• The altitude of green OI 557.7 nm and blue N2+ 427.8 nm aurora 

      Whiter, Daniel K.; Partamies, Noora; Gustavsson, Bjorn Johan; Kauristie, Kirsti (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-06)
      We have performed a large statistical study of the peak emission altitude of green O(1D2–1S0) (557.7 nm) and blue 1 N (427.8 nm) aurora using observations from a network of all-sky cameras stationed across northern Finland and Sweden recorded during seven winter seasons from 2000 to 2007. Both emissions were found to typically peak at about 114 km. The distribution of blue peak altitudes is more ...
    • Challenges and Strategic Research Plans for Earth and Heliosphere: Research Infrastructures, Projects and Initiatives 

      Mann, Ingrid; Kauristie, Kirsti; Bamford, Ruth; McCrea, Ian; Moen, Jøran Idar; Oksavik, Kjellmar; Yamauchi, Masanori; Johnsen, Magnar Gullikstad; Turunen, Esa (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-24)
      We describe existing research infrastructures relevant for space weather and open issues of space weather research including the need for sustainable observation networks and for high-quality data products as basis for model development. The local relevance in Europe for studies of the ionosphere at high latitude is described. We propose as possible a way forward to sustain space weather research ...
    • Radar—CubeSat Transionospheric HF Propagation Observations: Suomi 100 Satellite and EISCAT HF Facility 

      Kallio, Esa; Kero, Antti; Harri, Ari-Matti; Kestilä, Antti; Aikio, Anita; Fontell, Mathias; Jarvinen, Riku; Kauristie, Kirsti; Knuuttila, Olli; Koskimaa, Petri; Loyala, Jauaries; Lukkari, Juha-Matti; Modabberian, Amin; Niittyniemi, Joonas; Rynö, Jouni; Vanhamäki, Heikki; Varberg, Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-20)
      Radio waves provide a useful diagnostic tool to investigate the properties of the ionosphere because the ionosphere affects the transmission and properties of high frequency (HF) electromagnetic waves. We have conducted a transionospheric HF-propagation research campaign with a nanosatellite on a low-Earth polar orbit and the EISCAT HF transmitter facility in Tromsø, Norway, in December 2020. In ...
    • Reconstruction of precipitating electrons and three-dimensional structure of a pulsating auroral patch from monochromatic auroral images obtained from multiple observation points 

      Fukizawa, Mizuki; Sakanoi, Takeshi; Tanaka, Yoshimasa; Ogawa, Yasunobu; Hosokawa, Keisuke; Gustavsson, Björn Johan; Kauristie, Kirsti; Kozlovsky, Alexander; Raita, Tero; Brändström, Urban; Sergienko, Tima (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-12)
      In recent years, aurora observation networks using high-sensitivity cameras have been developed in the polar regions. These networks allow dimmer auroras, such as pulsating auroras (PsAs), to be observed with a high signal-to-noise ratio. We reconstructed the horizontal distribution of precipitating electrons using computed tomography with monochromatic PsA images obtained from three observation ...