In December of 1988, NASA launched the $500-million Lacrosse satellite. Lacrosse's main attribute, like most spy satellites, is its image sensor. Lacrosse beams microwave energy to the ground and reads the weak return signals reflected into space. This allows the satellite to "see" objects on Earth that would otherwise be obscured by cloud cover and darkness. In order to send out these signals, however, Lacrosse has very high power needs. It meets these needs with very large solar panels, larger than would be found on most satellites its size. Lacrosse uses a rectangular antenna, 48 feet long and 12 feet wide, that is very different from the standard mechanical antenna. This antenna is covered by rows and columns of small transmitting and receiving elements that help Lacrosse pick up the faint return signals bouncing back from the Earth.

Lacrosse also uses Synthetic Aperture Radar (SAR) technology. This SAR technology allows Lacrosse to see objects only three feet across. That level of detail is necessary to identify military hardware. When doing imaging, instead of providing a constant stream of images like most radars, Lacrosse records a series of snapshots as it arcs over the Earth.

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Last updated on: 8 August 1997.