66702 - Principals of Astronomy

Course Unit Page

Academic Year 2022/2023

Learning outcomes

The aim of the course is to provide the fundamental and exhaustive
knowledge of the main aspects of astronomy and astrophysics, including very modern topics (e.g. extrasolar planets, black holes, dark
matter, dark energy). At the end of the course, the student will know
the main topics from positional astronomy to solar system, stars,
galaxies, and cosmology.

Course contents

- Basic spherical astronomy (solid angle, great circle, spherical triangles, shape and size of the Earth, Eratosthenes experiment)
- Terrestrial coordinates (latitude, longitude)
- Celestial coordinates
- Doppler effect
- Perturbation of coordinates (precessions, nutation, parallax,  proper motion, aberration)
- The motion of planets (including historical background)
- The Kepler laws
- The Earth (properties, seasons, tides)
- The Moon (properties, motion)
- Solar and lunar eclipses
- The Solar system (planets) and notions on Extrasolar planets

- The electromagnetic spectrum
- Astronomical observations (terrestrial atmosphere, astronomical sites, seeing, adaptive optics, ...) 
- Telescopes (reflection and refraction optics, submm-mm, radio, space telescopes, HST, Herschel, Planck, X-ray telescopes)
- Astronomical data (images, spectra)
- Radiation from astrophysical objects (luminosity, spectra, flux, 1/r^2 law)
- Apparent magnitudes and Pogson law, Color indices
- Extinction and atmospheric extinction
- Absolute magnitudes

- Black-body radiation, Planck, and Wien laws
- Relation between black-body and color indices
- Stefan-Boltzmann law

- Atoms and radiation (electronic transitions, hydrogen atom,  types of spectra, emission and absorption lines, continuum spectra, emission nebulae, 21 cm transition, basic thermodynamics) 

- The classification of stars and relation with black-body
- Types of stellar spectra and absorption lines, Luminosity classes 
- Hertzsprung-Russell diagram 
- Binary stars (visual, photometric, spectroscopic, astrometric)
- Mass of visual binary stars, The luminosity-mass relation

- The 4 equations of stellar structure
- Energy transfer mechanisms
- Energy ¨production¨ in stars and timescales
- Thermonuclear reactions, Proton-proton chain, CNO cycle, triple-alpha reaction

- Stellar evolution (HR diagram, time on main sequence, mass and internal structure
- Open and globular clusters, age estimate with HR diagrams
- evolution of low-mass stars, evolution of high-mass stars (Novae, Supernovae, Pulsars, Black Holes)

- Interstellar medium (gas phases, composition, types of nebulae, H II regions, molecules, dust, star formation, chemical enrichment)

- Our Galaxy (properties, structure, components, observations across the electromagnetic spectrum, stellar populations, spiral structure,  star formation, differential rotation, bulge, rotation curve, dark matter, central black hole, the local Group)

- Galaxies (Hubble classes, colors, spectra, Schechter function, luminosity functions, spirals, ellipticals, starbursts, merging, large scale structure, groups, clusters, galaxy formation)

- Supermassive black holes and active galaxies,

- Basic cosmology (Hubble law, age of the Universe, Big Bang, cosmic microwave background, large scale structure, density parameter, dark matter, dark energy, possible destiny of the Universe)


Main textbook: FundamentalAstronomy,Karttunen,H.;Kröger,P.;Oja,H.;Poutanen,M.;Donner,K.J.
5thed.,2007,XII,510p.449illus.,36incolor.. Springer-Verlag
The slides shown during the lectures will be made available.

Teaching methods

Oral lectures

Assessment methods

Oral exam, where the candidate should demonstrate to have an organic view of the discipline. The exam will start with a topic chosen by the student. The candidate should be able to deduce relations among physical quantities in a non mnemonic way as well as link the different topic of the course.

Teaching tools

Blackboard and presentations of powerpoint slides.

Office hours

See the website of Marcella Brusa