Did you know that SpaceX used two microsatellites to test their broadband internet access? In case you didn’t, I’ll break everything down for you on how SpaceX used microsat 1A & 1B and microsat 2A & 2B.
MICROSAT 1A & 1B
The MicroSat 1a and 1b were two microsatellites to test technologies for SpaceX’s planned 4000-satellite Starlink constellation. They were kept in place to provide broadband internet access.
These satellites were the first of series of eight experimental demonstration spacecraft. They carry a Ku-band payload and validate the design of a broadband antenna communications platform that leads to the final low earth orbits (LEO) constellation design.
Additionally, the satellites carry a single low-resolution panchromatic video imager. The imager captures low-resolution images and video of Earth and the satellite itself.
Unlike the images collected by other satellites, the images taken by Micros were not to be used for commercial purposes. Instead, the images could have potentially been used for general educational purposes such as through the release of inspiring public Earth images.
SpaceX had planned to use three ground stations to test the satellites MicroSat 1a and 1b. One was to be located at SpaceX headquarters in Hawthorne, California, a second at SpaceX’s commercial satellite development center in Redmond, Washington, while the third was to be based at the Fremont, California, headquarters of Tesla Motors.
The satellites were to operate in near-polar orbits at an altitude of 625 kilometers circular orbits at approximately 86.4 degrees inclination for a minimum of six to twelve months.
Due to change of plans, and they were later used for ground-based tests. Eventually, the launches of Microsat 1A and 1B were canceled in favor of the next development step; the MicroSat 2A and 2B satellites. You can visit Getsat.com microsat systems to learn more.
MICROSAT 2A & 2B
Just like their predecessors, the MicroSat 2a and 2b are two similar satellites developed to test technologies for SpaceX’s planned 4425-satellite Starlink constellation to provide broadband Internet access.
These satellites were developed to replace the MicroSat 1A and 1B microsatellites as the first test satellites for the SpaceX constellation.
Both Microsat-2A and Microsat-2B are identical in their construction and operation.
The two similar satellites were called MicroSat-2a and MicroSat-2b during development and later renamed to Tintin A and Tintin B upon orbital deployment.
Both of these satellites were deployed to space in one mission aboard a SpaceX Falcon-9 v1.2 launch vehicle into an orbital plane of 514 km circular at 97.44 degrees inclination. After insertion, the satellite orbits were they were later to be raised to the desired mission altitude of 1125 km circular.
SpaceX plans to continue operation until the primary mission goals (global broadband internet) can no longer be met. At which point the spacecraft will be removed from its orbit. In the long-term, SpaceX has plans to develop and deploy a similar version of the satellite communication system that would be used on planet Mars.
The primary structure for the Microsat-2A and -2B test spacecraft is a box design measuring 1.1 m × 0.7 m × 0.7 m. It contains the spacecraft flight computer, power system components, attitude determination and control components, propulsion components, GPS receiver, and broadband, telemetry, command receivers, and transmitters.
The primary bus is mounted on the payload truss system, which also carries communications panels, inter-satellite optical link transmitters and receivers, star trackers, and a telemetry antenna.
There are two 16m² solar panels, measuring 8m by 2m. Each spacecraft has a total mass of about 400 kg.
The attitude of the spacecraft is 3-axis stabilized, and is dynamically controlled over each orbit to maintain attitude position for two pointing modes of operation: broadband antenna and solar array (solar arrays facing the sun for charging).
Power is supplied from the solar panels designed to deliver sufficient power at the predicted end of spacecraft life to not impair any of the functions. The Thermal Control System ensures that components in the spacecraft are kept within operational temperature ranges.
In addition to proving out the development of the satellite bus and related subsystems, the test program for the Microsat-2a and -2b spacecraft will also validate the design of a phased array broadband antenna communications platform (primary payload) that will be included in the final spacecraft design for the proposed NGSO constellation.
The Microsat-2a and -2b has communication paths utilizing five broadband array ground stations located in the western United States, together with three transportable ground stations that will be deployed near the fixed ground station locations, all within the contiguous United States (“CONUS”).
The primary Telemetry, Tracking, and Command (“TT&C”) ground station are located near the primary site in Redmond, WA to facilitate and control the broadband array testing. The testing will help to validate some design parameters.
Besides demonstrating the progress made in developing the satellite bus and other relevant subsystems, the test program for the Microsat-2a and -2b was to give legitimacy to the design of a phased array broadband antenna communications platform (primary payload). This design was included in the final proposed NGSO constellation spacecraft design.