This week we’re talking about space launch. 2026 marks the 100th anniversary of liquid-fueled rockets, when Dr. Robert Goddard successfully pioneered the first launch from his aunt’s farm in Auburn, MA. Like the Wright Brothers before him, Goddard’s breakthrough opened the door to a new domain and the exploration, operations, and economic development that have evolved ever since. Mitchell Institute experts and John Reed, the Chief Rocket Scientist at United Launch Alliance, discuss this milestone event, launch advancements over the past 100 years, the future of this technology, and why it all matters.

Note regarding ISP:

Isp or “Specific Impulse”, as we talked about, is a measure of a rocket efficiency. It is calculated as the Thrust force divided by the product of the mass flowrate of propellants times the gravitational acceleration in a 1 g field – (F/(mdot * g0). If we think about force in Newtons second law, with F=ma, we can see that we have mass divided by flowrate (or mass/sec) and acceleration divided by acceleration. These units resolve to what we term seconds of impulse. As we discussed, the acceleration of the fuel is a function of the exhaust velocity of the combustion products. This efficiency is driven by the combustion chamber design and chemical process as well as the nozzle design. These elements were all developed for rockets by Robert Goddard in his laboratory and field demonstrations.