Nav: Home

Observations of red aurora over 1770 Kyoto help diagnose extreme magnetic storm

October 03, 2017

Auroras are lightshows that typically occur at high latitudes such as the Arctic and Antarctic; however, they expand equatorward under severe magnetic storms. Past observations of such unusual auroras can therefore allow us to determine the frequency and severity of magnetic storms. The more information that can be gathered about historic intense magnetic storms, the greater the opportunity to mitigate disruption of power grids in a future event.

Historical documents are becoming much more accessible for research as newly discovered records surface from private collections across the world. Researchers centered at Tokyo's National Institute of Japanese Literature (NIJL) and National Institute for Polar Research (NIPR) examined a detailed painting from a Japanese manuscript Seikai ("understanding comets") with associated commentary describes a red aurora occurring over Kyoto on 17 September 1770. Also investigated were detailed descriptions of the event from a newly discovered diary of the Higashi-Hakura family of Kyoto.

"The enthusiasm and dedication of amateur astronomers in the past provides us an exciting opportunity," Kiyomi Iwahashi of NIJL says. "The diary was written by a kokugakusha [scholar of ancient Japanese culture], and provides a sophisticated description of the red aurora, including a description of the position of the aurora relative to the Milky Way."

Using astrometric calculations of the elevations of the Milky Way as it would have been viewed from Kyoto on 17 September 1770, the researchers were able to calculate the geometry of the red aurora and check the results against the details from the Seikai painting and the diary. The success of the description of the aurora according to the historical documents allowed the researchers to estimate the strength of the magnetic storm that caused the September 1770 aurora.

"The magnetic storm on 17 September 1770 was comparable with or slightly larger than the September 1859 magnetic storm that occurred under the influence of the Carrington solar flare. The 1859 storm was the largest magnetic storm on record, in which technological effects were widely observed, "Ryuho Kataoka of NIPR says." It was lucky for us that the 1770 storm predated our reliance on electricity."

So how likely are such magnetic storms? " We are currently within a period of decreasing solar activity, which may spell the end for severe magnetic storms in the near future," Kataoka says. "However, we actually witnessed an extremely fast coronal mass ejection only several days ago [10 September 2017], which might be powerful enough to cause extreme storms. Fortunately, it just missed the Earth."

Regardless of the specific likelihood of another perfect magnetic storm, interdisciplinary historical and scientific collaborations are invaluable in providing important physical details that could help us to understand the greatest magnetic storms in history and prepare for any potential future event.
-end-
The article, "Inclined zenith aurora over Kyoto on 17 September 1770: Graphical evidence of extreme magnetic storm" was published in Space Weather at DOI: 10.1002/2017SW001690

Research Organization of Information and Systems

Related Aurora Articles:

How newly found tension sensor plays integral role in aligned chromosome partitioning
A Waseda University-led research found that oncogene SET/TAF1, which was found to be a proto-oncogene of acute myeloid leukemia (AML), contributes to proper chromosome partitioning as a tension sensor.
It's not aurora, it's STEVE
Researchers recently confirmed that the aurora-like lights known as STEVE are not actually aurora, but instead a unique phenomenon.
Streaks in aurora found to map features in earth's radiation environment
A special kind of streaked aurora has been found to track disturbances in near-Earth space from the ground.
Alternating currents cause Jupiter's aurora
An international research team has measured the system of currents that generates Jupiter's aurora.
Cell polarity -- An aurora over the pole
A recent research led by Assistant Professor Fumio Motegi, Principal Investigator at the Mechanobiology Institute at the National University of Singapore, has identified the master switch that triggers the symmetry breaking process in the zygotes of the nematode worm, Caenorhabditis elegans.
More Aurora News and Aurora Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...