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Solar activity around AD 775 from aurorae and radiocarbon
A large variation in 14C around AD 775 has been considered to be caused by one or more solar super-flares within one year. We critically review all known aurora reports from Europe as well as the
Variations of 14C around AD 775 and AD 1795 – due to solar activity
The motivation for our study is the disputed cause for the strong variation of 14C around AD 775. Our method is to compare the 14C variation around AD 775 with other periods of strong variability.
Sunspot numbers based on historic records in the 1610s: Early telescopic observations by Simon Marius and others
Hoyt & Schatten (1998) claim that Simon Marius would have observed the sun from 1617 Jun 7 to 1618 Dec 31 (Gregorian calendar) all days, except three short gaps in 1618, but would never have detected
Presumable European aurorae in the mid AD 770s were halo displays
The interpretation of the strong 14-C variation around AD 775 as one (or several) solar super-flare(s) by, e.g., Usoskin et al. (2013) is based on alleged aurora sightings in the mid AD 770s in
A review of East Asian reports of aurorae and comets circa AD 775
Author(s): Chapman, J; Neuhauser, DL; Neuhauser, R; Csikszentmihalyi, M | Abstract: © 2015 WILEY-VCH Verlag GmbH a Co. KGaA, Weinheim. Given that a strong 14C variation in AD 775 has recently been
New sunspots and aurorae in the historical Chinese text corpus? Comments on uncritical digital search applications
We review some applications of the method of electronic searching for historical observations of sunspots and aurorae in the Chinese text corpus by Hayakawa et al. etc. However, we show strong
Interpretation of the historic Yemeni reports of supernova SN 1006: early discovery in mid-April 1006 ?
The recently published Yemeni observing report about SN 1006 from al-Yamani clearly gives AD 1006 Apr $17 \pm 2$ (mid-Rajab 396h) as first observation date. Since this is about 1.5 weeks earlier than
‘Novae, supernovae, or something else?’ – (super-)nova highlights from Hoffmann & Vogt are quite certainly comets (ad 668 and 891)
Galactic novae and supernovae can be studied by utilizing historical observations, yielding explosion time, location on sky~etc. Recent publications by Hoffmann & Vogt present CVs, supernova