Tinted detail of a photo: Fisheye view of bright green aurora bands swirling across a starry night sky above a snowy curved horizon, with a small lit building at the right edge.
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Solar-Terrestrial Sciences

Science Posts

Why faculae “vanish” on active Suns

Why faculae “vanish” on active Suns

The Earth’s primary energy source is the radiative energy flux (i.e., the Total Solar Irradiance, TSI) from the Sun. Understanding the TSI or the solar irradiance output in particular wavelengths is important, as it is crucial for sustaining life of metabolisms on Earth and in answering the question of how life emerged on Earth. It …[Read More]

Employing J burst observations made by LOFAR to determine the properties of large coronal loops

Employing J burst observations made by LOFAR to determine the properties of large coronal loops

Large coronal loops around one solar radius in altitude are an important connection between the solar wind and the low solar corona. However, their plasma properties are not well studied, as standard X-ray and UV techniques are not suited to these low-density environments. How does temperature, pressure, and magnetic field strength evolve along these loops? …[Read More]

Reflection after the investigation of the direct First Parker Solar Probe Observation of the Interaction of Two Successive ICMEs

In Heliophysics there is a scarcity of in-situ buoys that allows us to monitor and track the solar wind changes in our Sun’s atmosphere, the heliosphere. NASA’s Parker Solar Probe (PSP) mission is one of those buoys that, together with Solar Orbiter (SolO, ESA/NASA Collaboration), is bringing a breath of fresh air in the effort …[Read More]

Initiation and Heliospheric Evolution of a stealthy solar eruption

A schematic of the ICME flux rope cross-section and the large-scale magnetic structure draping about the ICME obtained based on the PSP observation.

In the early 1970s, when Coronal mass ejections (CMEs), massive eruptions of magnetized solar plasma into interplanetary space, were first discovered, they were assumed to be always associated with the energetic solar phenomenon like solar flares, prominences, etc. With improved coronagraphic and multi-wavelength observational instruments, a class of CMEs emerging from the streamers was found …[Read More]

New auroral dunes discovered through citizen science

New auroral dunes discovered through citizen science

The region of the Earth’s atmosphere lying at altitudes between about 80 and 120 km, corresponding to the mesosphere–lower thermosphere–ionosphere (MLTI), is often referred to as the “ignorosphere”, because its observation is so challenging that only a handful of measurements of its composition, temperature and other physical parameters have been obtained over the last few decades. …[Read More]

Chasing solar storms as an early career scientist

Hello! My name is Erika Palmerio and I am a newly qualified Dr in space physics from the University of Helsinki, Finland. In this blog post I will talk about my PhD research and my future career plans. The title of my PhD dissertation is “Magnetic structure and geoeffectiveness of coronal mass ejections”. Coronal mass …[Read More]

Web-based Tools for Forecasting Solar Particle Events and Flares

Web-based Tools for Forecasting Solar Particle Events and Flares

The presence of Solar Energetic Particles (SEPs) poses a serious health risk to humans in space, can result in increased radiation doses for high-latitude aircraft flights and constitutes a serious hazard for the micro-electronics and other hardware elements of satellites, aircraft and launchers. These groups of end users need reliable forecasts of possible enhancements in …[Read More]