The Institute of Radio Astronomy (IRA), whose role is recognized at the international level, is the academic institution where radio astronomy research is traditionally carried out in Italy. We had the pleasure to speak with its director, Luigina Feretti.
What are the main projects currently active at IRA?
Our scientific research regards all the fundamental questions of modern astrophysics: for example, the dark matter, the galactic nuclei hosting supermassive black holes and the formation of all the cosmic structures. Our astronomy is “invisible”, but it is complementary to the optic one. There are several natural phenomena of non-thermal origin, generally due to relativistic particles that move in a magnetic field, which are detectable only through radio waves. We also carry out important studies of geodesy, for example by measuring the movement of the Earth's crust.
How many people are involved in your research activities?
Our headquarters are in Bologna. We manage the Italian radio telescope facilities: the "Northern Cross Radiotelescope", located in Medicina (Emilia-Romagna), and two 32-m single dish antennas located in Medicina and Noto (Sicily). Recently, a new 64-m antenna, the Sardinia Radio Telescope (SRT), started its preliminary operations near Cagliari. The total number of employees is in the order of 70: about half of them are researchers and engineers. The others are technicians and people of the administrative staff. We also have several associate scientists, including University professors, and young PhD students and post-doc fellows.
Your radio telescopes are part of a global network. From this point of view, what is the role of Italy?
Our antennas are part of the VLBI (Very Long Baseline Interferometry) astronomical and geodetic networks for about 150 days a year. Our radio telescopes serve in the European network as well as in the global one and work in synchrony according to the VLBI technique, in order to simulate a radio telescope as large as our planet. Thus, they offer a very great detail since the spatial resolution depends on the size of the total radio telescope. Furthermore, since there is a Russian radio telescope in orbit, called Spektr-R or RadioAstron, we can also simulate a radio telescope even larger than the Earth itself. In particular, as regards Italy, we decided to participate from the beginning to the global network because we understood the importance of this kind of cooperation. In fact, the Sardinia Radio Telescope will integrate the network of radio telescopes; this will lead to a greater collection area that will allow to see the fainter radio sources.
Recently, NASA has produced a study on the problems that might arise in the communication between humans and extra-terrestrial life forms. With regard to non-experts, the program Search for Extra-Terrestrial Intelligence (SETI) is probably the best known.
In general, you do not need an extreme angular resolution to search for extra-terrestrial intelligence. In the past, we made a passive-type search using a versatile tool, which is connected to the antenna and autonomously analyzes the signal while the antenna is observing a scientific target, such as a black hole or a galaxy. This signal is recorded and then analyzed with some special techniques. Since we know how natural signals are, we could find some extra-terrestrial ones because they are expected to be very strong and with a precise frequency. Thanks to the recent discovery of many extrasolar planets, we could switch from passive search to an active project in order to analyze those in a precise and promising position, but this research will be very expensive in terms of time and resources.