The ‘INSPIRE-2’ satellite is a product of a research and capability-building partnership between three Australian universities (University of Sydney, UNSW, ANU), and is a participant in a global small satellite research program (‘QB50’) managed by the Von Karman Institute in Belgium.
The QB50 program involves coordinated launch of fifty CubeSats from the International Space Station (ISS), scheduled for May 2017. The program will undertake three integrated space research studies, supplemented by additional research investigations by individual CubeSat teams. QB50 member satellites are scheduled for uploading to the ISS by the commercial space services provider OrbitalATK, under contract with the NanoRacks LLC service provider, by whom they will subsequently be launched.
The QB50 launch will be the first launch of Australian built and operated CubeSat spacecraft. Given international recognition that this form of spacecraft will increasingly be used for future Earth observation, navigation and communication roles, this activity offers a significant national capability-building benefit in the sector, as well as the opportunity to demonstrate utility and space qualification of proprietary instrumentation for several research applications. It is also closely aligned with a University of Sydney-led multi-party bid to establish an ARC Industrial Transformation Research Program Training Centre, which is currently under assessment.
Two other satellites (AU01: University of Adelaide and University of South Australia, and AU02: UNSW) are also part of the QB50 program. While information in this document relates specifically to the INSPIRE-2 spacecraft, much of its content is also relevant to the AU01 and AU02 projects.
Spacecraft and Mission – Summary
|Reference number||AU03 ‘INSPIRE-2’|
|Size||20cm x 10cm x 10cm; 2 Unit CubeSat format|
|Mass||2000 gm (2 kg)|
|Equipment||Commercial ‘off-the-shelf’ control and operating systems; 5 research instruments|
|Mission purpose||Scientific research and national capacity building|
|Altitude at launch||380km|
|Mission duration||8 - 12 months|
|Mission conclusion||Complete burn-up in upper atmosphere at >80km altitude|
Construction, upload and launch into orbit
The INSPIRE-2 craft is a two-unit (2U) cubesat. The craft uses commercial ‘off-the-shelf’ componentry for basic structural purposes and control functions, and carries a payload of five research instruments (CubeSat Design Overview Report for INSPIRE-2). One of the instruments (the Langmuir Probe) is supplied by the VKI for integrated program research purposes; the other four instruments are proprietary devices developed by the University of Sydney (USyd) and UNSW. The craft does not carry any substances/ materials of a flammable, corrosive or otherwise hazardous nature.
The craft will be assembled in the Faculty of Science (USyd) and Faculty of Electrical Engineering (UNSW), and validated for space capability at the Mount Stromlo facilities of ANU. INSPIRE-2 will then be consigned to the VKI, from where it will enter the packaging/ transport chain. Most notably, it will be packed by NanoRacks into the CubeSat Deployer apparatus, NanoRacks’ proprietary system “that mechanically and electrically isolates cubesats from the ISS, cargo resupply vehicles, and ISS crew” (NanoRacks CubeSat Deployer (NRCSD) Interface Control Document. NanoRacks LLC.). The craft will be uploaded by OrbitalATK to the ISS in this configuration as part of a NASA-contracted resupply mission, and subsequently launched by NanoRacks from the ISS at an altitude of about 380 km.
After launch into circular low Earth orbit the payload instruments will commence operation and data capture and storage, with data downloads being made to groundstations in Sydney, ANU ('Blue Wren' Groudstation) and Strasbourg, France. Communication access through these locations will occur an estimated 4 and 6 times per day, respectively, with total daily access durations of 21.6 and 28.6 minutes.
Mission conclusion and craft demise
At an estimated 8 to 12 months post-launch, orbital decay due to friction with air molecules will pull INPSIRE-2 into the upper reaches of Earth atmosphere. This friction will slow, melt, fragment and degrade the craft to a non-operational state. Detailed modelling (Fritsche, B. 2015. Uncertainty quantification for re-rentry survivability prediction. From ‘Space Safety is No Accident’. Sgobba, T & Rongier, I., Eds. Springer, 640pp.) shows that the craft will completely burn up in the atmosphere at an altitude above 80km, and that no debris will reach the surface of the Earth. This assessment is consistent with empirical observations of the outcomes of international CubeSat missions to date.
'Blue Wren' ground station at ANU
The 'Blue Wren' ground station at the Australian National University (see pictures below) has been set up for INSPIRE-2. There are also ground stations at The University of New South Wales and in Strasbourg, France which will communicate with the satellite in orbit.