...While the National Space Council has laid out a clear path to a prosperous American future in space and NASA leadership have embraced ambitious goals with quick and efficient plans, H.R. 5666, the National Aeronautics Space Administration Authorization Act of 2020, would return American spaceflight beyond low Earth orbit to governmental control. It would dictate the destination — Mars...
by Jeff GreasonDecember 09, 20195 min read1 Comment
I use social media mostly to connect with a small group of friends, but I have noticed a rise, even among that group, of a certain form of magical thinking that I believe is misinforming our cultural view of the future and how we link our actions today to that future. That growing disquiet was triggered when I saw, in a discussion about recent policy debates, the phrase “We NEED renewable power, we NEED space colonization”.
"...there's got to be six good ways to turn massless power in to propulsion, how do you get the power? If we can get the power, we can get the thrust..."
Jeff Greason interview on the future of advanced propulsion at ISDC 2018.
The problem, well-known in the propulsion world, is that there’s more to the story – where does the power come from? The inside joke that “we could get to Mars easily if we only had a long extension cord” goes back to the Von Braun and Stuhlinger era of the 1950s. The ideal power for a rocket thruster (100% efficiency) is Power = 0.5 * Thrust * Isp.
...On the other hand, it is staggering that humans have been going in to space since 1961 (57 years as I write this), and we STILL KNOW ALMOST NOTHING about the effect of gravity on human health other than “zero is bad”. .....
NASA has awarded a $500,000 grant to the Tau Zero Foundation for a 3-year study titled "Interstellar Propulsion Review." Unlike prior studies, which were . . .
