84 citations · 311 across the 20 of their papers we have counts for
18 papers · 1 filter
Do the planets cause the sunspot cycles?
Lauri Jetsu
The mainstream dynamo models predict that the sunspot cycle is non-stationary and stochastic. The official Solar Cycle Prediction Panel forecasts only the ongoing sunspot cycle bec…
About ten stars orbit eclipsing binary XZ And
L. Jetsu
A third body in an eclipsing binary system causes regular periodic changes in the observed (O) minus the computed (C) eclipse epochs. Fourth bodies are rarely detected from the O-C…
Say hello to Algol's new companion candidates
L. Jetsu
Constant orbital period ephemerides of eclipsing binaries give the computed eclipse epochs (C). These ephemerides based on the old data can not accurately predict the observed futu…
Topological changes in the magnetic field of LQ Hya during an activity minimum
Jyri J. Lehtinen, Maarit J. Käpylä, Thomas Hackman +6
Previous studies have related surface temperature maps, obtained with the Doppler imaging (DI) technique, of LQ Hya with long-term photometry. We compare surface magnetic field map…
Long-term spot monitoring of the young solar analogue V889 Her
T. Willamo, T. Hackman, J. J. Lehtinen +6
Starspots are important manifestations of stellar magnetic activity. By studying their behaviour in young solar analogues, we can unravel the properties of their magnetic cycles. T…
Real light curves of FK Comae Berenices: Farewell flip-flop
L. Jetsu
For seven decades, the widely held view has been that the formation, the migration and the decay of short-lived starspots explain the constantly changing light curves of chromosphe…