray appeared between the Epsilon Ursae Majoris and the Polar Star.

One-half minute later, at 10:39 1/2 p.m., a pyramidally shaped ray appeared above Eta Ursae Majoris (η Ursae Majoris; Eta UMa, η UMa), the star marking the tip of the Big Dipper asterism's handle. Celsius noted "not any Motion parallel to the Horizon; but they entirely disappear'd" at 10:43 p.m. (page 242).

On Jan. 11 and Jan. 12, 1736, Celsius made 10 observations of the aurora borealis between 10 p.m. Jan. 11, and 12:11 a.m. Jan. 12, in London. He located the aurora borealis with respect to the Great Bear constellation and Polaris the North Star.

At 10 p.m. on Jan. 11, 1736, Celsius noted the appearance of an "indifferently bright Arch, pale towards the Edges," at a height of 16 degrees. One of the arch's ends displayed an eastward descent under Eta Ursae Majoris (η Ursae Majoris; Eta UMa, η UMa). He added: "And lucid Streaks appear'd now and then over this Arch."

Almost one and one-quarter hours later, at 11:13 p.m., a "very bright Tract" appeared under, and parallel to, the arch. Located above five degrees above the horizon, this tract contained rays shooting "from West towards the Earth."

Two minutes later, at 11:15 p.m., this lower arch had become "very faint."

Two minutes later, at 11:17 p.m., the first (upper) arch had become brighter, while the second (lower) arch had "almost blended with the upper, and broken in the middle."

Three minutes later, at 11:20 p.m., faint rays beset the "whole Arch."

One minute later, at 11:21 p.m., one of the rays was positioned beneath the Polar Star.

Six minutes later, at 11:27 p.m., Celsius reported: "No Arch, nor Rays, but bright Tracts dispersed here and there."

Nine minutes later, at 11:36 p.m., he noted: "The Light reached up to the Polar Star, and somewhat higher."

Eight minutes later, at 11:44 p.m., a "lucid Ray" appeared beneath the Polar Star.

The session's 10th and last notation occurred less than half an hour later, at 11 minutes past midnight. Celsius noted a cloudy, overcast sky broken by "one lucid Streak, which appear'd three or four Degrees to the East of the North" (pages 242-243).

Feb. 16, 1736, found Anders Celsius in the East of England at the University of Cambridge's Clare Hall. He made one observation of the aurora borealis, sited with respect to the Great Bear and Little Bear constellations.

At 8:15 p.m., he noted a brightly shining moon. Two "perpendicular Streams" appeared between constellations Ursa Major and Ursa Minor (page 243).

The Swedish astronomer's last observations of the aurora borealis over England took place April 3, 1736, in London. He referenced the aurora borealis with respect to seven constellations: Boötes the Herdsman, Cancer the Crab, Canis Minor the Lesser Dog, Cassiopeia the Seated Queen, Corona Borealis the Northern Crown, Coma Berenices Berenice's Hair and Leo Minor the Lesser Lion.

Celsius reported two observations for April 3. At 8:46 p.m., "a lucid Arch one Degree broad . . . extended along the Northern Crown, the Cingulum Boötis, the Coma Berenices, the lesser Lion and Cancer, as far as the smaller Dog." Cingulum Boötis (Latin for Boötes's belt) is Epsilon Boötis (ε Boötis; Epsilon Boo, ε Boo), formally named Izar. The triple star system resides in the Herdsman's right hip.

A little over three and one-half minutes later, at 8:49:36 p.m., Celsius noted the simultaneous disappearance of the seven constellations-wide arch and appearance of "another broader and brighter Arch under Cassiopea" at a height or seven or eight degrees (pages 243-244).

Celsius concluded his report on the aurora borealis over England with a statement of certainty concerning the times that he gave for his sessions on Oct. 4, 1735, at Bloomsbury and on April 3, 1736, in London. He expressed the relevance of these correct times to the determination of longitude.

Celsius considered: "In the Observations of October 4th, and in the last, I am certain as to the Time of the Clock: So that if it has happen’d that others have observed the same Phaenomena, the Longitudes of Places may be determined by them with greater Exactness than by the Satellites of Jupiter, which I take to be the principal Use that may be made of these Observations, especially in making Maps of the Northern Countries, where these Lights most frequently occur" (page 244).

The takeaways for Anders Celsius's observations of the aurora borealis in 1735 and 1736 in England are that the 18th-century Swedish astronomer reported six sessions, commencing Sept. 13, 1735, and ending April 3, 1736, in the April to June 1736 issue of Philosophical Transactions of the Royal Society of London; that he made these observations during his five-year international study tour of summer 1732 to summer 1737; that five of the six sessions situated the aurora borealis with respect to Ursa Major the Great Bear constellation; and that Celsius considered that "the principal Use . . . of these Observations" lay in the collation of the accurate timings for the second (Oct. 4, 1735) and last (April 3, 1736) sessions with simultaneous, accurate timings made elsewhere for the determination of "Longitudes of Places . . . with greater Exactness."

The aurora borealis favors northern England and Scotland in the United Kingdom, but sometimes extends visibility to southern England; photograph of aurora borealis over sycamore tree (Platanus spp.) near Hadrian's Wall, northern England, by herdiephoto; March 6, 2016: Gizmodo @Gizmodo, via Twitter March 7, 2016

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Swedish astronomer Anders Celsius observed the aurora borealis in England, over Cambridge and London, between Sept. 13, 1735, and April 3, 1736, and also published 316 observations of the aurora borealis, made by himself and others, over Sweden between 1716 and 1732; undated portrait of Anders Celsius by Swedish portrait painter Olof Arenius (Dec. 16, 1701-May 5, 1766), in collection of Uppsala University Museum Gustavianum: National Space Centre @spacecentre, via Twitter Nov. 27, 2020, @ https://twitter.com/spacecentre/status/1332300641599975426

The aurora borealis favors northern England and Scotland in the United Kingdom, but sometimes extends visibility to southern England; photograph of aurora borealis over sycamore tree (Platanus spp.) near Hadrian's Wall, northern England, by herdiephoto; March 6, 2016: Gizmodo @Gizmodo, via Twitter March 7, 2016, @ https://twitter.com/Gizmodo/status/706792806304628737

For further information:

Abbott, David. The Biographical Dictionary of Scientists: Astronomers. New York NY: Peter Bedrick Books, 1984.

Celsius, Andr. "Observations of the Aurora Borealis Made in England." Philosophical Transactions of the Royal Society of London, vol. 39, no. 441 (for the months of April, May, and June, 1736): 241-244.
Available @ https://www.biodiversitylibrary.org/page/49644239

Celsius, Andreas. CCCXVI. Observationes de lumine Boreali: ab A. MDCCXVI ad A. MDCCXXXII partim a se, partim ab aliis, in Suecia habitas. Norimberg æae: Apud Wolfg. Maur. Endteri Hæaeredes, filiam, Mayeriam, hujusque Filium, 1733.
Available via e-rara @ https://www.e-rara.ch/zut/doi/10.3931/e-rara-2622
Available via Google Books @ https://books.google.com/books?id=iE1NAAAAcAAJ

Chaple, Glenn. "Xi Ursae Majoris: The Binary That Got Away." Astronomy > Magazine > Glenn Chaple's Observing Basics. Feb. 25, 2019.
Available @ https://astronomy.com/magazine/glenn-chaple/2019/02/the-binary--that-got-away

Condliffe, Jamie. "Rare Glimpse of Aurora Borealis Spotted in Southern England Last Night." Gizmodo. March 7, 2016.
Available @ https://gizmodo.com/rare-glimpse-of-aurora-borealis-spotted-in-southern-eng-1763250975?utm_campaign=socialflow_gizmodo_twitter&utm_source=gizmodo_twitter&utm_medium=socialflow

Consolmagno, Guy; and Dan M. Davis. Turn Left at Orion. Fourth edition. Cambridge UK; New York NY: Cambridge University Press, 2011.

Ekman, Martin. The Man Behind "Degrees Celsius": A Pioneer in Investigating the Earth and Its Changes. Åland Islands: Summer Institute for Historical Geophysics, 2016.
Available @ https://www.historicalgeophysics.ax/books/degrees_celsius.pdf

Gizmodo @Gizmodo. "Rare glimpse of Aurora Borealis spotted in southern England last night: http://gizmo.do/EikoT3o." Twitter. March 7, 2016.
Available @ https://twitter.com/Gizmodo/status/706792806304628737

Levy, David H. Skywatching. Revised and updated. San Francisco CA: Fog City Press, 1994.

Marriner, Derdriu. "Anders Celsius Established Uppsala Astronomical Observatory in 1741." Earth and Space News. Wednesday, April 28, 2021.
Available @ https://earth-and-space-news.blogspot.com/2021/04/anders-celsius-established-uppsala.html

Marriner, Derdriu. "Big Dipper's Naked Eye Double Star Mizar and Alcor Are Six Stars." Earth and Space News. Wednesday, May 17, 2017.
Available @ https://earth-and-space-news.blogspot.com/2017/05/big-dippers-naked-eye-double-star-mizar.html

Marriner, Derdriu. "Celsius Crater Parents Five Satellites on Lunar Southeastern Near Side." Earth and Space News. Wednesday, April 21, 2021.
Available @ https://earth-and-space-news.blogspot.com/2021/04/celsius-crater-parents-five-satellites.html

Marriner, Derdriu. "Near Side Crater Celsius Honors Swedish Astronomer Anders Celsius." Earth and Space News. Wednesday, April 14, 2021.
Available @ https://earth-and-space-news.blogspot.com/2021/04/near-side-crater-celsius-honors-swedish.html

Moore, Patrick, Sir. Astronomy Encyclopedia: An A-Z Guide to the Universe. New York NY: Oxford University Press, Inc., 2002.

Moore, Patrick, Sir. Philip’s Atlas of the Universe. Revised edition. London UK: Philip’s, 2005.

National Space Centre @spacecentre. "Born #OnThisDay in 1701 Swedish astronomer Anders Celsius was famous for the temperature scale he developed. Celsius built Sweden's first observatory in 1741. He and his assistant Olof Hiortner discovered that the aurora borealis influences compass needles." Twitter. Nov. 27, 2020.
Available @ https://twitter.com/spacecentre/status/1332300641599975426

Uppsala University Department of Physics and Astronomy. "Anders Celsius 1701-1744." Uppsala University Department of Physics and Astronomy > History.
Available @ https://www.astro.uu.se/history/Celsius_eng.html