Exploring Other Earths: Astrobiology & Planetary Science

This short lecture introduces Professor Spergel, the basic outline of the course and its goals.

Discusses the structure of our Solar System, new dwarf planets, distance to nearest stars, and scales of our galaxy and visible universe.

Introduces approaches to defining life, basic building blocks of biochemistry, and potential ways of detecting life through byproducts like Methane.

Uses energy balance to determine effective temperature of planets, introduces temperature, black body spectrum, luminosity, and calculates the habitable zone.

Discusses how planet temperatures depend on albedo and atmospheric transparency, introduces global warming physics, and describes "Snowball Earth" episodes.

Introduces basic physics of gases, liquids, and solids, and describes how gas pressure and gravity shape planetary atmospheres.

Discusses properties of Mercury and Venus, including Mercury's ice poles and magnetic field, and Venus's atmosphere and runaway greenhouse effect.

Introduces basic properties of Mars, its atmosphere, seasons, and discusses Martian exploration, search for water and methane, and potential signatures of life.

Discusses Moon properties, crater physics, tidal interactions between Earth and Moon, and applies tidal physics to planets around M stars.

Discusses comets, asteroids, and moons of Jupiter and Saturn, their geology, atmospheres, and potential habitability.

Explains Kepler's Law, its relation to gravity, and how it's used to detect and characterize extrasolar planets.

Describes transit of Venus, its historical importance, and how NASA's Kepler mission uses transits to study extrasolar planetary systems.

Discusses General Relativity, light deflection, and microlensing observations for detecting planets, including orphan planets.

Discusses how mass and age determine star properties, methods for determining star distance and luminosity, and their relation to size and temperature.

Introduces stellar structure, nuclear fusion as energy source, and how nuclear burning drives stellar evolution.

Introduces Pauli exclusion principle and its application to material properties and atomic lines in planetary and stellar structures.

Introduces optics basics, explains how lenses and telescopes work, and discusses challenges of imaging planets around bright stars.

Discusses physics of star and planet formation, including conservation of angular momentum and the diversity of planetary systems.

Discusses building blocks of life, importance of water, amino acids, proteins, and the role of RNA and DNA in reproduction and protein synthesis.

Describes efforts to understand life's origin on Earth, synthesis of amino acids, and speculations about extraterrestrial origins of life.

Discusses basic principles of evolution, role of sex in evolution, and use of the Tree of Life to study life's origins.

Describes life forms that flourish in extreme environments and their implications for astrobiology.

Discusses mass extinctions in Earth's history, including the dinosaur extinction, and the current human-induced sixth extinction.

Discusses requirements for habitability, the faint Sun problem, range of potentially habitable planetary systems, and plans for using the James Webb Space Telescope to find signs of life.

Discusses the search for technologically advanced life, the Fermi Paradox, and contemplates the question "why aren't they here?"