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Very Short Introductions: Brilliant, Sharp, Inspiring
Almost everything we know about the Universe has come from studying the messages carried by light from outer space. Until only a handful of decades ago, this meant observing optical photons in the narrow visible region of the electromagnetic spectrum. However, recent technological developments have now enabled us to extend this range and explore the Universe at radio, infrared, ultraviolet, X-ray, and gamma-ray wavelengths. The observations reveal a plethora of exotic phenomena such as young galaxies at the edge of the visible Universe, quasars, pulsars, colliding galaxies, and exploding stars, often at great distances. We have discovered that the Universe is expanding and that the expansion itself is accelerating. Closer to our home planet, we track killer asteroids and comets. Working closely together, observational astronomy and astrophysics have shown us how stars produce their energy, where the chemical elements come from, how black holes form, and how the giant supermassive black holes lurking in the hearts of galaxies spew immensely powerful jets of particles and energy thousands of light years out into space.
And we now have new ways beyond light to probe the mysteries of the Universe. This Very Short Introduction describes how neutrinos and gravitational waves are revolutionizing our knowledge. How do we know all this? Advances in telescope technologies offer a partial explanation, but technology alone is not enough. Unlocking the secrets of the Universe also involves the critical application of the laws of physics to the observations. Cottrell describes how we are turning observations into knowledge and how theory, in turn, is inspiring new observations.
Preface
List of illustrations
The observable Universe
Big telescopes
Telescopes
The distances to the stars
Finding our place in the galaxy
The expanding Universe
New big telescopes
Big mirrors
Effects of the atmosphere
Atmospheric blurring
Recording images
The supermassive black hole in the centre of the Milky Way
Sky surveys
Robotic telescopes and the discovery of extrasolar planets
Two future optical telescopes
The radio Universe
Interferometers
Mapping the radio sky
Quasars
Supermassive black holes and their jets
Gravitational lensing
Pulsars
Another telescope with no moving parts
Probing the cold Universe
Very long baseline interferometry
The shadow of a black hole
The Square Kilometre Array
Telescopes in space
Optical and infrared space telescopes
The James Webb Space Telescope
Mapping stars
Gaia—surveyingtwo billion stars
Hunting for exoplanets
Ultraviolet observations
The X-rayUniverse
X-raytelescopes
Gamma-rayastronomy
The dynamic Universe
Supernovae
Tidal disruption events
Magnetars
Fast radio bursts
Near-Earthobjects
Chapter 6: Multi-messengerastronomy
Neutrino astronomy
Gravitational waves
The binary pulsar
Detecting gravitational waves
Gravitational wave observatories
Kilonova
A bigger picture
The cosmic microwave background radiation
Inflation
Dark matter
Dark energy
The standard model of cosmology
Further reading
Index
Galaxies: A Very Short Introduction