Astronauts aboard the International Space Station (ISS) have taken delivery of two major new pieces of photonics-based hardware.
Launched on a SpaceX “Dragon” re-supply craft December 5, the latest science payload includes an upgrade for the Cold Atom Laboratory (CAL), which is based around laser-cooled atoms, and a new hyperspectral Earth imager. It docked with the ISS three days after launch.
The CAL upgrade includes equipment from the Colorado company ColdQuanta, which specializes in laser-based quantum technology kit.
Its “Quantum Core” system incorporates an atom interferometer - described by the company as an ultra-precise quantum sensor with uses ranging from fundamental research in general relativity and Earth science to future applications including GPS-free navigation.
Unique platform
Providing an upgrade on the existing CAL equipment, which arrived at the ISS last year and is based around Spectra-Physics tunable lasers, the ColdQuanta kit should enable the experiment to reach even lower temperatures.
ColdQuanta’s founder and CTO Dana Anderson describes the CAL as a unique platform for studying quantum phenomena and potential applications of real-time quantum sensor technologies.
He added: “Since it first arrived at the ISS in May 2018, the CAL has successfully demonstrated important milestones, including what [NASA’s] Jet Propulsion Laboratory called ‘the coolest experiment in the universe’ when a Bose-Einstein condensate was produced in orbit for the first time. We are excited to see what new milestones will be achieved with this second generation.”
According to NASA, the new package of kit will allow scientists to make subtle measurements of gravity. "This could enable scientists to probe fundamental theories of gravity and lead to the development of improved sensors that can be used for spacecraft navigation and to study Earth's climate," the agency said.
JPL itself describes CAL as a “compact, atom-chip based apparatus”, capable of trapping both rubidium and potassium atoms.
It explains: “The atom chip approach is chosen because of power and volume constraints, though for many applications, transfers the atoms into either a weak trap away from the chip, or into an optical lattice.”
Oil prospecting from space
Arriving alongside the CAL upgrade was the Hyperspectral Imager Suite (HISUI), a follow-up mission to the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) that flew on NASA’s Terra satellite.
Developed by the Japan Aerospace Exploration Agency (JAXA), the instrument is built around a reflector telescope and two spectrometers. Together, they will cover the visible and near-infrared range from 400 nm to 2.5 µm in 185 wavelength bands, and offer a ground resolution of approximately 25 meters.
According to NASA the main objectives of the HISUI mission are to discover prospective areas for oil and metal resource exploration, while it will also be used in a variety of environmental and agricultural applications.
“The most remarkable feature of HISUI is the high spectral resolution,” added the agency. “This allows for the contiguous measurement of reflectance spectra, which show the characteristics and physical properties of target materials across a wide wavelength range.”
