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Studenterkollokvium, Martin Weigand

A Caplan thruster: A hypothetical stellar engine that could move the Sun
A Caplan thruster: A hypothetical stellar engine that could move the Sun

Oplysninger om arrangementet


Mandag 11. oktober 2021,  kl. 14:15 - 15:00


Fys. Aud.

Supervisor: Frank Grundahl 

Title: Stellar engines – Moving the Solar System 

In 1964, astrophysicist N. Kardashev categorized civilizations into types based on the amount of energy it can control. A Type I, II, and III can use and store all the energy available on a planet, star, and galaxy, respectively. The human civilization has not reached Type I status yet. However, that does not stop us from discussing how we would progress if we reached Type I status. How would we become a Type II civilization with control over the energy of the Sun? Is it even possible? And if yes, what do we even need all that energy for?

In this colloquium, I will answer these questions by introducing stellar engines: hypothetical megastructures which use a star’s radiation to create usable energy. We will see that some proposed stellar engine models would enable us to use the energy from the Sun to move the Solar System. An analysis of these models’ efficiency, limitations and feasibility will be presented. Finally, I will show estimates of how far we would be able to move the Solar System over some time scale taking into account the galactic gravitational potential.