Download PDF Fall Issue of The Bridge on Space Exploration September 1, 2021 Volume 51 Issue 3 Close collaboration between engineering and science has enabled marvels of space exploration over decades. Eight exemplary missions are described in this issue, conveying the excitement, challenges, and breakthroughs involved in efforts to better understand the wonders and mysteries of this solar system. Guest Editor's Note Synergies in Engineering and Science for Space Exploration Thursday, September 16, 2021 Author: Steve Battel I hope you enjoy reading the articles in this issue of The Bridge as much as we have enjoyed putting them together for you. I have worked my entire career at the interface of engineering and science and have experienced the rewards that come from developing technology to enable scientific exploration. I’m very pleased that (with one exception) the space missions discussed here are ones that the authors and I have worked on together. There is truly a shared bond and a joy of accomplishment that comes from doing challenging work together, learning new things, and contributing as a team to the process of scientific discovery. Background If one considers the period between Tsiolkovsky (1898) and Goddard (1926) as the genesis of modern rocketry, then all of us are children of the rocket age. With the launch of Sputnik in 1957 we are also the parents and children of the space age. This exciting period of innovation and exploration is just a short blip in the long history of human science and engineering achievement, and yet it is a time of incredible partnerships filled with stunning and memorable accomplishments. The history of space science is a story of the synergies that arise from a push-pull cycle where engineering and enabling technologies open the door to new scientific capabilities and discoveries, and new and increasingly challenging science questions similarly drive engineering methods and technology advances. If done correctly in a collaborative framework, the results can be truly groundbreaking. In the early stages of the space age, however, the partnership was very different as engineers and scientists struggled to survive as much as prosper in what was a relatively unknown and untested space environment. Thus, science, although it prospered, was oftentimes a serendipitous passenger riding on the back of spaceflight technology as it was developed. The Air Force’s Discoverer (sometimes referred to as Corona) and NASA’s Pioneer, Surveyor, Explorers, and other programs were fundamentally driven as much by engineering as by science. Science missions from the 1970s, including Voyager and Viking, hold a special place in history, but NASA’s Great Observatories are generally considered the critical pivot point when achievements in space science came to their current prominence. The Hubble Space Telescope, in particular, is an iconic engineering masterpiece that continues to make extraordinary scientific contributions. Derived from National Reconnaissance Office technology and supported by human servicing for repairs and upgrades, it is arguably the greatest science machine in history. Together with the Cosmic Background Explorer, Living with a Star, and other missions in the same timeframe, Hubble began the exciting growth of NASA’s science program, with similar science growth in Europe, Russia, and other countries. In This Issue As guest editor, I have tried to construct an interesting and fun story, from the early space program to Hubble and then to many of the new and exciting current missions. My goal was to introduce you to a broad range of representative science missions, with each article written from both an engineering and a science perspective. I am particularly happy that each article tells a compelling personal story in its own unique style. While each article stands alone, the order is important because of the thematic thread of walking you through the why and how as much as the what. The story begins with the estimable Lou Lanzerotti offering his historical perspective as a witness to nearly everything that has happened in space exploration over the past 60 years. Lou has been a dear friend and a mentor to me and I am deeply grateful for his participation. The full-length articles begin with Hubble, followed by missions representing each of NASA’s science disciplines: Earth science and applications, heliophysics (i.e., solar and space physics), scientific exploration of the planets and other solar system bodies, and astronomy and astrophysics. The European Space Agency (ESA) has been a wonderful partner with NASA on most of the missions discussed here so I am thrilled to include its ambitious JUICE mission in this collection. We start with Hubble because I see it as the anchor of this issue’s theme of how engineers and scientists work together in space exploration. The Dragonfly mission is last because it is a new and innovative mission that shows the breadth of the engineering and science partnership. The order of the articles in between is intended to make your reading fun and interesting—you will be aboard a space roller coaster transporting you back and forth across the solar system and beyond. From the Hubble Space Telescope observing the distant universe from low Earth orbit, we land on Mars with the Curiosity rover, then jump to Jupiter with ESA’s JUICE mission, touch the Sun riding in cool comfort behind the heat shield of Parker Solar Probe, rendezvous with and take a sample of asteroid Bennu thanks to OSIRIS-REx, come back to observe the Earth using the MAIA observatory, observe the Big Bang using the James Webb Space Telescope, and finally head to Saturn’s moon Titan for a flight on the proposed Dragonfly rotorcraft. Before you buckle up for the tour, please stay with me here for a couple more things: First, I am deeply grateful to all these very busy and extraordinary authors for the time they have given to brainstorming and writing and rewriting these articles. You will see that they are truly expert innovators in both engineering and science as well as wonderful storytellers. Second, what you are reading is, as always, the product of great editing, thanks to Cameron Fletcher. I am indebted to her for her good humor and soft touch in guiding us to improve the product and to help you feel the fun, joy, and excitement of what we do. Each article was also evaluated for technical accuracy and I am thankful for the time given by each of the readers: Jason Barnes, Paul Geithner, Leonid Gurvits, Ken Hibbard, Barbara Hilton, Garth Illingworth, Jim Kinnison, Jean-Pierre Lebreton, Berrien Moore, Matt Mountain, Nour Raouafi, Massimo Stiavelli, Ashwin Vasavada, Rick Welch, and Cat Wolner. I hope you enjoy this issue and have as much fun cruising to each destination as I did in working with the authors and the Bridge team to put it together.  In 1898 Konstantin Tsiolkovsky developed the first scientifically viable proposals to explore outer space with rockets; in a ground-breaking 1903 paper he presented the “rocket equation” where a liquid rocket with changing mass is used to escape the Earth’s gravity. Robert Goddard successfully launched the first liquid-fueled rocket in 1926. About the Author:Steve Battel (NAE) is president of Battel Engineering, Inc. and adjunct clinical professor in the College of Engineering at the University of Michigan.