activity
20172020
most citedTemporal and Spatial Evolutions of a Large Sunspot Group and Great Auroral Storms around the Carrington Event in 1859

98 citations · 301 across the 8 of their papers we have counts for

collaborators

8 papers

astro-ph.SR2020★ 14 cited

The intensity and evolution of the extreme storms in January 1938

Hisashi Hayakawa, Kentaro Hattori, Alexei A. Pevtsov +7

Major solar eruptions occasionally direct interplanetary coronal mass ejections (ICMEs) to Earth and cause significant geomagnetic storms and low-latitude aurorae. While single ext…

physics.space-ph2020★ 13 cited

The Extreme Space Weather Event in February/March 1941

Hisashi Hayakawa, Sean P. Blake, Ankush Bhaskar +3

Given the infrequency of extreme geomagnetic storms, it is significant to note the concentration of three extreme geomagnetic storms in 1941, whose intensities ranked fourth, twelf…

astro-ph.SR2019★ 98 cited

Temporal and Spatial Evolutions of a Large Sunspot Group and Great Auroral Storms around the Carrington Event in 1859

Hisashi Hayakawa, Yusuke Ebihara, David M. Willis +10

The Carrington event is considered to be one of the most extreme space weather events in observational history within a series of magnetic storms caused by extreme interplanetary c…

astro-ph.SR2019★ 3 cited

A Transit of Venus Possibly Misinterpreted as an Unaided-Eye Sunspot Observation in China on 9 December 1874

Hisashi Hayakawa, Mitsuru Sôma, Kiyotaka Tanikawa +6

Large sunspots can be observed with the unaided eye under suitable atmospheric seeing conditions. Such observations are of particular value because the frequency of their appearanc…

astro-ph.SR2019★ 25 cited

Occurrence of Great Magnetic Storms on 6-8 March 1582

Kentaro Hattori, Hisashi Hayakawa, Yusuke Ebihara

Although knowing the occurrence frequency of severe space weather events is important for a modern society, it is insufficiently known due to the lack of magnetic or sunspot observ…

astro-ph.SR2018★ 32 cited

A Great Space Weather Event in February 1730

Hisashi Hayakawa, Yusuke Ebihara, José M. Vaquero +9

Aims. Historical records provide evidence of extreme magnetic storms with equatorward auroral extensions before the epoch of systematic magnetic observations. One significant magne…

physics.space-ph2018★ 55 cited

The Great Space Weather Event during February 1872 Recorded in East Asia

Hisashi Hayakawa, Yusuke Ebihara, David M. Willis +9

The study of historical great geomagnetic storms is crucial for assessing the possible risks to the technological infrastructure of a modern society, caused by extreme space-weathe…

astro-ph.SR2017★ 61 cited

Long-Lasting Extreme Magnetic Storm Activities in 1770 Found in Historical Documents

Hisashi Hayakawa, Kiyomi Iwahashi, Yusuke Ebihara +8

Dim red aurora at low magnetic latitudes is a visual and recognized manifestation of geomagnetic storms. The great low-latitude auroral displays seen throughout East Asia on 16-18…