---
title: "New Topic"
id: "new-topic-2"
project: "Deep Space Exploration Project Publication2"
url: "https://hedronlabs.clickhelp.co/articles/deep-space-exploration-project-publication2/new-topic-2"
updated: 2023-08-24T16:48:36Z
---

# New Topic

#  Black hole
 
A black hole is a region of [spacetime](https://en.wikipedia.org/wiki/Spacetime) where [gravity](https://en.wikipedia.org/wiki/Gravity) is so strong that nothing, including [light](https://en.wikipedia.org/wiki/Light) or other [electromagnetic waves](https://en.wikipedia.org/wiki/Electromagnetic_radiation), has enough energy to escape its [event horizon](https://en.wikipedia.org/wiki/Event_horizon). The theory of [general relativity](https://en.wikipedia.org/wiki/General_relativity) predicts that a sufficiently compact [mass](https://en.wikipedia.org/wiki/Mass) can deform spacetime to form a black hole. The [boundary](https://en.wikipedia.org/wiki/Boundary_%28topology%29) of no escape is called the [event horizon](https://en.wikipedia.org/wiki/Event_horizon). Although it has a great effect on the fate and circumstances of an object crossing it, it has no locally detectable features according to general relativity. In many ways, a black hole acts like an ideal [black body](https://en.wikipedia.org/wiki/Black_body), as it reflects no light. Moreover, [quantum field theory in curved spacetime](https://en.wikipedia.org/wiki/Quantum_field_theory_in_curved_spacetime) predicts that event horizons emit [Hawking radiation](https://en.wikipedia.org/wiki/Hawking_radiation), with [the same spectrum](https://en.wikipedia.org/wiki/Thermal_radiation) as a black body of a [temperature](https://en.wikipedia.org/wiki/Temperature) inversely proportional to its mass. This temperature is of the order of billionths of a [kelvin](https://en.wikipedia.org/wiki/Kelvin) for [stellar black holes](https://en.wikipedia.org/wiki/Stellar_black_hole), making it essentially impossible to observe directly.

[![](/resources/Storage/deep-space-exploration-project-publication2/Imported/black-hole/img0001.png)](https://en.wikipedia.org/wiki/Stellar_black_hole)

Objects whose [gravitational fields](https://en.wikipedia.org/wiki/Gravitational_field) are too strong for light to escape were first considered in the 18th century by [John Michell](https://en.wikipedia.org/wiki/John_Michell) and [Pierre-Simon Laplace](https://en.wikipedia.org/wiki/Pierre-Simon_Laplace). In 1916, Karl Schwarzs[child](https://en.wikipedia.org/wiki/Karl_Schwarzschild) found the first modern solution of general relativity that would characterize a black hole. [David Finkelstein](https://en.wikipedia.org/wiki/David_Finkelstein), in 1958, first published the interpretation of "black hole" as a region of space from which nothing can escape. Black holes were long considered a mathematical curiosity; it was not until the 1960s that theoretical work showed they were a generic prediction of general relativity. The discovery of [neutron stars](https://en.wikipedia.org/wiki/Neutron_star) by [Jocelyn Bell Burnell](https://en.wikipedia.org/wiki/Jocelyn_Bell_Burnell) in 1967 sparked interest in [gravitationally collapsed](https://en.wikipedia.org/wiki/Gravitational_collapse) compact objects as a possible astrophysical reality. The first black hole known was [Cygnus X-1](https://en.wikipedia.org/wiki/Cygnus_X-1), identified by several researchers independently in 1971.