My Ikigai

“Our Cosmic Address” is the quintessential Astro-lecture, recommended for everyone regardless of age, mood, or level of interest. In this session, we will journey from the Earth-Moon system to the Milky Way, the Virgo cluster of galaxies, and beyond: we will discover the Cosmic objects that surround us, those that contain us, and those toward which we are moving. The primary goal of this Astro-lecture is to understand where we are placed in the Universe through a realistic representation of Cosmic dimensions and distances.

Keywords: Earth, Moon, Solar System, Orion Arm, Milky Way, Galaxies, Virgo Cluster, Cosmic Superstructures, Laniakea.

From mathematical abstractions in the minds of a few humans, black holes have become protagonists in the history of our Universe. At the center of every galaxy lies a supermassive black hole, and the existence of both the galaxy and the central black hole appears to be intimately connected. Not everything that approaches a black hole is captured. In fact, much of the approaching matter is often swept away in the form of winds, relativistic jets, tsunamis. In this Astro-lecture, after donning “multi-frequency glasses”, we will travel to the vicinity of the event horizon of supermassive black holes at the centers of distant galaxies — first passing near the supermassive black hole at the center of our Milky Way Galaxy. We will discover that the Universe is far more imaginative than all of us humans put together.

Keywords: Black Holes, Galaxies, Event Horizon, Accretion Disk, Black Hole Winds, Relativistic Jets, Cosmic Feedback.

The Cosmos we live in isn’t exactly friendly: it’s in fact a very hostile environment for human bodies, and it can pose major threats to our planetary safety. In this Astro-lecture, we’ll discover together the space hazards that can affect life on planet Earth: from meteorites, cosmic rays, solar flares, massive stellar explosions, the merger of white dwarfs or neutron stars, and even the activation of the supermassive black hole at the center of our Galaxy. The primary goal of this Astro-lecture is to understand how precious Earth’s biosphere and all the life it supports are at a Cosmic level.

Keywords: Earth, Magnetic Field, Magnetosphere, Solar Flares, Aurora, Cosmic Rays, Supernovae, Compact Objects, Meteorites, Black Holes.

This is the story of how twelve hours of observation with the largest X-ray telescope ever built by humans serendipitously generated an entire field of scientific research, which inspired hundreds of minds across the planet to propose previously unimagined models, devise new strategies for gathering new observations, and build new telescopes. In this Astro-lecture, I will take you behind the scenes of the discovery of X-ray Quasi-Periodic Eruptions (QPEs), in which I had the privilege of participating, and the new frontiers of contemporary black hole astrophysics that this new cosmic phenomenon has opened up.

Keywords: Modern Astrophysics, Serendipity, X-ray Telescopes, Quasi-Periodic Eruptions, Black Holes, Tidal Disruption of Stars, Galaxies.

The X-ray Universe is not accessible from Earth because our atmosphere absorbs the X-rays arriving from the Cosmos: the history of X-ray astronomy is therefore inextricably linked to space science. In this Astro-lecture, I will share some details of the evolution of X-ray astronomy: from the first experiments conducted by Professor Riccardo Giacconi in the USA, to the realisation of the existence of galactic and extragalactic black holes, to the large satellites built by the major space agencies (ESA, NASA, JAXA) with their adventures and misadventures, to the satellites under construction and in development. Together, we will discover a myriad of high-energy Cosmic phenomena that decisively influence the formation and evolution of the Universe we live in; phenomena made accessible to human knowledge thanks to the strenuous cooperation of scientists and engineers from nearly every country in the world in the face of political, economical, and physical challenges and unforeseen circumstances. Space is a challenging environment.

Keywords: X-ray astronomy, the Energetic Universe, Plasma, Space Science, Black Holes, Space Telescopes, Active Galactic Nuclei, Space Catastrophes, X-ray Rainbows, Microcalorimeters.

Human physiology allows minimal access to the information contained in the Universe. In fact, unlike many other terrestrial animals, we can only perceive a tiny portion of the electromagnetic spectrum: what we call the “rainbow”. How does our view of the Universe change when technology allows us to expand our perception to frequencies other than that of the rainbow? In this Astro-lecture, we will discover this together, observing planets in the solar system, planetary nebulae, supernova remnants, galaxies and galaxy clusters, from the very low frequencies of radio waves to the very high frequencies of gamma rays, through infrared, ultraviolet, and X-rays.

Keywords: Rainbow, Radio Waves, Microwaves, X-rays, Infrared, Ultraviolet, Gamma Rays.

What is the history of humanity’s relationship with space? How does it affect the rest of planetary life? What happens to a satellite that stops working? In this Astro-lecture, we’ll journey through the history of the development of aerospace technology, from the first rockets used for X-ray astronomy, leftovers from World War II, to atmospheric balloons, to the first satellites and space stations. We’ll arrive at the present day, with an overview of the current state of nations with space agencies, the large number of scientific satellites in operation, their primary purposes, and their serendipitous scientific and technological discoveries; and the current state of commercial space operations and their impact on human scientific activity and the physiology of many terrestrial life forms.

Keywords: Space Science, Satellites, Space Stations, Space Telescopes, Light Pollution, Atmospheric and Stratospheric Pollution, Space Debris, Van Allen Belts, Serendipity, Dung Beetle, Tardigrade.

This Astro-lecture has a more mathematical, arithmetic, and geometric focus than the others; this doesn’t mean it isn’t part of our Universe. Starting from a story passed down for almost a millennium, as old as the game of chess, we’ll have a chat about exponential phenomena. We’ll discover how life, in the long run, is much more exponential than linear, especially in the case of very important phenomena. We’ll then move on to a real dilemma for the human mind — something we can’t dwell on for long without descending into physiological madness: the concept of infinity, and its various levels. With simple examples, we’ll touch on the first levels of higher infinity, to grasp what can be solidly and confidently grasped about this fascinating and dangerous concept. We’ll close our cosmic-mathematical chat with a light and meditative geometric-arithmetic digression. We will discover that behind simple mathematical operations (addition, multiplication, power) lie curious geometric relationships between the numbers 1 to 9.

Keywords: Chess and Grains of Rice, Exponential, Linear, Infinity, Higher-Order Infinites, Aleph, Georg Cantor, Arithmetic, Geometry.

What’s the life of an X-ray astronomer really like? In this Astro-lecture, I’ll share the educational and professional journey that led me to become an astronomer with three out of four petals of my personal Ikigai already in place, and actively fighting for the fourth. We’ll talk about unexpected journeys to distant lands, bureaucracy, meritocracy, great Professors, satellites breaking apart in orbit, and paths closing and opening like spirals. I’ve been observing the Universe for almost twenty years, and the Universe never ceases to amaze me.

Keywords: Astronomy, Astrophysics, Space Science, Italy, Spain, Netherlands, United States, Japan.