PACKMAN – A portable instrument to investigate space weather
PACKMAN (PArticle Counter k-index Magnetic ANomaly) is an autonomous, light and robust and space weather instrument for operation within the subsurface, surface and atmosphere (as payload in stratospheric balloons) of the Earth. It has been designed using to Commercial Off The Shelf (COTS) components to reduce the cost of each unit and to allow to have multiple units monitoring simultaneously at different sites and also incorporate an open-access approach. The hardware-core of each PACKMAN units, weights around 600 g, including electronics and a plastic designed mechanical support structure. The total weight of the PACKMAN, including a 3D printed enclosure and batteries, is 1kg with a maximum dimension of 30x30x20cm. The enclosure is packed with polystyrene foam to maintain a stable temperature of the electronic components as the temperature plunges to negative 50°C at high altitudes. PACKMAN consumes about 500 mA of current at 12V and can be powered by lithium batteries which are light and have a high-power density. The balloon version of PACKMAN has a camera to record the different phases of the launch and flight. PACKMAN has been deployed at multiple latitudes and altitudes ranging from stratospheric heights (corroborating its TRL8 maturity) to subsurface depths of around 1km. The data from PACKMAN have been compared with the state-of-the-art ground-based observatories, and satellites and scientific observations have been documented. A 3-D network of PACKMAN units operating continuously around the globe, from the subsurface to the stratosphere, would help to improve the understanding of the space weather phenomena, and its implications on the climate and infrastructures. With its straightforward design, PACKMAN is also an excellent tool for education and outreach. This article outlines the building instructions of two types of PACKMAN units: PACKMAN-S for ground-based measurements and PACKMAN-B for stratospheric measurements aboard high-altitude balloons. It also provides guidelines on the data format, to encourage multiple users to build their own PACKMAN instrument and allow sharing a unique formatted data for comparison and thus enable a citizen science approach.