The First Portuguese CubeSat
What is ISTSat-1?
ISTSat-1 is a 1U CubeSat and will be the first Portuguese CubeSat to be launched into space!
It’s being developed by the ISTNanosat team which is made up of students and teachers from University of Lisbon’s Instituto Superior Técnico, working out of Técnico’s Taguspark campus.
ISTSat-1 is a nanosatellite being developed under ESA’s Fly Your Satellite! program. ISTSat-1 is scheduled to be launched in 2021.
ISTSat-1 without its Z+ solar panel exposing its Antenna Deployment Mechanism (ADM).
A mission to educate
ISTSat-1’s main goal is to provide students with an interesting and challenging experience in order too foster enthusiasm for space, science and technology.
Due to their smallness and relative simplicity, CubeSats are appropriate and, therefore, commonly used for this purpose. These satellites allow students a hands-on approach with a real and feasible space project, that extends to many fields of engineering.
ESA's Fly Your Satellite! program
Developing ISTSat-1 to be a CubeSat was an important decision since it allowed us to apply to ESA’s Fly Your Satellite! program. Being accepted to the program in March 2017 was a very important milestone for the team since it meant we could fulfill our most ambitious goal: Launch ISTSat-1 into space!
The Fly Your Satellite! program, now in its second edition, offers the student teams professional support throughout the process of creating and developing the satellites. ESA does this by giving students access to professional test facilities and offering financial support for the teams to be part of various workshops and training sessions. Since every team has access to all of these resources, all of them have to periodically show ESA the result of their continuous work and show their progress. The teams that last until the end of the program get to launch their satellites!
Even though all FYS participants have the same goal, to launch the developed satellite, they each get to decide their CubeSats’ mission…
What is ADS-B?
Automatic Dependent Surveillance-Broadcast, ADS-B for short, is an aircraft survaillance system designed to compliment the Primary Survaillance Radar (PSR) and, in a near future, replace the Secondary Surveillance Radar (SSR). Its main purpose, much like SSR, is to control aircrafts’ statuses, like velocity and altitude, around the world.
Why will it replace SSR?
It has many advantages! Firstly, messages are not encrypted and, therefore, available to everyone. Another advantage is that the aircraft information can be received without an interrogation signal, it’s always being broadcasted (nevertheless, interrogations are still possible). Additionally, the ADS-B system is built so that not only ground stations but also pilots have this information available in real-time.
What does it have that others don’t to accomplish world-wide coverage?
ADS-B was designed to have a space component. Thus, not only will aircrafts and ground stations broadcast and re-transmit ADS-B messages, but also satellites. This means that these will relay messages sent by aircrafts in order to cover areas which ground stations can’t reach, like oceans, deserts or mountains!
There are already satellites working to provide a space component to the ADS-B system. Aieron’s Iridium Constellation is made up of 66 Low-Earth Orbit (LEO) satellites which provide ADS-B worldwide coverage.
So what's the mission?
ISTSat-1’s purpose will be to carry out a feasibility study for the use of nanosatellites, namely CubeSats, to receive ADS-B signals in areas that are covered by terrestrial stations. Assuming the terrestrial stations are able to identify all spacecrafts within their reach, ISTSat-1’s collected ADS-B data will be compared to the terrestrial stations’. CubeSats are very simple and cheap when compared to the classical satellite, so our mission is to prove that even a “low-budget” satellite can accomplish the purpose of serving as an ADS-B support satellite.