Special issue “Recent progress in the physics of the Sun and heliosphere”, by E. Kontar and I. Ballai

The present Special Issue published in Advances of Space Research contains a collection of peer-reviewed contributions that builds on the recent observational and theoretical advances, surveying the existing knowledge in reconnecting magnetic fields, flares and plasma heating, the generation, evolutions and dynamics of small-scale solar jets, dynamics in various layers of the solar atmosphere, recent advances in coronal spectroscopy and the evolution of the solar wind inspired by European Solar Physics Meeting ESPM-16 conducted online in September 2021 . Of course, the topics presented here do not cover, by far, the aspects that nowadays constitute the multi-faceted solar physics discipline. Nevertheless, we hope that the present contributions will give readers an overview about where some of our knowledge of solar physics currently stands and what are we aiming for.

This Special Issue has tremendously benefited from the help and guidance by Dr. Peggy Ann Shea, ASR Co-Editor for Special Issues. The Guest Editors are grateful to all the authors for their valuable time and efforts, without which the publication of this issue would have been impossible. We also thank all the referees for their hard work and invaluable advice, that profoundly improved the papers contained in this issue.

The special issue contains the following papers:

PREFACE: Recent progress in the physics of the Sun and heliosphere
by Eduard Kontar, Istvan Ballai

Magnetic reconnection on the Sun: ESPD Senior Prize Lecture
by Eric Priest

Small-scale solar jet formation and their associated waves and instabilities
by Samuel Skirvin et al.

Coronal spectroscopy: Probing sources of slow solar wind in active regions, and the early phases of solar flares
by Louise K. Harra

A spectroscopic measurement of high velocity spray plasma from an M-class flare and coronal mass ejection
by Peter R. Young

Where is the base of the Transition Region? Evidence from TRACE, SDO, IRIS and ALMA observations
by Costas E. Alissandrakis

Evolutionary features of polar and non-polar coronal holes during solar cycle 24 and the rising phase of cycle 25
by Olga Andreeva

The potential of Meudon spectroheliograph for investigating long term solar activity and variability
by Jean-Marie Malherbe et al.

Modeling of chromospheric features and dynamics in solar plage
by Sanja Danilovic

Numerical simulations of a continuously injected relativistic electron beam relaxation into a plasma with large-scale density gradients
by Vladimir Annenkov, Evgeniia Volchok

Shocks and instabilities in the partially ionised solar atmosphere
by Andrew Hillier and Ben Snow

The north-south asymmetry of active regions of different magneto-morphological types in solar cycles 23 and 24
by Anastasiya Zhukova, et al.

Sun CubE OnE: A multi-wavelength synoptic solar micro satellite
by L. Giovannelli et al.

New insights from cross-correlation studies between solar activity indices and cosmic-ray flux during Forbush decrease events
by Mihailo Savić et al.,

The characteristics of flare- and CME-productive solar active regions
by Ioannis Kontogiannis

On the time lag between solar wind dynamic parameters and solar activity UV proxies
by R. Reda, L. Giovannelli, T. Alberti

A new catalogue of solar flare events from soft X-ray GOES signal in the period 1986–2020
by Nicola Plutino et al.,