Blar i forfatter "Havnes, O."

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    • The effect of electron bite-outs on artificial electron heating and the PMSE overshoot. 

      Belova, E.; Kassa, M.; Havnes, O. (Journal article; Peer reviewed; Tidsskriftartikkel, 2005-12-23)
      We have considered the effect that a local reduction in the electron density (an electron bite-out), caused by electron absorption on to dust particles, can have on the artificial electron heating in the height region between 80 to 90 km, where noctilucent clouds (NLC) and the radar phenomenon PMSE (Polar Mesospheric Summer Echoes) are observed. With an electron density profile without ...

    • First Simultaneous Rocket and Radar Detections of Rare Low Summer Mesospheric Clouds 

      Havnes, O.; Latteck, R.; Hartquist, T.W.; Antonsen, T. (Journal article; Peer reviewed, 2018-06-10)
      On 30 June 2016 a layer of dust, possibly meteoric smoke particles (MSPs), was observed with a rocket borne probe at 69.29°N, 16.02°E and altitudes of ~74 km where patchy thin cloud layers, detected with the Middle Atmosphere Alomar Radar System, were present. The rocket traversed a layer with a net positive dust charge density of ~107 unit charges per cubic meters and a number density of neutral ...

    • The red-sky enigma over Svalbard in December 2002 

      Sigernes, F.; Lloyd, N.; Hoppe, U.-P.; Degenstein, D.; Shumilov, N.; Moen, J.; Gjessing, Y.; Havnes, O.; Skartveit, A.; Raustein, E.; Ørbæk, J.B.; Deehr, CS (Journal article; Tidsskriftartikkel; Peer reviewed, 2005-07-27)
      On 6 December 2002, during winter darkness, an extraordinary event occurred in the sky, as viewed from Longyearbyen (78° N, 15° E), Svalbard, Norway. At 07:30 UT the southeast sky was surprisingly lit up in a deep red colour. The light increased in intensity and spread out across the sky, and at 10:00 UT the illumination was observed to reach the zenith. The event died out at about 12:30 UT. Spectral ...

    • The red-sky enigma over Svalbard in December 2002 

      Sigernes, F.; Shumilov, N.; Lloyd, N.; Havnes, O.; Lorentzen, D.A.; Neuber, R.; Hoppe, Ulf-Peter; Degenstein, D.; Moen, J.; Gjessing, Y.; Skartveit, A.; Raustein, E.; Ørbæk, J.B.; Deehr, C.S. (Journal article; Peer reviewed; Tidsskriftartikkel, 2005-07-27)
      On 6 December 2002, during winter darkness, an extraordinary event occurred in the sky, as viewed from Longyearbyen (78° N, 15° E), Svalbard, Norway. At 07:30 UT the southeast sky was surprisingly lit up in a deep red colour. The light increased in intensity and spread out across the sky, and at 10:00 UT the illumination was observed to reach the zenith. The event died out at about 12:30 UT. Spectral ...