A great review of the proposed mechanisms for switchback formation in the solar wind. These strong deflections in the local magnetic field are ubiquitous close to the Sun and have been linked to the heating and acceleration of the solar wind. arxiv.org/pdf/2604.16166
The FIP effect remained consistent between the two atmosphere profiles. However, changes to the acoustic flux and increases in choromspheric turbulence could suppress fractionation, leading to variability in the FIP effect within flaring loops.
New paper day! Andy To et al. studied the elemental fractionation in coronal loops with FIPpy, comparing the First Ionisation Potential (FIP) effect produced in an initial VAL-C chromosphere versus a heated chromosphere
following impulsive nanoflare-like events: arxiv.org/abs/2604.13174
It's paper time ! 🎉
The article got accepted yesterday and is now available on arXiv, thread presenting the main results below ! ✨
arxiv.org/abs/2603.01979
☄️ #stellarastro
Image from ESA's Solar Orbiter (EUI/FSI) of an S-shaped coronal hole, stretching from bottom left to top right. We are attempting to capture the sources of the fast solar wind detected insitu at the spacecraft with high resolution imagery and spectroscopy. Supported by Hinode and IRIS. ☀️🔍💨
Visiting @sy-brt.bsky.social et al. at the Catania observatory where we discussed the activity of Sun-like stars and the links between ESA's Solar Orbiter and PLATO missions. After a few stormy days, I finally made it to the observatory for sunny views of Etna 🏔️ and a look at the solar telescope ☀️
Ever wondered what powers a solar flare? 💥
Solar Orbiter is finally giving us answers to this long-standing mystery.
The mission caught a 'magnetic avalanche' on the surface of the Sun just before a flare was released.
🔭🧪1/3
Are you (or do you know of) an undergrad with an interest in solar physics? Check out the Leiden/ESA Astrophysics Program for Summer Students (LEAPS 2026). Myself, Andy To and Henrik Eklund invite you to come work with us at ESTEC on "Catching the Solar Wind in Action". leaps.strw.leidenuniv.nl#none
New paper day! 🔥 George Cherry et al. use the Most Significant Frequency decomposition to investigate shocks, jets, and swirls in the Sun's atmosphere. We find the contribution of 3.5 and 5 mHz signals to be up to 50% of the
overall wave power. Published in A&A: www.aanda.org/articles/aa/...
🔭 Until now, observing the inner regions of the Sun’s enigmatic atmosphere – the corona – was close to impossible.
🛰️🛰️☀️ The satellite duo making up @esa.int’s Proba-3 mission fills this observation gap by creating artificial solar eclipses in orbit 👉 www.esa.int/Enabling_Sup...
2025 was a landmark year for Europe in space 🚀
From celebrating 50 years of ESA to new missions and scientific breakthroughs, the year reaffirmed Europe’s leadership in science, exploration, climate action and innovation.
🎥 Watch our highlights video:
youtu.be/obJbRWZ8f1Y?...
📣 New outreach poster: ESA’s Vigil Mission ☀️💨🛰️💨🌍
The Space-weather “reporter” will monitor the Sun from the Lagrange point 5, reporting 24/7 solar activity days before it reaches Earth.
www.esa.int/var/esa/stor...
Black disk surrounded by a greenish solar corona
Yellow Sun surrounded by a greenish disk of solar corona surrounded by a bigger reddish disk of solar corona
🛰️🤩🎂 The #Proba-3 satellite duo, creators of #solareclipses, have just celebrated their first anniversary in space! The multitude of images already provided by #ASPIICS on board is a source of great joy for the Royal Observatory of Belgium, its principal investigator. www.astro.oma.be/en/...
Published in @aanda-journal.bsky.social 😍: www.aanda.org/articles/aa/...
☀️Flying through the strongest solar storm ever recorded
No communication or navigation, faulty electronics, collision risks. ESA mission control teams faced a scenario unlike any before. Fortunately, this nightmare unfolded not in reality, but as part of the simulation!
www.esa.int/Space_Safety...
Comparison at the time of Orbiter:
Beautiful double erruption in 304A observed by GOES/SUVI and Solar Orbiter over the east-limb (slightly later) in the low-latency data.
Photograph of the bottom half of the Sun, with a highlighted square region around the Sun's south pole. Taken in ultraviolet light, the image shows the hot gas in the Sun's outer atmosphere, the corona, glowing yellow as it extends outwards in threads and loops from the Sun. Credit: ESA & NASA/Solar Orbiter/EUI Team, D. Berghmans (ROB)
Are you an early-career scientist or engineer?
Then the ESA Research #Fellowships in Space Science might be just the right opportunity for you.
Check out the programme details here 👉 www.cosmos.esa.int/web/space-sc... 🔭 🧪 ☄️
The Alfvén radius is linked to the solar wind mass and magnetic flux. The wind magnetisation parameter (~ratio of mag/mass flux), is used to understand this dependence. Our results follow the trends from MHD wind simulations, but had an offset that is likely due to 3D effects and turbulence. (5/8)
Towards maximum activity, the heliospheric current sheet became complex and the solar wind sources moved towards the active latitudes. So, for example, an encounter of PSP that spends more time in the solar wind near current sheets will have a smaller Alfvén radii on average. (7/8)
A very dipolar magnetic field became inclined to the rotation axis. (6/8)
The heliospheric current sheet became warped by the emergence of active regions. (5/8)
The evolution of the coronal magnetic field during the solar cycle, strongly influenced the magnetic connectivity of PSP. Each encounter is different, which obscures our perception of the average Alfvén radius. Near minimum, the wind measured by PSP originated closer to the Sun's poles. (4/8)
We mapped the wind back to its source using the Parker spiral and a potential field source surface model. The Alfvén surface was modulated by structure in the corona. Smaller near current sheets and pseudo-streamers, larger near the dipole axis and expanding magnetic field. (3/8)
Using hourly measurements from the SWEAP and FIELDS suites, we mapped PSP to the Alfvén surface with a Parker spiral. Each encounter had a distribution of radii. The longitudinal-average reduced the bias from individual wind streams, the average grew from 10-16 solar radii. (2/8)
Side project day! NASA's Parker Solar Probe (PSP) has been exploring the near-Sun enviroment since the start of solar cycle 25. Now passing maximum activity, how has the shape and size of the Sun's Alfvén surface evolved since? arxiv.org/abs/2509.07088 (1/8)
New paper day! Metcalfe et al. review the evidence for weakened magnetic braking around the Sun's age by homogenizing the stellar parameters from previous studies that constrained the wind braking of stars with observed magnetic fields and x-ray fluxes (proxy for mass-loss): arxiv.org/pdf/2509.03717
3D view of this plot:
