Supernova remnants are clouds in rapid expansion produced by supernova explosions. They are often characterized by a complex morphology, resulting from the interaction between the expanding remnants and surrounding clouds. Supernova remnants also emit radiation on a wide band of the electromagnetic spectrum. This is due to the variety of phenomena occurring in these objects, and because of the different
Since astronomers captured the bright explosion of a star on February 24, 1987, researchers have been searching for the squashed stellar core that should have been left behind. A group of astronomers using data from NASA space missions and ground-based telescopes may have finally found it. [Continue reading at this link]
A “transit” occurs when we observe a planet moving across the disc of its star. Thus, during the transit the planet obscures a small portion of its star, slightly reducing its luminosity. While in the Solar System the only planets we can observe transiting in front of the Sun are Mercury and Venus, transits is still the most efficient method
The mechanisms involved in the formation of planets are still not completely understood. The most widely accepted model that describe the formation of gaseous planets is the core-accretion model. In this paradigm, the formation of these planets starts with the formation of a large rocky core by the coagulation of planetesimals, followed by the accretion of a large gaseous envelope
Supernova explosions, occurring and the end of the life of massive stars, are ruled by a complex physics, and they can not be described by a simple spherically symmetric geometry. The rarity of these events make even more difficult to understand the physical processes involved during the explosions. For instance, on average only one supernova explodes in our Galaxy every
Stars which are not fully radiative (e.g., less massive than 8 solar masses) produce a magnetic field in their interior whose intensity and topology depends on the type of star and internal structure. The magnetic field is then drag toward the surface and here it interacts with the plasma in the photosphere, chromosphere, and corona triggering phenomena classified as “magnetic
Solar corona is the outer atmosphere of our star. Extended for several solar radii, it is made of million degrees plasma, thus being hotter than the gas in the photosphere (about 5600 degrees). Several scientist have tried understanding the mechanism responsible for the heating of coronal plasma, but it is has been an open issue for decades. The most promising
To understand how planets form, it is mandatory to study the evolution of protoplanetary disks, e.g. disks of gas and dust grains orbiting around stars during the first 3-5 million years of their evolution, a that may evolve into planetary systems. In the last years, several observations have been done in order to detect the molecules, mainly organic, in these
Supernova remnants are nebulae created by supernova explosions. These expanding clouds are formed by the interstellar medium shocked and heated up by the expanding shock produced by the explosion, and the knots of material launched by the exploding star, called ejecta. These ejecta are located behind the expanding shock, traveling with lower velocity, and they are heated up by the reverse shock: