Acknowledgements Much of the material in this video is based on the - - PDF document

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Acknowledgements Much of the material in this video is based on the - - PDF document

Sep 11, 2022 296 likes •411 views

1 Acknowledgements Much of the material in this video is based on the excellent course An Introduction to Astronomy by Helen Johnson http://www.physics.usyd.edu.au/~helenj/IntroductiontoAstronomy.html Images and Videos courtesy of NASA,

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Acknowledgements

  • Much of the material in this video is based on the excellent course An Introduction

to Astronomy by Helen Johnson http://www.physics.usyd.edu.au/~helenj/IntroductiontoAstronomy.html

  • Images and Videos courtesy of NASA, ESA, and Wikimedia commons unless
  • therwise noted

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“Death” of Stars

  • Initial mass of ~0.6 Msun to 8 Msun

White Dwarf Black Dwarf

  • Initial mass of ~8 Msun to 25 Msun

Neutron Stars (Pulsars)

  • Initial mass > ~25 Msun

Black Holes

image courtesy of Nick Strobel at www.astronomynotes.com

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Black Holes

Escape Velocity

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Escape Velocity

  • Greater distance (R) means

lower escape velocity

  • Larger mass (of large object)

means higher escape velocity

  • Black hole is matter so dense that the escape velocity is greater than the

speed of light

  • Not even light can escape!
  • This occurs for everything within a certain distance of the singularity –

the Schwartzchild Radius

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How do we detect black holes?

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6 Supermassive black holes at the centers of galaxies

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Gravitational Lensing

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Now the first real image of a black hole, from the Event Horizon Telescope (EHT)

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