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Small Satellites Redefine Earth Observation

The problem: we rely on aging satellites to provide us with essential data.
NigeriaSat-2 image of Salt Lake City Airport, USA at 2.5m resolution. Credit/Copyright: NASRDA 2011
We rely on satellites for information about our planet to use for weather prediction, disaster management and for monitoring our forests, cities, agricultural land, and oceans. The problem is that large polar-orbiting satellites, such as those used in 2012 to predict and track the path of Hurricane Sandy and provide essential information for on-the-ground emergency and disaster management, have either reached or are approaching end of life. As a result, we are faced with data gaps until replacements are launched.

Current large-scale missions such as the 2,100 kg Suomi National Polar-orbiting Partnership and the 1,500 kg Landsat Data Continuity Mission (LDCM) must fulfill our nation’s heavy reliance on data until replacements such as the JPSS spacecraft are launched in 2017 and 2022. However, program complexities and funding issues threaten to cause delays to these missions.

Small satellites, such as Surrey’s 100 kg-, 150 kg-, and 300 kg-class spacecraft can provide a rapid, lower cost solution, performing a “gap-filling” interim data provision function or operating as a constellation of complementary or disaggregated sensors, as full replacements for these more expensive missions.

Small satellites—meeting end users’ operational objectives

Small satellites are the preferred platform for innovative commercial and scientific missions. Their proven utility, driven by a multitude of technological innovations, has enabled them to be used for essential government and institutional missions and to provide data that underpins commercial services and actionable information. The RapidEye 5-satellite constellation, built by Surrey and based on our 100 kg-class satellite platform, provides large-area, multispectral images in 5 m resolution. The RapidEye constellation has acquired over 3 billion square kilometers of imagery since 2009 for a wide range of commercial applications such as forestry, agriculture and environmental monitoring, and security and emergency management.

The 5 satellite Rapideye constellation was built by Surrey under contract to MDA

Quick timeframes and low costs to make missions happen

The Surrey approach is to carefully assess and focus our satellite solutions on meeting our customers’ primary mission-driving requirements. Eliminating over-complex requirements and cost-drivers allows us to build small satellites more quickly and to often complete delivery programs in 24 months or less from kickoff to launch readiness. Rapid program timeframes and lower costs are important enablers for government missions to get the “go-ahead” and enable commercial customers to close their business cases early.

High capability and rapid responsiveness

Many of the satellites that we depend on are based on outdated technology. Landsat 5, for example, while providing an incredibly long and invaluable service, is employing technology that was new in 1984.  Exploiting the benefits of quick-build small satellites means that we can continue to maintain or incrementally improve the quality and quantity of data products to end users with the latest technology by making discrete additions to an existing in-orbit system. For example, Surrey’s DMC constellation has been providing Landsat-comparable data since 2004, but has been improved with the launch of each new satellite. The latest addition, NigeriaSat-2, added a 2.5 m high-resolution service and stereoscopic pairs to the constellation’s offering.


Furthermore, while a Landsat satellite is only able to image a certain point every 16 days, constellations of small Earth observation satellites can provide better coverage. They can provide rapid revisit capabilities and greater responsiveness. If one satellite is unable to capture an image of a certain area due to cloud cover, the next satellite passing over can be tasked to capture the required image. Both the DMC and RapidEye constellations offer daily revisit imagery of a certain point.

Surrey is currently developing the technology for an “always on” single satellite system that will image the entire world’s landmass every 5 days. In a constellation of three or more, these satellites could image the entire world every day, providing vast coverage and an unparalleled ability to monitor change.


08 March 20130 Comments1 Comment

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