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RapidEye Overview

Mission Background

RapidEye orbit
RapidEye (Image Credit: Geoimage)

The RapidEye business concept was initiated in 1996 by Kayser-Threde GmbH of Munich with support from the German Space Agency (DLR). The overall goal was to provide end-to-end solutions to clients whose geospatial information needs require large-area coverage, repetitive monitoring and frequent revisits.

The RapidEye constellation focused on agriculture and insurance markets. The RapidEye company was bought by the Canadian company Blackbridge in 2011 and sold to Planet in 2015.

 

Satellite Design

RapidEye layout
Illustration of the RapidEye spacecraft (image credit: SSTL, MDA, BlackBridge)

The MicroSat-150 satellite platforms were developed and built by SSTL (Surrey Satellite Technology Ltd.) based on the enhanced platform used for the TopSat and Beijing-1 remote sensing missions.

Each RapidEye spacecraft was three-axis stabilised, featuring a box-like shape. The overall design has the spacecraft divided into three separate functional volumes. At the base was the launch vehicle separation system along with some attitude sensors. In the mid-deck were the majority of the bus subsystems and the PEU (Payload Electronics Unit), while the optical imager and the star camera were located at the top end of the spacecraft.

Each of RapidEye's five satellites contained identical sensors, equally calibrated so that images are indistinguishable from each other. Together, the five satellites were capable of collecting over 6 million km² of 6.5 m resolution (resampled on the ortho product to 5 m), 5-band colour imagery every day. The system imaged a 77 km wide swath.

RapidEye Technical Specifications
Mass156 kg
Dimensions0.78 m x 0.93 m x 1.17 m
Design Lifetime7 years

 

Mission Operations

The RapidEye orbit was Sun-synchronous - all five satellites were evenly spaced in a single orbital plane. The altitude is 630 km, the inclination is 97.9° and the local equator crossing time is 11:00 hours (± 1 hour) on the descending node

The satellites followed each other in their orbital plane at about 19 minute intervals. The constellation approach in a single orbital plane permitted a cumulative swath to be built up (the spacecraft view adjacent regions of the ground, with image capture times separated by only a few minutes).

A revisit time of one day could be obtained anywhere in the world (±84° latitude) with body pointing techniques. The average coverage repeat period over mid-latitude regions (e.g., Europe and North America) was 5.5 days at nadir.

Learn more about RapidEye from this related website:

 
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