The Earthnet Programme: 40 years of evolution and future challenges
ESA's Earthnet Programme provided the initial means to access and exploit Earth Observation data.

blue arrow Mission Overview


The Project for On-Board Autonomy-1 (PROBA-1) was originally a technology demonstration mission of the European Space Agency, started in mid-1998 and funded within the frame of ESA's General Support Technology Programme.

Intended as a one-year mission, this small satellites - less than 1 cubic metre in size - has provided data since its launch on 22 October 2001 and is still operational today.


Orbit LEO Sun-synchronous
Orbital parameters 681x561 km
Swath Width 14km
Orbit Height 615km
Orbital plane inclination 97.9 degrees
Orbital period 96.97 minutes
Repeat cycle Approx. 7 days


PROBA-1 rolls in its orbit to take images: the satellite’s platform and payload work as one: spinning reaction wheels guided by a star tracker roll it up to 25º side to side and ±55º/±36º along its path. This helps PROBA-1 to compensate for its 7.5 km/s speed, like a photographer panning to snap a moving target. So each target can be seen on up to 5 different angles (-55º, -36º, nadir view, +36º and +55º).


blue arrow Mission Objectives

The objectives of PROBA-1 are:

  • in-orbit demonstration and evaluation of new hardware and software spacecraft technologies
  • in-orbit demonstration and evaluation of onboard operational autonomy
  • in-orbit trial and demonstration of Earth observation and space environment instruments

blue arrow Instruments

The Compact High Resolution Imaging Spectrometer (CHRIS) is the prime PROBA-1 instrument, used to explore the capabilities of imaging spectrometers on agile small satellite platforms.
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The High Resolution Camera (HRC) is a black and white camera with a miniaturised telescope, studying Earth, it also returns data on its own immediate environment.

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blue arrow Data

blue arrow DATA DOWNLOAD

Download CHRIS and HRC data from Proba-1 mission through the ESA TPM Online Dissemination system. The data is freely available to registered EO-SSO users.


ESA offers to registered user the access through the Online Dissemination server to the following data collections:

Details about how to request new CHRIS sites for new acquisitions are provided on Proba-1 information area at

blue arrow DATA TOOLS

A number of tools are available for visualising, processing and analysing PROBA-1 data.

Sentinel Application Platform

Sentinel Application Platform (SNAP) is a common architecture for all Sentinel Toolboxes. It is ideal for Earth Observation processing and analysis due to technological innovations.

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HDFclean V2 is a program for reprocessing images stored in the HDF file format (Hierarchical Data Format).


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Chris Toolbox

A Chris Toolbox development project is currently underway dedicated to the development of software modules for the BEAM toolbox enabling the exploitation of the high-resolution, multi-angular and hyper-spectral capabilities of the CHRIS instrument onboard the PROBA platform. A data reader for Chris data is already included in the BEAM v 4.0.

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