Vorträge, Kolloquien

17:00 Uhr Via Zoom, Registrierung , Otto-Haxel-Hörsaal
Prof. Dr. Johan Rockström Director of the Potsdam Institute for Climate Impact Research and Professor in Earth System Science at the University of Potsdam

Sustainability in the Anthropocene: Governing the Global Commons within Planetary Boundaries

Rising human pressures on the planet during the Great Acceleration phase from the 1950s onwards, has pushed the Earth system into a new geological Epoch, the Anthropocene. This is the age of the human enterprise, where our modern economy triggers impacts that exceed, in both pace and scale, the natural variations, stresses and shocks from Earth's orbit around the Sun, volcanic eruptions, and Earthquakes. Today, science is forced to consider the real risk of us, the modern world, destabilising the entire planet, potentially pushing the Earth system away from its equilibrium state, the Holocene, that has been the prerequisite for the development of modern human civilisations since we left the last Ice Age some 12,000 years ago. Nine of 15 known climate tipping elements are showing signs of approaching tipping points, and Earth system analyses show unequivocal scientific evidence that a stable climate on Earth, requires that other Earth system regulating processes and systems are kept within a safe operating space, i.e., scientific targets for a resilient and stable planet (ranging from biosphere, to climate and cryosphere). The Planetary Boundaries framework provides such safe targets. Together, the scientific evidence of the Anthropocene, tipping elements, risks of interacting cascade effects, and their impacts on humans, calls for a new paradigm of planetary stewardship, setting the frontier of sustainable resource science in the Anthropocene, and being framed around our ability to govern the global commons within planetary boundaries, as a pathway towards delivering on the Sustainable Development Goals and world development through this century and beyond.

14:00 Uhr Online, SR 1.403
Prof. Mark Saffman Department of Physics at UW Madison

tba

16:00 Uhr Zoom, 973 7719 2005; please contact the host (Richard Tuffs, MPIK) for the meeting password
Dr. Frank Eisenhauer MPI fuer Extraterrestrische Physik

A new era of Interferometry with GRAVITY(+)

https://zoom.us/j/97377192005?pwd=OUZPR1Z3ZGc5WDZPYW1SakEzV1pvQT09 The GRAVITY instrument has enabled major steps forward in infrared interferometry, by phase-referenced imaging at milli-arcsecond resolution, with a sensitivity increase by factor thousands, 30-100 micro-arcsecond astrometry, and few micro-arcsecond differential spectro-astrometry. We give an overview of the technology behind GRAVITY and highlight the game-changing results from the first three years of operation. Our presentation takes us from nearby exoplanets all the way to distant quasars, with special focus on the Galactic Center, the first precision tests of Einstein?s theory of General Relativity around massive black holes, and tests of the massive black hole paradigm on scales of 3-6 Schwarzschild radii. The GRAVITY+ project will soon boost optical interferometry to the next level, opening up the extragalactic sky for milli-arcsecond resolution interferometric imaging, and providing ever higher contrast for the observation of exoplanets. This will be made possible with wide-field fringe-tracking, new state-of-the-art adaptive optics, laser guide stars, and performance improvements of GRAVITY and the VLT(I) infrastructure. We discuss some of the discovery space opening up with GRAVITY+, for example the detailed view on AGN at cosmic dawn, the detection and characterization of exoplanets and their atmospheres, the spin of the Galactic Center black hole, and microlenses tracing the Milky Ways dark components. Dr. Eisenhauer is hosted by Dr. Diederik Kruijssen (kruijssen@uni-heidelberg.de)