How much oxygen has escaped to space since the Great Oxidation Event? And how has the escape rate changed over the last 2.5 billion years? Maria Luisa Alonso Tagle and co-workers found out. This research was published in JGR - Space Physics: doi.org/10.1029/2025...
Herbert Gunell
@herbertgunell.se
Space scientist at Umeå University. Draws rhinos. https://www.herbertgunell.se/
How are charged particles accelerated in space? A new paper reports that at comet 67P, accelerated cometary ions are organised in jets (@charlottestalks.bsky.social, R. Doyle-Morgan, @herbertgunell.se, E. Krämer, T. Karlsson, A. Möslinger, C. Simon Wedlund, and M. Volwerk doi.org/10.3847/1538...)
Do magnetosheath jets cause surface waves on the magnetopause? Are the jets themselves waves? A new paper by Eva Krämer of @umeauniversitet.bsky.social throws some light on these questions: doi.org/10.1093/mnra... Rhinos talk about it
One thing we really want to understand better is how energy is transferred between large and small scales in a plasma around a comet. Actually not just around a comet, but everywhere else too. Therefore, we studied of Langmuir waves at comet 67P: doi.org/10.1051/0004.... @aanda-journal.bsky.social
How does the solar wind composition influence a comet magnetosphere? The magnetosphere expands when the alpha particle fraction increases. Anja Möslinger and others showed that this is because protons are better than alphas at keeping it small @aanda-journal.bsky.social. doi.org/10.1051/0004...
Waiting for a comet in space ☄️ Targeting launch in 2029, #CometInterceptor will be parked in space, waiting for an as-yet-undiscovered comet to come by. Discover more about this ESA-led mission in collaboration with JAXA 👉 www.esa.int/Science_Expl... 🔭
Traditionally, PhD theses are nailed to a wall at the university library 3 weeks before the dissertation. Here's Sara Nesbit-Östman's PhD thesis about the bow shock of Mars, attached to the wall at @umeauniversitet.bsky.social, using an unusually long nail.
We wanted to find out how important magnetosheath jets really are. And in a new paper by Eva Krämer at Umeå University it is shown that jets carry about half of the kinetic energy in the quasiparallel magnetosheath of Earth. doi.org/10.1029/2025...
☄️ #CometInterceptor will target a pristine comet entering the inner Solar System for the first time. The mission will investigate if these comets are different from the ones we know and if they contributed to the appearance of life on Earth, among others. Read more 👉 www.esa.int/Science_Expl... 🔭
Top five questions Comet Interceptor will help answer
Comet Interceptor will target a pristine comet entering the inner Solar System for the first time. Such objects are difficult to get close to because we can only detect them when they fly near the Sun...
esa.int
Three PhD student positions in Space Physics are available at Umeå University in Sweden @umeauniversitet.bsky.social. Apply 23 May 2025 at the latest. For more information see www.umu.se/en/work-with...
Jets were recently found at Mars, and we made a statistical study, using data from the Maven spacecraft, to find out more about them. You may read the paper here: doi.org/10.1051/0004...
We wanted to know what makes the Martian bow shock asymmetric. We found that at any one instant it can be quite asymmetric, but on average these asymmetries cancel out to a large extent. The bow shock is actually quite dynamic. Read the new paper by Sara Nesbit-Östman et al. doi.org/10.1051/0004...
There's a new review paper about the Magnetosheath Jets, and other jets, out now by Eva Krämer and others. doi.org/10.1007/s112...
Last day before the holiday break and it's time to complete that paper.
We have two PhD student positions related to the icy moons, advertised now at Umeå University in Sweden: Modeling Water Plumes on Icy Moons. Supervisor: Dr. Shahab Fatemi www.umu.se/en/work-with... Aurora on Jupiter's Moon Ganymede. Supervisor: Dr. Herbert Gunell www.umu.se/en/work-with...
Are waves heating the plasma at Venus? Gabriella Stenberg Wieser used data from the Venus Express spacecraft to find out. The energy density of the waves is high enough that they could cause the observed heating. The study was published in JGR Space Physics: doi.org/10.1029/2024...