White Paper

WHITE PAPER Rad-tolerant storage mrcy.com 2 INNOVATION AT THE SPEED OF MERCURY Today 's space imaging systems inform decision-makers in defense, intelligence and agriculture, while expanding scientific insight across a host of disciplines. Sensors continue to improve the resolution of their images with an exponentially increasing volume of pixels, providing more valuable details. At the same time, satellite designs are enabling very sophisticated imaging applications on smaller and smaller platforms. Landsat 1, launched in 1972, weighed 1,800 kg and was a hand-crafted device. Currently, constellations of imaging satellites are being launched with sizes as small as 100 kg, built using off-the-shelf components. These two factors — huge numbers of image pixels and very small orbiting platforms — are driving the demand for major improvements in future space-based data storage. Satellite designers need solutions that provide vastly more capacity while being smaller, lighter and able to operate reliably for years in a high-radiation environment. Mercury has accelerated the technologies of tomorrow with purpose-built innovation, creating a growing family of radiation-tolerant data storage subsystems. They combine rad-tolerant components with advanced error checking and correction (ECC), packaged in lightweight, standards-based, flexible form factors. This family of drives represents a long-term commitment by Mercury to support applications at the forefront of space technology. THE NEED FOR A LEAP IN RAD-TOLERANT STORAGE Going back to the days of Landsat 1, low earth orbit (LEO) satellites are the most useful and common platforms for space imaging. They deliver low-latency communications to Earth with a substantially better signal strength, when compared with geostationary orbit (GEO) satellites, at a relatively lower overall cost. Fast-moving LEO satellites make 12 to 16 circuits around Earth each day, meaning sensor data gathered over an area of interest must be stored on the satellite until it has line-of-sight communication with a system ground station and can download captured images. Various factors affect the data size of a stored satellite image; for example, is it color or monochromatic? However, the most significant factor is resolution, generally expressed in terms of the area size on the Earth's surface represented by a single image pixel. Thirty-five years ago, 60 m 2 per pixel represented a high-resolution satellite image. Today, that high- resolution parameter is 30 cm 2 , meaning an image of the same location on Earth is now incredibly more detailed but requires 40,000 times the amount of data storage. Imaging programs must somehow keep up. Deployment in space involves more challenges than just supplying vast amounts of storage capacity. Subsystems must be rugged, much like electronics in a weapons system, able to withstand the shock and vibration of a launch and then operate reliably in very cold temperatures for the life of the imaging mission, often as long as five years or longer. Our beautiful planet Earth, home to almost 8 billion humans, faces a complex set of problems that threaten all of us. From massive deforestation in remote regions to nuclear weapon development by despotic regimes, these threats must be understood in detail if we are to effectively resolve them. Imaging from space delivers many of those details, with increasing clarity every year. At Mercury, we are applying our experience and expertise to support advanced imaging missions with the latest space technologies and create a safer, more secure world.

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