The Artemis II crewed lunar flyby mission is ready for takeoff, a ten-day journey carrying NASA astronauts on a free-return trajectory around the Moon and back to Earth. It is the first crewed mission of NASA’s Artemis program, which aims to land people on the Moon in 2028 and eventually establish a permanent base there. The stakes couldn’t be higher: it will be the first crewed mission beyond low Earth orbit since Apollo 17 in 1972 and will set several human spaceflight records.
But getting there is only half the mission. At an atmospheric reentry speed of approximately 25,000 miles per hour, the Orion spacecraft’s return to Earth will exceed all previous crewed reentry speeds in history. That scorching plunge through the atmosphere won’t be just an exciting finale, it will be one of the most scientifically critical moments of the entire flight, which is exactly where OKSI’s SCIFLI Airborne Multispectral Imager (SAMI) comes in.
SAMI will observe the ARTEMIS II reentry from NASA’s Gulfstream V (GV) aircraft. The mission is part of a multi-aircraft effort, where the GV and SAMI will be furthest up-range, focused on peak heating, followed by additional targeting in the later phases of the reentry, descent, and landing. The GV is outfitted with optical windows and a stabilized tracking system, collecting multi-spectral data spanning from the Visible through Mid-Wave Infrared (MWIR). This data will enable NASA to validate and improve the modeling tools needed to support future missions including, ultimately, landing spacecraft on Mars. Having observed the Artemis I launch, OSIRIS-REx sample capsule return, Solar Eclipse and SpaceX’s Starship, SAMI observes rare scientific phenomena, collecting novel scientific data by capturing the literal fiery and fleeting moments when a spacecraft meet Earth’s atmosphere at hypersonic speeds.
SAMI’s Capabilities
What makes SAMI uniquely suited for a mission like Artemis II is not just what it observes, but how it observes.
SAMI has a high-speed MWIR filter wheel, enabling the acquisition of time-resolved imagery across multiple narrow wavebands, which means it can track rapidly changing thermal and chemical conditions across the vehicle’s surface and wake as they evolve in real time during reentry. For the Artemis I mission, SAMI imagery through the plume provided direct evidence of plume-induced flow separation on the Space Launch System (SLS) base heat shield, data that could not have otherwise been obtained.
As mentioned, SAMI collects hyperspectral and multi-spectral data from the UV MWIR, allowing it to observe hundreds of wavelengths simultaneously and acquire spectrally, spatially, and temporally resolved data in a single pass. This is not a camera capturing a dramatic image for a National Geographic submission, it is a precision scientific instrument extracting quantitative physical data from one of the most extreme environments known to mankind.
Since those earlier missions, SAMI has only become more capable of novel scientific data collection. The addition of a UV-Visible imaging spectrometer has significantly enhanced its spectral range, broadening the physical phenomena it can characterize during an observation window that may last only seconds.
Why Reentry Observation Matters
Atmospheric reentry is where physics levels up. A spacecraft returning from lunar distance carries enormous kinetic energy that must be shed almost entirely through aerodynamic heating, which creates a plasma sheath around the vehicle, reaching temperatures comparable to the surface of the Sun. Engineers design heat shields to survive this environment, but computational models can only make an educated guess as to what really happens at those extremes. Ground testing cannot fully replicate the conditions of a real hypersonic reentry, and the spacecraft itself carries only limited onboard instrumentation.
Airborne observation platforms like SAMI fill that gap. By capturing spatially and spectrally resolved data from the outside of the vehicle during an actual reentry event, they provide ground truth that no simulation or laboratory test can match. This data directly feeds NASA’s efforts to validate and improve modeling tools for future missions. This data collect helps not just future Moon returns, but the far more demanding challenge of entering Mars, where the atmosphere is thinner, the margins tighter, and the consequences of model errors potentially catastrophic.
With Artemis II representing the highest-energy crewed reentry in over half a century, the data SAMI collects will be among the most valuable ever gathered on human spacecraft reentry dynamics. Every wavelength captured, every thermal gradient recorded, adds another layer of fidelity to the models that will one day bring astronauts home from Mars.
The Partnership Behind SAMI
None of this would be possible without the long-standing collaboration at the heart of SAMI’s story. OKSI’s partnership with NASA’s Scientifically Calibrated In-Flight Imagery (SCIFLI) team is behind the instrument’s development and deployment, a scientific collaboration built around a shared passion to capture data that matters most, in moments that are gone in seconds. SCIFLI provides operational and mission integration expertise; OKSI brings the sensor technology to make it possible. Together, they have turned SAMI into one of NASA’s most trusted airborne science assets, and with Artemis II, that partnership is gearing up for its most ambitious flight yet.
…but the story doesn’t end here.
Behind every data capture, every flight, every model validated, there is a team of relentless engineers, scientists, technicians, pilots and more preparing for it.
For the first time, cameras follow a SAMI mission from the ground up giving behind-the-scenes access to the people and the technology from first integration bolt to deployment.
Stay tuned for the mission behind the mission.