Antxon Alberdi: "With interferometry we can observe the most detailed detail of astronomical objects"
Antxon Alberdi: "With interferometry we can observe the most detailed detail of astronomical objects"
Astrophysics investigates the physics of the universe. At the Andalusian Institute of Astrophysics we investigate practically all fields of astrophysics: We carry out research close to the sun and the solar system, as well as research on distant galaxies, among others. In addition, we participated in several space missions. And, in some cases, observations are made in space to solve doubts about astrophysics.
I precisely work in the field of radio astronomy. "What is radioastronomy?" More than one may ask. All astronomical objects emit radiation and we, in the field of astrophysics, try to collect and interpret it physically. In radio astronomy we receive the radiation emitted by astronomical objects along the wavelengths of the radio waves.
Radioastronomy has the advantage of comparing with other branches of astrophysics: radioastronomy often allows to perform interferometric observations. When astronomers observe an astronomical object in any wavelength, in general we have two objectives. On the one hand, we seek the best possible sensitivity, that is, the detection of increasingly vulnerable objects. On the other hand, we seek the best resolution, that is, the ability to detect details. We should know the internal structure of the objects and know the smallest detail. All this with the help of interferometry.
Indeed. For example, if we look at the central nuclei of galaxies in the optical wavelength, only one set of eleven points is distinguished. As for radio astronomy, as I mentioned above, the main advantage is that we can take advantage of interferometry. What does this mean? By placing one telescope in San Sebastian and another in Los Angeles, we can observe the same astronomical object at a time and, in addition, we can build an incredible telescope, such as the distance between San Sebastian and Los Angeles. It would be approximately a telescope the size of the Earth's diameter.
Improves the size of a telescope resolution or the ability to detect details. That is to say, to greater telescope, better resolution. Therefore, we can take advantage of this advantage in the wavelengths of radio waves. With the help of several telescopes we can collect the signal or radiations simultaneously at different points of the earth's surface, combining them later and obtaining the effect of a telescope of spectacular dimensions (a telescope of 10,000 km of diameter). Thus, using interferometry in radio waves, the astronomical objects are collected in detail.
It is used in the research of eleven astronomical objects and, mainly, when high definition astronomical tools are needed. This high definition is the one that offers interferometry. For example, it can be used to know the central nucleus or the heart of galaxies. It is the central core where energy is generated. This zone is observed as a single point in other wavelengths other than radio waves. According to observations made with the help of interferometry, these objects have a nucleus and a group of particles in their structure. Its structure is similar to that which allows an aircraft.
We have also carried out studies of supernova with interferometry. The supernova has been known since ancient times, but if seen on a normal telescope, only small bright light spots are seen. As for radiointerferometry, a structure similar to that of a donut is observed. The first observations of this theoretical structure have been possible thanks to interferometry.
Several measurements made thanks to interferometry have shown that in the center of our galaxy there is an object. We have defined the size and mass of this object, and we have seen that it is less than the distance Earth-Sun, called astronomical unit. The mass, for its part, is four million times the mass of the Sun.
The nuclei of galaxies are the basic sources of energy. We believe that in the nucleus of galaxies there is an object with a huge mass, and we believe that this generates a huge amount of energy. This object of enormous mass is known as a black hole. Its mass is very large: It can be several million or a billion more than the mass of the Sun. This enormous mass suffers several gravitational processes and large amounts of energy are released. There is evidence that in the center of the Milky Way there is a black hole. This hole is called SgrA*.
No. There are galaxies in constant formation and creation of stars. These galaxies are called supernova factories or factories in common language (large mass stars explode at the end of their life cycle as supernovae). I am currently investigating this type of galaxies. We know that in galaxies there is a central nucleus with a hypothetical black hole. In this sense, we are investigating these supernova factories. We want to know the causes of the emission of energy that occurs in them. That is, we want to know if it is a consequence of the radiation that emits the black hole or if it is due to the formation of constant stars. With the help of interferometric techniques, we want to see how physical processes or others influence the behavior of galaxies.
Buletina
Bidali zure helbide elektronikoa eta jaso asteroko buletina zure sarrera-ontzian