AST 100: Our Cosmic History

A tour in space and time to find our place in the universe

Our Cosmic History is a natural science foundation course, open to all IUB students, especially those without a math background. The goal is to unravel the universe’s 14-billion-year saga and explore its seven ages, unveiling the engine powering its metamorphoses: a delicate dance of chance and necessity, leading to a cosmos teeming with complexity. This journey along the river of time is accompanied by the marvels of 21st-century astronomy and astrophysics.

The course is co-offered with PHY 100: Physics for the Next Generation popular among BBA students. AST 100 and PHY 100 are two codes for the same course. Here are the three main Learning Outcomes of the course:

  1. Understand our cosmic address by navigating the immensity of space and time.
  2. Identify the tools and methods used for uncovering the anthropocentric history of the universe.
  3. Realize the relevance of cosmic history in our life irrespective of our profession or culture.

Assessment Strategy

AssessmentMarks
Attendance10
Punctuality10
MCQ Quizzes (6 x 5)20
Midterm presentation21
Final presentation30
Group work9

Seven ages of the universe

The seven chapters of the course deal with the seven ages of the universe, respectively. Mirroring Shakespeare’s seven ages of a human life, Eris Chaisson divided the anthropocentric history of the universe into seven ages: particle, galactic, stellar, planetary, chemical, biological and cultural. Here I have compared these ages with the seven stages of the international Brahmaputra river metaphorically. Key events and topics covered in each chapter are as follows. [ya: years ago, M: million, B: billion]

  • Particle age: First 1 My

    Big bang, emergence of fundamental forces and elementary particles, domination of matter over radiation, rise of neutral atoms, cosmic background radiation; light and color, telescopes.

  • Galactic age: Until 11 Bya

    Dark ages, cosmic dawn, birth of galaxies, galaxy mergers, ionization of intergalactic hydrogen by the first stars, birth of the Milky Way; types of galaxies, active galaxies.

  • Stellar age: From 11 Bya

    Formation of Milky Way halo, population I stars, rise of star clusters and thin disk of our Galaxy, birth and evolution of stars, death of stars; planetary nebula, white dwarf, neutron star, black hole.

  • Planetary age: From 5 Bya

    Birth of the solar system, formation of the inner planets, cosmic bombardment, plate tectonics; gas giants, ice giants, moons, asteroids, comets, heliosphere, space weather, space exploration.

  • Chemical age: From 3.5 Bya

    Emergence of life on Earth, atmospheric oxygen and the ozone layer; detecting exoplanets, atmosphere of exoplanets, habitable zones, detectable signatures of life on exoplanets.

  • Biological age: From 1.5 Bya

    Emergence of complex cells, multicellular organisms, land animals, warm-blooded animals, extinction of the dinosaurs, origin of mammals and humans; probability of life out there.

  • Cultural age: Last 1 My

    Human migration out of Africa, Upper Paleolithic cultural revolution, beginning of agriculture and states, advancement of science and technology, waves of globalization, search for extraterrestrial intelligence.