Grand Challenge Initiative – Cusp: rockets to explore solar wind-driven dynamics of the top side polar atmosphere

This is chapter 9 of the State of Environmental Science in Svalbard (SESS) report 2018 (https://sios-svalbard.org/SESS_Issue1).

“The Grand Challenge Initiative – Cusp” (GCI-Cusp), a strategic coordination between the Japanese Aerospace Exploration Agency, NASA, SIOS and UiO, is the largest sounding rocket project ever. Twelve sounding rockets will be launched during the winters of 2018/19 and 2019/20. Each mission has been selected by their respective funding agency as a stand-alone project with the potential to do compelling science. Andøya Space Center can support two simultaneous launches from both Andøya and Ny-Ålesund. Thus, by coordinating missions, we may have up to four rockets in the sky nearly at the same time.

Polar cusps are two funnel-shaped regions in the Earth’s magnetic field, where solar wind particles can enter the polar atmosphere, where their collisions produce the Northern lights. Cusp aurora is the technical term for the Northern lights in daytime. In Svalbard, this phenomenon is visible to the naked eye during December and January. Since Svalbard is the only place in the world where cusp aurora can be studied by rockets, cameras and radars, it is a world class laboratory for studying solar wind interactions with the atmosphere. Major research infrastructure such as the EISCAT Svalbard Radar, the Kjell Henriksen Observatory and SVALRAK has been built to capitalise on Svalbard’s unique location. These ground instruments will be key in defining the launch condition for each rocket.