Earth Detector

At the altitude of a LEO orbit the satellite is close to the Earth and would require sensors with an extremely wide field of view to sense the leading and trailing edges of the Earth. For instance at GEO the field of view would be on the order of 30 degrees where at LEO it could be more than 160 degrees.  Therefore ADACS systems typically use Earth Detectors to sense the presents of the Earth as a course indication of pointing and are located on the face of the satellite that will be Earth pointed. One exception to this is when they are used on spin stabilized satellites and are mounted so they sweep across the Earth.

18 volt Solar Panel

18 volt solar panel 3D Model can be edited or animated.

Pocket Compass 3D model

Compass with hinged top and the needle is set to look at an object that can be moved for animation.

Solar array and antenna deployments

LEO satellites have a series of separation switches that close after it is released from the launch vehicle and they are used to start the flight computer. When the computer starts it checks the status of the switches and is programed to trigger on board timers that automatically actuate deployment mechanisms to release the solar arrays and antennas. These satellites have a 90 minute orbit period and therefore rely heavily on automated sequences to preform critical functions in a timely manor.

This provides a visual representation if this sequence on an OrbComm type satellite made by OSC. When released the arrays move from a stowed position into their on flight position. Then the communications antenna unfolds and locks into position to allow communications to be established with the satellite.

Once the deployments have been successfully completed the Attitude Determination and Control System (ADCS) will use sensors and GPS information to keep the antenna pointed at the earth.

OrbCom Sat

Based on OrbComm satellite made by OSC.


Space Flight Test satellite used to qualify hardware based in CTA satellite.


3D model based on NASA Acrimsat LEO satellite made by OSC

GEO Star 1A

3D model based on GEO satellite made by CTA

GEO Star 1B

3D model based on GEO satellite made by CTA

GEO Star 1C

3D model based on GEO satellite made by CTA

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Shining light on satellites and how they operate. Drawing from over 30 years of knowledge and experience in all phases of the life of a satellite from concept, to operations, and through end of life. You will find short topics intended to give you an understanding of how they work, the general concepts, and principals used along with information on ground systems. There is also a section dedicated to topics that can be used as basic concept training along with links to animations and 3D models I have created.