Raum: Cygnus + Draco
The solar butterfly diagram: from a low-dimensional model to new proxies of solar activity [mehr]

MPS Seminar: Seismic investigations of the Lithosphere (J.L. Dimech, New Zealand)

Rosetta Seminar: 67P Outbursts (J.B. Vincent)

Planetary Group Seminar: Exploring the Perimeter of the Heliosphere using IBEX and Voyager Observations (G. Glöckler)

Forty-five years after they were launched, the two deep space probes of the Voyager Interstellar Mission are now exploring the distant nose region of the heliosphere in two different directions at distances from ~85 to ~135 astronomical units from the sun. Voyager 1 (V1) measurements of the magnetic field, plasma waves and energetic particles, have revealed numerous surprises, forcing a rethinking of our concepts of the heliosphere and its interaction with the local interstellar medium. Most heliospheric researchers now believe that V1 entered interstellar space in late August 2012 and are constructing models based on this assumption. However, we find, using pressure balance and measurements of the low energy neutral hydrogen atoms spectrum, that the strength of the magnetic field that VI is currently observing is only half of the strength of the local interstellar field. This and other observational evidence leads us to conclude that Voyager 1 is not yet in interstellar space but rather remains in a most unusual region of the heliosheath. [mehr]

MPS Seminar: Seismic investigations of the Lithosphere, western North Island, New Zealand (J. L. Dimech)

Ellerman bombs and UV bursts are transient brightenings that are ubiquitously observed in the lower atmospheres of active and emerging flux regions. While some Ellerman bombs display clear UV burst signatures, not all have correlated UV signal or vice versa, suggesting the underlying atmospheric and magnetic properties may differ between events. As both are believed to pinpoint sites of magnetic reconnection in reconfiguring fields, understanding their occurrence and detailed evolution may provide helpful insights in the overall evolution of active regions. Here we present results from observations and inversions of SST/CRISP and CHROMIS, as well as IRIS data of these transient events. At unprecedented spatial resolution the CHROMIS Ca II H & K observations reveal dynamic fine structure suggesting a plasmoid-mediated reconnection process. We investigate several cases, combining information from the Mg II h & k and Ca II 8542Å and H & K lines in order to infer the temperature stratification and magnetic field configuration within which these events occur. I’ll address the difficulties of successfully inverting their Si IV profiles and will discuss our results in light of the current debate on the connection between UV bursts and Ellerman bombs, their occurrence heights and in particular the temperatures that they may (or may not) reach. [mehr]
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