[unable to retrieve full-text content] Space and Time News from Science Daily
- Published on Tuesday, 16 May 2017 14:18
In section 9. The Sun
Simulating Ellerman bomb-like events
Discovered exactly a century ago, Ellerman bombs are prominent brightenings in seen in H-alpha observations of newly emerging active regions (sunspots) on the Sun. These events play a crucial role in our understanding of the magnetic reconnection on the Sun, and cartoon scenarios have been drawn for decades. This this paper shows in a 3D MHD simulation how these events form in a self-consistent, way and highlights that solar convection pushes together magnetic field of opposite magnetic polarity and through this initiates reconnection in the photosphere of the Sun. The H-alpha emission derived from the simulations shows the same characteristic flame-like appearance as that found in observations.
- Published on Tuesday, 16 May 2017 14:17
In section 10. Planets and planetary systems
Evidence for depletion of heavy silicon isotopes at comet 67P/Churyumov-Gerasimenko
The heterogeneity of comets as carriers of primordial abundances is highlighted by the identification of the silicon isotopic ratio variations between comets – especially from this detailed, in situ study. Most importantly, the isotopic ratios point to different origins, espcially among the AGB stars and supernovae. While this has been known for some time from meteorites, this study is a first for the in situ sampling of a comet (thought to be the most primitive material in the solar system). It is important that the silicon is a far less chemistry-dependent tracer of the source(s) than the CNO isotopes.