Astrophysics is an area concerning various physical ranging from planetary sized systems, to galactic scale systems and beyond, that intersects various disciplines such as Newtonian dynamics, relativistic physics and particle physics processes.
For our latest developments/activities in this area, please see the listing below at the end of this article.
An exoplanet is a planet outside the Solar System. In the Milky Way galaxy, it is expected that there are many billions of planets (at least one planet, on average, orbiting around each star, resulting in 100–400 billion exoplanets), with many more free-floating planetary-mass bodies orbiting the galaxy directly.
We study the long-term dynamics of known multi-planet systems. This allow us to test the accuracy of the orbital parameters' determinations, as well as to understand how these systems evolved. We also look for the stable zones in the gaps between already-known planets in order to determine where is it possible to locate Earth-like planets.
See here a movie made by the PhD Animation on "Exoplanets Explained", for a review on the main observational methods used to detect exoplanets.
Detection of a second jet within the nuclear core of Mrk 501, S. Britzen, H. Olivares, Gopal-Krishna, F. Jaron, I. N. Pashchenko, E. Kun, F. K. Schinzel, J. Becerra González, D. Paneque, N. R. MacDonald; Monthly Notices of the Royal Astronomical Society (2026) stag291.
Locating the missing large-scale emission in the jet of M87* with short EHT baselines, B. Georgiev et al. (w/ H. Olivares); Astron. Astrophys. 709 (2026) A26; arXiv:2601.13356 [astro-ph.HE].
Spatially resolved polarization swings in the supermassive binary black hole candidate OJ 287 with first Event Horizon Telescope observations, J. L. Gómez et al. (w/ H. Olivares); Astron. Astrophys. 705 (2026) A23.
Ring Asymmetry and Spin in M87*, V. Bernshteyn et al. (w/ H. Olivares); Astron. Astrophys. 1000 (2026) 2, 231; arXiv:2601.00394 [astro-ph.HE].
Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations, Saurabhn et al. (w/ H. Olivares); Astron. Astrophys. 706 (2026) A27, arXiv:2512.08970 [astro-ph.HE].
We got together on May 20th 2026 at Etevaldo's favourite restaurant in Aveiro (O Telheiro), to celebrate his 4.5 years in Gr@v. In the same day we had an excellent seminar from Hryhorii Ovcharenko, visiting from Prague. Etevaldo is now starting a post-doctoral position in Brazil. Many thanks, Etevaldo, for being with us. See you soon!
Gravitational-wave (GW) observations have significantly advanced our understanding of stellar-origin compact objects. Current detectors could, in principle, also observe exotic compact objects (ECOs) acting as black-hole mimickers and interacting only gravitationally with visible matter.
Neutron stars offer unique natural laboratories for probing the interaction between dark matter and baryonic matter — a central open question in modern astrophysics and high-energy physics. In this talk, I will present our recent work modeling dark matter as an ultralight bosonic field that accretes onto neutron stars, forming composite objects — fermion-boson stars — bound through gravity.
In April 2026 we received the visits of Maryem Jemri (Rabat) and Justin Feng (Prague). Thank you for your seminars and the great scientific interactions!