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Physical processes involved in the acceleration of stellar winds are essential in astrophysics as such winds are a mass loss process for stars. Hypothesis for stellar winds are difficult to check with experimental data in any other star but the Sun and even the processes of solar wind dynamics are poorly understood. Since the proposal by Parker of the stationary expansion of the solar atmosphere, the existence of the solar wind has been extensively demonstrated from data acquired from different missions in the Heliosphere. However, in-situ data showing that solar wind accelerates with the distance were still missing. Here we show the evolution of the solar wind speed distribution function with the heliocentric distance from 16 R⊙ to 172 R⊙ using Parker Solar Probe data. We observe that solar wind is accelerated until at least 60 R⊙, more than 20 R⊙ away than expected from previous studies. Below ∼ 25 R⊙ the subalfvenic wind dominates and is negligible from 35 R⊙ onwards. Here we find that the slow and fast winds are as mixed in the distribution function below 25 R⊙ as at 1 AU. Our findings provide empirical support for the models of solar wind dynamics.

The solar storms happened in early August 1972 have been recently described as an example of a space weather event due to its technological impacts. Besides the interest of this event for the space weather community, these storms were extensively analyzed by the scientific community in 1970s and 80s due to their relevance considering the enhanced levels of solar activity and also their interplanetary consequences. The passage of several interplanetary shocks was observed in Pioneers 9 and 10 data and also in Pognoz-1, Prognoz-2 and HEOS-2 data, making this event particularly suitable for the study of the evolution of the solar ejections in the Heliosphere. This work starts reviewing the papers on the interplanetary scenario during this event. Then, we revisit their conclusions considering the scientific advances since that date and finally go ahead in the analysis of the event.

SMOS is an Earth observing satellite that is been adapted to provide full polarization observations of the Sun at 1.4 GHz 24 hours a day. Its solar radio observations from the last decade will be released to the community by the middle of this year. In this presentation we show the capabilities of SMOS as a solar radio observatory and compare some of the most relevant radio bursts with data from GOES, LASCO, SDO and RSTN. We show how SMOS responds to different kinds of solar flares depending on their x-ray flux, and the kind of mass ejection or solar dimming that they have produced, if any. In addition to this we also show the potential of SMOS as a space weather tool to monitor GNSS satellites signal fades and to provide an early warning of Earth-directed coronal mass ejections.

Our research is based on the analysis of the solar wind speed distribution provided by the SWEAP instrument onboard the Parker Solar Probe spacecraft (PSP).The dataset provide measurements from 16 to 202 solar radii, covering the nine first orbits of the PSP. To obtain more detailed results we have sliced the radial distancein smaller distance intervals to analyze the solar wind speed distribution within each one. The results show an acceleration from the vicinity of the Sun until a radialdistance around 100 solar radii. From this distance onward, the speed shows a constant speed until the arrival to the Earth. &nbsp