BayernSat

BayernSat takes pictures of the Earth and sends them to Artemis

BayernSat is a small satellite mission of the Institute of Astronautics of the Technische Universität München. The goal of the mission is to demonstrate new technologies, especially telepresence.

Rationale
In lower Earth orbits the communication windows are typically strongly limited. The ground station is only visible for a few minutes per overflight, and that occurs only a few times per day on average. Hence, the download of mission data has to take place in this short time slot. This however results in stringent requirements for the communication system (increased data rate) and the power subsystem (increased peak power usage). For missions that require extended communication windows or realtime data transmission, this is unacceptable. The solution is here the utilisation of geostationary satellites (as done by e.g. Spot 4, EnviSat). The advantage is that the com window can be extended from a few minutes to approximately half the orbit period (some 45 minutes) and more. In more than half of the cases the satellite can be reached immediately. When more than one geostationary satellite is used, the coverage can be - in principle - increased to 100%.

Telepresence
BayernSat goes even one step further. The communication windows are not only enlarged time wise, but are also to be utilised to enable telepresence in orbit. In astronautics, there are several applications for this. Stranded satellites can be repaired or fuelled. Docking manoeuvres can be simplified significantly; many applications can be undertaken - instead of by astronauts in space - from robot-controllers on the ground (and hence much cheaper). This however requires telepresence in orbit. Demonstrating the feasibility of this technology is the aim of BayernSat.

Further Technologies
Apart form telepresence, there are a couple of other technologies that are to prove their usability. There are for example the most efficient solar cells that have ever been flown on a satellite (Penta-Junction, 34% efficiency), on-board high performance computing using a silicon-on-insulator computer, and a parallel processor architecture (XPP), a high-resolution colour video camera, as well as a number of low-cost systems that will feature comparable performances at a much lower price.

Public Outreach
Even with its high-level technical challenge, BayernSat should not be appealing to just a small group of space experts. The aim is to demonstrate the above-mentioned technologies in a way that fascinates the broad public, namely by interactive live images of Planet Earth as it is "now". The BayernSat satellite shall, whenever illumination and com windows allow, transmit a live feed of Earth remote sensing data to the ground station at the Institute of Astronautics. But apart from that, this stream of images shall be put online in the Internet to be accessed by the public. The Bavarian TV broadcaster "Bayerischer Rundfunk" has offered to also show the live video feed in its telecast "SpaceNight". Furthermore, randomly selected Internet users shall be allowed to take control of the camera via their keyboard at home, and see the resulting changes within short time on the Internet / on TV. This approach aims at making BayernSat appealing to a broad public without losing the opportunity to undertake the needed technology tests. The ultimate goal is the development of a telepresence module, which allows other space missions to utilise telepresence.

The BayernSat Team at the Institute of Astronautics

The Satellite
BayernSat is basically a cube with a side length of little more than 40cm and a mass of 50kg. It can transmit data at least ten times faster than a computer modem. Furthermore, it is able to communicate with geostationary communication satellites as well as transmitters and receivers on the ground. The ground resolution of its video camera is better than 150 metres.

Short Description BayernSat