Burning clean

February 2020

Q: Tell us why the following is true or false: The Space Shuttle Main Engines and a hypothetical air-breathing hypersonic aircraft are both fueled by liquid hydrogen, so therefore their only emissions would be water vapor.

Draft a response of no more than 250 words and email it by midnight Feb. 12 to aeropuzzler@aiaa.org for a chance to have it published in the March issue.

COSMIC MYSTERY: I’m leftover from the beginning of time; I have spots; a spacecraft was launched to look for my spots and take my temperature. What am I? Your responses were reviewed by John Mather, who shared the 2006 Nobel Prize in Physics with fellow astrophysicist George Smoot for their work with NASA’s Cosmic Background Explorer spacecraft.

WINNER: You are the remnant radiative energy from the time our universe began! Cosmic Background Radiation (CMB), as you are called, represents the thermal energy left over from this “Big Bang!” We can’t see you with our human eyes, you’re way too cold at 2.725 Kelvin…so we use microwave detectors to capture you and your spots! We first became aware of you as “noise,” blaming pigeons’ droppings of all things! But our Penzias & Wilson & team soon found your ever-presence, garnering a Nobel Prize for their astounding and serendipitous discovery! Decades later, the Cosmic Background Explorer (COBE) mapped you in the sky, followed years later by the Wilkinson Microwave Anisotropy Probe, with many surprises in store (lumpiness, asymmetry, & gravitational waves, oh my)! Now with a telescope named after Planck, we have found your fluctuations that hint at dark matter and energy hiding an astonishing 95% of our universe! COBE’s very first “baby universe” picture of you used a trio of instruments: “a Diffuse Infrared Background Experiment (DIRBE) to search for your cosmic infrared background radiation, a Differential Microwave Radiometer (DMR) to map this cosmic radiation sensitively, and a Far Infrared Absolute Spectrophotometer (FIRAS) to compare the spectrum of the cosmic microwave background radiation with a precise blackbody.” We can’t wait to find what you’ll reveal to us in the decades to come!!!

José Camberos, Dayton, Ohio
AIAA associate fellow, Dayton-Cincinnati section
Team lead for design of aerospace systems for hypersonics
at the U.S. Air Force Research Lab
jose.camberos@us.af.mil