The Terrascope

The Terrascope: Earth’s Atmosphere as a Telescopic Lens

Alpert, Shane (TU Delft Electrical Engineering, Mathematics and Computer Science)

Visser, P.M. (mentor)
Stam, D.M. (mentor)

Delft University of Technology

2020-08-31

This research contains the design, modeling, and analysis of the Terrascope. This apparatus intends to use the Earth’s atmosphere as a lens to bend light rays from celestial objects and focus them into a detector placed at a distance from the Earth, for example, the Moon. We develop an independent model from that of David Kipping, on whose Terrascope research this work is based. Our Terrascope model uses gradient-index optics to calculate the light bending through the Earth’s atmosphere. We also model three different atmospheric effects which modify the light passing through the atmosphere: turbulence, Rayleigh scattering, and ozone absorption. Our results show that turbulence has the largest impact on the light, and, consequently, on the functioning of our Terrascope. It causes the light to spread out, decreasing the image resolution and amplification. Without atmospheric effects, our model simulations predict a maximum amplification of about 55,000, the same results as Kipping. This occurs when using a 1m detector aperture, 1.5×10ዃm detector distance, and 1000nm wavelength light. Using the same parameters, when scattering and absorption are considered, the amplification decreases by 14%. When turbulence is considered, the amplification decreases by 99.98% to a total of 10. This is much lower than Kipping’s prediction of 22,500. We conclude that turbulence is the most important aspect of the Terrascope to consider in any future work. The Terrascope continues to be interesting concept for study and may have promise for observing celestial objects if a farther detector distance, longer light wavelength, and different atmosphere are considered.

http://resolver.tudelft.nl/uuid:74d6427b-8623-4cae-9030-c26e76853eb5

Student theses

master thesis

© 2020 Shane Alpert