A vast galaxy cluster lurks in the centre of this image from the NASA/ESA Hubble Space Telescope. Like a submerged sea monster causing waves on the surface, this cosmic leviathan can be identified by the distortions in spacetime around it. The mass of the cluster has caused the images of background galaxies to be gravitationally lensed; the galaxy cluster has caused a sufficient curvature of spacetime to bend the path of light and cause background galaxies to appear distorted into streaks and arcs of light. A host of other galaxies can be seen surrounding the cluster, and a handful of foreground stars with tell-tale diffraction spikes are scattered throughout the image.This particular galaxy cluster is called eMACS J1823.1+7822, and lies almost nine billion light-years away in the constellation Draco. It is one of five exceptionally massive galaxy clusters explored by Hubble in the hopes of measuring the strengths of these gravitational lenses and providing insights into the distribution of dark matter in galaxy clusters. Strong gravitational lenses like eMACS J1823.1+7822 can help astronomers study distant galaxies by acting as vast natural telescopes which magnify objects that would otherwise be too faint or distant to resolve.
A vast galaxy cluster lurks in the centre of this image from the NASA/ESA Hubble Space Telescope. Like a submerged sea monster causing waves on the surface, this cosmic leviathan can be identified by the distortions in spacetime around it. The mass of the cluster has caused the images of background galaxies to be gravitationally lensed; the galaxy cluster has caused a sufficient curvature of spacetime to bend the path of light and cause background galaxies to appear distorted into streaks and arcs of light. A host of other galaxies can be seen surrounding the cluster, and a handful of foreground stars with tell-tale diffraction spikes are scattered throughout the image.This particular galaxy cluster is called eMACS J1823.1+7822, and lies almost nine billion light-years away in the constellation Draco. It is one of five exceptionally massive galaxy clusters explored by Hubble in the hopes of measuring the strengths of these gravitational lenses and providing insights into the distribution of dark matter in galaxy clusters. Strong gravitational lenses like eMACS J1823.1+7822 can help astronomers study distant galaxies by acting as vast natural telescopes which magnify objects that would otherwise be too faint or distant to resolve.

Cosmic Queries – Black Hole Time Cloak with Charles Liu

ESA/Hubble, CC BY 4.0, via Wikimedia Commons
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About This Episode

Are black holes places or objects? Neil deGrasse Tyson and cohosts Chuck Nice and Gary O’Reilly answer grab-bag questions about distorting spacetime, Olbers’ Paradox, singularities, the shape of the universe, and more with astrophysicist Charles Liu.

Could you create a cloak of black holes to make time cease for you? Learn about configurations of black holes, time dilation, and Einstein’s relativity. Would it take you until the end of time to reach the singularity of a black hole? What would you see if you fell into a black hole? Are we all just prisoners of the present? Plus, Neil divulges how you can hear his voice at a Beyoncé concert.

Can you transfer information using quantum entanglement? We break down how subspace gets used in Star Trek, what it means for gravity to distort spacetime, and how gravity can be used to deflect asteroids. Discover Olbers’ Paradox: why isn’t the entire night sky bright with starlight?

If Neil and Charles could time travel, where would they go? Could The Big Bang be a white hole? We talk about creating a Dyson swarm, using aerogel to insulate a journey into inner Earth, and the shape of the universe. Is the universe really flat?

Thanks to our Patrons Logan Kent, James in 3d, Renee Skrip, Maarten Spruijt, Alan Domonoske, Liam Predergast, sparkman, Cecil J Taylor, abhinav yadav, and Markus Gustafsson for supporting us this week.

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