12-03, 17:00–17:20 (Europe/Luxembourg), Banquet Room
Solar sails have the potential to provide high ΔV for many types of near-term missions and are a stepping stone to laser driven lightsails that may one day take us to the stars. The 1653 m2 NASA Solar Cruiser solar sail propulsion system, made from 2.5 micron-thick thin film, recently advanced to NASA’s Technology Readiness Level (TRL) 6 through extensive testing (January 2024). The sailcraft platform has pointing control and attitude stability comparable to traditional platforms, supporting both in situ and imaging instruments. A sailcraft using the propulsion system will be capable of multiple km/sec ΔV per year, providing primary propulsion, navigation, station keeping, and inclination changing capability immediately applicable to near-term missions, and show scalability of sail technologies such as the boom, membrane, deployer, reflectivity control devices for roll momentum management to enable more demanding missions, such as high inclination solar imaging. The ~$30M project, managed by the NASA George C. Marshall Space Flight Center (MSFC), was funded by NASA’s Science Mission Directorate with the explicit goal of making the system available to scientists in upcoming flight mission proposals. Redwire integrated the solar sail system hardware, including the sail membrane from their subcontractor NeXolve, and the Triangular, Rollable and Collapsible (TRACTM) Boom, with NASA MSFC providing solar sail attitude, determination, and control system software and mission design. Redwire also built the active mass translator (AMT), which moves the sail relative to the bus to control momentum in the pitch/yaw directions. Potential enhancements to the system are also being developed, including the LISA (Lightweight Integrated Solar Arrays) which will be at TRL-7 after spaceflight demonstration in the summer of 2024 and Reflective Control Devices (RCDs), variable transmissivity thin films embedded into the sail and used for momentum management in support of system level attitude control systems.
Les Johnson is a physicist, award-winning science and science fiction author, and Chief Technologist at the NASA George C. Marshall Space Flight Center. His science fiction books include Crisis at Proxima (Baen 2024), The Ross 248 Project (Baen 2023), Saving Proxima (Baen 2021), Pluto: The Dark World (coming from Tor 2025), and more. Les’s popular science books include A Traveler’s Guide to the Stars (Princeton Press 2022) – now translated into 7 languages, Graphene: The Superstrong, Superthin, and Superversatile Material That Will Revolutionize the World (2018), Solar Sails: A Novel Approach to Interplanetary Travel, and others.
In his day job at NASA, Les served as the Principal Investigator for flight demonstrations of advanced space propulsion technologies including solar sails and electrodynamic tethers, and supported the development of nuclear thermal propulsion, electric propulsion systems, and more. Les is a member of the International Academy of Astronautics, the British Interplanetary Society, the Science Fiction and Fantasy Writers of America, and MENSA – and is the Program Chair of the Interstellar Research Group.
Les was a technical consultant for the movies Europa Report, Lost in Space, and Solis. NPR, CNN, Fox News, The Science Channel and The Discovery Channel have all interviewed Les about space and space exploration. He was the featured Interstellar Explorer in the January 2013 issue of National Geographic magazine and appeared there again in March 2019.