The black hole theorist and cosmologist Stephen Hawking passed away at the age of 76. Stephen Hawking distinguished himself not only as a brilliant scientist, with remarkable contributions such as the discovery of black hole evaporation, but also as an active science communicator with best selling books, most notably A brief history of time.
Recent advances in radio telescopes in sensitivity, response time, and wavelength coverage have opened a wealth of new research opportunities. This is particularly the case for transients, where high sensitivity and rapid response is crucial. I will describe how radio observations of two classes of objects are helping to further our understanding of jet physics.
The satellite Venus Express (2006-2015), together with the Japanese spacecraft Akatsuki (still in orbit) and ground-based campaigns, are unveiling our neighbor planet. At the same time, those new measurements put in evidence the complexity and the high variability of the Venus atmosphere, opening new scientific questions (e.g.
Quasi-Stellar Objects (QSOs) are active galactic nuclei so powerful, that their luminosity can surpass that of the host galaxy, making the observation of the latter extremely difficult or even impossible. Usually QSOs appear on images as point-like sources, what, together with the enormous distances, makes them excellent objects for the materialization of reference systems.
Gr@v member T. Boekholt visited Tokyo University in Tokyo, Japan. His visit was hosted by Prof. Michiko Fujii, head of the computational astrophysics group at the Astronomy Department. T. Boekholt started a new collaboration on studying planetary dynamics and he presented his recent publication on the Slingshot mechanism in Orion.
"SKA days PT" took place last 6 and 7 of February, at Covilhã and Lisbon, an initiative to promote the Square Kilometer Array (SKA) - the world's largest radio telescope - among the Portuguese scientific and business communities.
SKA project has the participation of 19 countries, in the case of Portugal it is via the infrastructure ENGAGE SKA, which is a consortium composed by the Instituto de Telecomunicações, the Universities of Aveiro (Gr@v), Porto and Évora, and the Polytechnic Institute of Beja.
Greybody factors are frequency dependent quantities that measure the deviation from the perfect black body spectrum of Hawking radiation, and they provide us with valuable information about the near horizon structure of black holes. In
addition, when black holes are perturbed the geometry of spacetime undergoes dumbed oscillations.
DOPPLER (DevelOpment of PaloP knowLEdge in Radioastronomy), coordinated by Dr. Valério Ribeiro of Gr@v (University of Aveiro), is a recently funded FCT and the Aga Khan Development Network project.
Our group coordinated the "Numerical Relativity and High Energy Physics" IRSES network (2012-2015). Here is a list of the global network meetings organized: