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The solar magnetic activity cycle causes changes in the Sun on timescales that are relevant to human lifetimes. The minimum in solar activity that preceded the current solar cycle (cycle 24) was deeper and quieter than any other recent minimum. Using data from the Birmingham Solar-Oscillations Network (BiSON), we show that the structure of the solar sub-surface layers during the descending phase of the preceding cycle (cycle 23) was very different from that during cycle 22. This leads us to believe that a detailed examination of the data would have led to the prediction that the cycle-24 minimum would be out of the ordinary. The behavior of the oscillation frequencies allows us to infer that changes in the Sun that affected the oscillation frequencies in cycle 23 were localized mainly to layers above about 0.996Rsun, depths shallower than about 3000 km. In cycle 22, on the other hand, the changes must have also occurred in the deeper-lying layers.
The Suns variability is controlled by the progression and interaction of the magnetized systems that form the 22-year magnetic activity cycle (the Hale Cycle) as they march from their origin at $sim$55 degrees latitude to the equator, over $sim$19 ye
Since the discovery of the spectral peculiarities of their prototype alpha2 Canum Venaticorum in 1897, the so-called ACV variables, which are comprised of several groups of chemically peculiar stars of the upper main sequence, have been the target of
A recent article uncovered a surprising dynamical mechanism at work within the (vacuum) Einstein `flow that strongly suggests that many closed 3-manifolds that do not admit a locally homogeneous and isotropic metric textit{at all} will nevertheless e
Quantum mechanics does not provide a clear answer to the question: What was the past of a photon which went through an interferometer? Various welcher weg measurements, delayed-choice which-path experiments and weak-measurements of photons in interfe
In the study of planetary habitability and terrestrial atmospheric evolution, the divergence of surface conditions for Venus and Earth remains an area of active research. Among the intrinsic and external influences on the Venusian climate history are