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Tungsten Black Hole Model

Tungsten Black Hole Model

50 total reviews

New Packaging

Item #089

If you compress any amount of mass, it becomes denser. If you compress it enough, it will become so dense that light can no longer escape it—this size is the object’s Schwarzschild radius. An object that is compressed smaller than this radius is a black hole.

This tungsten sphere has been engineered to have exactly the same radius as the Schwarzschild radius of Earth. If you compressed all of the mass of Earth into the volume of this tiny sphere, it would be so incredibly dense that you would not even be able to see it.

This sphere is a great aid for comprehending the scale of black holes and their extreme density. Made of tungsten, one of the densest elements in the universe, to help illustrate the high density of such an object. Also makes a great tungsten sample (W, 74) for element collectors.

Every object has a Schwarzschild radius proportional to its density: the Sun's is 3km, Jupiter’s is 2.62m, and a hamburger’s is smaller than a single atom. Karl Schwarzschild derived this property in 1915 using Einstein’s recent field equations.

Derivation (pdf) 

Radius: 8.87 mm
Weight: 53.34 g
Density: 18.5 g/cc



Our model was recently used as a visual aid in a lecture on black holes by renowned astrophysicist Brian Greene! (Featured around 22:54, but we recommend the whole lecture!)


Schwarzschild Radius Calculator

  • Detailed Info Included
  • Display Stand
  • Protective Storage Box

Regular price $40.00
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Customer Reviews

Based on 50 reviews
J.K. (Michigan, United States)
Great gift

The black hole model was of great quality. It was a wonderful gift for our son who loves Science. A fabulous conversation starter while being displayed on his desk. The Science lover will enjoy this one.

H.S. (Virginia, United States)

Great gift for our son who is very interested in Science.

B. (Victoria, Australia)
Looks great

Really cool little thing to have in my science classroom. My students thought it was really cool once I explained what it was

C.K. (Virginia, United States)

Cool little science gift. My year 11s liked it a lot


This was a bday gift for my bf who loves physics. He can't stop playing with it

F.B. (Virginia, United States)

Very fun and neat gift. Super cool and the stand and tungsten ball are very well made.


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