The characterization of exoplanetary atmospheres is one of the most active research fields in modern astrophysics, made possible by the development of dedicated instruments and techniques. The basic idea of this research is quite simple: obtaining spectroscopic observations of stars with planets during the transit of the planet in front of its star, which is the moment when part of
Most stars behave like enormous dynamos, producing intense magnetic fields within them. These magnetic fields then interact with the plasma that constitutes the star’s interior and atmosphere, in a constant tug of war where the prevailing force dominates the dynamics. In the outer region of stars, from the photosphere to the corona, the pressure exerted by the gas is less
One of the most interesting aspects of exoplanetary science is the possibility of studying worlds that are not present in our Solar System (at least, not today). Some of these exoplanets possess such extreme properties that they are of great scientific interest. This is certainly the case for the Ultra-Hot Jupiter KELT-9b. It is a gas giant with a mass
Despite the wide array of telescopes and satellites available to the astronomical community, there is a type of radiation to which we are virtually blind: the extreme UV band. This is high-energy radiation with a wavelength that ranges from the Lyman-α emission, caused by hydrogen atoms whose electron transitions from the innermost orbital (the ground state) to the second (n=2),
The study of exoplanetary systems of stars with an age of a few hundred million years can teach us a great deal about the early and crucial evolutionary phases of planetary systems. Processes such as planetary migration, which causes planets to modify their distance from the central star, the circularization of orbits, and planetary photoevaporation play a fundamental role in
One of the most interesting possibilities offered by the research on exoplanets is the ability to study types of planets that are not present in the Solar System. Among these are the “hot” and “warm” Neptunes. These are planets the size of Neptune that orbit very close to their stars (with an orbital period shorter than 10 days), with an
Every sci-fi enthusiast, especially Star Wars fans, has wondered whether planets orbiting two stars, like Tatooine, can exist in reality. This is actually an important question in astronomy: It has been estimated that in the Milky Way, one-third of low-mass stars are in binary systems. Therefore, to fully understand the population of planets in our Galaxy, it is necessary to
The study of the orbital parameters of exoplanets can shed light on their past. An important quantity in this context is the eccentricity of elliptical orbits, which is the ratio between the distance of the foci over the major semiaxis. Eccentricity is equal to zero when the ellipse degenerates into a circle or equal to one when it degenerates into
One of the lessons we have learned after two decades of exoplanetary science, primarily from the diversity of exoplanets discovered to date, is that various properties of exoplanets depend on the characteristics and evolution of their parent stars. Specifically, stellar X-ray and UV radiation can impact the chemical and physical properties of planetary atmospheres. While UV radiation is primarily absorbed
The Sun regularly exhibits magnetic phenomena, including sunspots and solar flares, which are not only visually appealing but also crucial for in-depth study and understanding. This is because these phenomena arise from large-scale interactions between the solar magnetic field and its plasma. Moreover, they provide valuable insights into the structure of the Sun and its atmosphere. Almost all other
