Black Holes & Co.

This page features an overview of all our Spotlights dealing with black holes and other compact objects, notably neutron stars. Under the heading Close encounters with black holes, a Spotlight explores what an observer on a space-ship would see as, step by step, the ship approaches a black hole. The texts in the category How to track compact objects explores the phenomena that can be used by astronomers to track black holes and other compact objects in their telescopes, from their gravitational influence on neighbouring stars to the different ways that compact objects have of lighting up their immediate cosmic neighbourhood. The category The physics of black holes is dedicated to general theorems that have been proved about these objects. The category Physics in the background explores some physics that is useful for a better understanding of the Spotlights dealing with black holes and neutron stars.

Useful background information can be found in our introduction Elementary Einstein, especially in the chapter Black holes & Co..

Close encounters with black holes

	Descent into a black hole The story of an expedition coming closer and closer to a black hole - too close?

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How to track compact objects

More about the gravitational influence of black holes and neutron stars on their cosmic surroundings, from the orbits of nearby stars to accretion disks and the associated luminous phenomena.

	The dark heart of the Milky Way Information about the closest supermassive black hole - the central object of our own galaxy
	Luminous disks: How black holes light up their surroundings How the fact that black holes are very efficient in attracting surrounding matter leads to some of the most spectacularly luminous phenomena in the whole of the cosmos
	Active black holes: Ultra-hot cosmic beacons What astronomers can see once a black hole has heated up its cosmic neighbourhood, stimulating it to emit bright radiation

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The physics of black holes

	How many different kinds of black hole are there? Once they have settled down, there are actually only very few different kinds of black hole - find out which, and how black holes shed other distinguishing marks.
	Changing places How, in one sense, space and time switch their roles inside a black hole - and why this leads to a black hole's most characteristic property, namely that nothing can get out
	Particle accelerators as black hole factories?(also in the category Relativity and the quantum) The intriguing possibility that the next generation of particle accelerators might produce - and allow the detection of - miniature black holes

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Physics in the background

	What figure skaters, orbiting planets and neutron stars have in common Some information about what is called the conservation of angular momentum, and its consequences for neutron stars, black holes and the matter disks around them
	Heat that meets the eye (also under Cosmology) The connection between temperature and the emission of electromagnetic radiation, as well as the consequences for stars, matter disks around black holes, and cosmology

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