66702 - Principals of Astronomy

Learning outcomes

At the end of the course, students will be familiar with the measurements of the 'World', a word whose meaning has changed throughout history; they will also know the basics of gravitation and generation of stellar energy. Students will be able to assess the path to self-awareness of humans with respect to nature, and will have the skills required to understand the calculation of orbits, galaxy motions, stellar masses, the expansion of the universe, and the cosmic background.

Course contents

Space and time scales; order of magnitude estimate; shape of the Earth and dimensions of the Solar System; spherical astronomy; coordinate systems; measure of time and calendars; parallax; celestial mechanics and Kepler's laws; Virial theorem.

 

Light

Electromagnetic waves; electromagnetic spectrum; intensity, flux, luminosity; magnitudes; blackbody radiation; wave-particle duality; Bohr's model of the atom; emission and absorption lines; Doppler effect; telescopes.

 

Stars

Color and temperature; stellar spectra; H-R diagram; binary stars; stellar timescales; equations of stellar structure; radiative transport; nuclear reactions; stellar evolution; white dwarfs and neutron stars; variable stars and standard candles; formation of stars and planets; protoplanetary disks; exoplanets.

 

Galaxies

Interstellar medium: gas and dust; the Milky Way; the Great Debate; measure of distance to M31; the Hubble sequence; galaxy colors and spectra; measure of galaxy masses; dark matter.

 

Spacetime

Lorentz transformations; Minkowski spacetime; equivalence principle; Schwarzschild metric; gravitational lenses; black holes; gravitational waves.

 

Universe

Hubble's law; Olbers' paradox; cosmological principle; age of the universe; Friedmann equations; universe models; dark energy; Lambda-CDM model; cosmic microwave background; formation and evolution of galaxies; active galactic nuclei.

 

Readings/Bibliography

Fondamenti di Astronomia, di H. Karttunen, P. Kröger, H. Oja, M. Poutanen, K.J. Donner, a cura di A. Cimatti, P. Focardi, UTET Università, 2023.

For advanced material (in English): An Introduction to Modern Astrophysics, by Bradley W. Carroll, Dale A. Ostlie, second edition.

Teaching methods

Lectures.

Assessment methods

Oral exam. The exam will start with the student discussing a topic of their choice. The exam will assess the student's ability to derive relationships between physical quantities and to draw links between different topics explored in class.

Teaching tools

Blackboard and slides.

Office hours

See the website of Sirio Belli