Relativistic Rocket Paper Written by Actual Astronaut!

When working on our latest research project which involved solving relativistic mechanics problems, we were surprised to find out that we'd been scooped on our relativistic rocket problem example by seven year. It was very cool, though, to find out that not only was the article that scooped us excellent, but that the author was in fact astronaut physicist Ulrich Walter!

You can read more about him at Wikipedia:
http://en.wikipedia.org/wiki/Ulrich_Walter

and on his university web page:
http://web.lrt.mw.tum.de/index.php?id=119

His relativistic rocket article is behind a paywall, but if you're at a university library, the link is
http://www.sciencedirect.com/science/article/pii/S0094576506001433

References
1. Walter U. (2006). Relativistic rocket and space flight, Acta Astronautica, 59 (6) 453-461. DOI: 10.1016/j.actaastro.2006.03.007

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