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Modelling solar irradiance from ground-based photometric observations
Chatzistergos, Theodosios; Ermolli, Ilaria; Giorgi, Fabrizio +2 more
Total solar irradiance (TSI) has been monitored from space since 1978, i.e. for about four solar cycles. The measurements show a prominent variability in phase with the solar cycle, as well as fluctuations on timescales shorter than a few days. However, the measurements were done by multiple and usually relatively short-lived missions. The differe…
Synoptic solar observations of the Solar Flare Telescope focusing on space weather
Sakurai, Takashi; Hanaoka, Yoichiro; Morita, Satoshi +2 more
The solar group at the National Astronomical Observatory of Japan is conducting synoptic solar observation with the Solar Flare Telescope. While it is a part of a long-term solar monitoring, contributing to the study of solar dynamo governing solar activity cycles, it is also an attempt at contributing to space weather research. The observations i…
The Electron Proton Helium INstrument as an example for a Space Weather Radiation Instrument
Heber, Bernd; Malandraki, Olga; Posner, Arik +3 more
The near-Earth energetic particle environment has been monitored since the 1970's. With the increasing importance of quantifying the radiation risk for, e.g. for the human exploration of the Moon and Mars, it is essential to continue and further improve these measurements. The Electron Proton Helium INstrument (EPHIN) on-board SOHO continually pro…
Assessment of CESE-HLLD ambient solar wind model results using multipoint observation
Feng, Xueshang; Wei, Fengsi; Li, Huichao
For a three-dimensional magnetohydrodynamics solar wind model, it is necessary to carry out assessment studies to reveal its ability and limitation. In this paper, the ambient solar wind results of year 2008 generated by the CESE-HLLD 3D MHD model are compared with multipoint in-situ measurements during the late declining phase of solar cycle 23. …
MoMo: a new empirical model of the Mars ionospheric total electron content based on Mars Express MARSIS data
Peter, Kerstin; Witasse, Olivier; Kofman, Wlodek +5 more
Aims: Several scientific landers and rovers have reached the Martian surface since the 1970s. Communication between the asset (i.e., lander or rover) and Mars orbiters or Earth antennas uses radio signals in UHF to X-band frequencies passing through the Mars' ionosphere. It is consequently necessary to take into account electron density variation …
Estimating the solar wind pressure at comet 67P from Rosetta magnetic field measurements
Madanian, Hadi; Timar, Aniko; Nemeth, Zoltan +3 more
Aims: The solar wind pressure is an important parameter of space weather, which plays a crucial role in the interaction of the solar wind with the planetary plasma environment. Here we investigate the possibility of determining a solar wind pressure proxy from Rosetta magnetic field data, measured deep inside the induced magnetosphere of comet 67P…
Artificial intelligence unfolding for space radiation monitor data
Daglis, I. A.; Sandberg, I.; Evans, H. +5 more
The reliable and accurate calculation of incident particle radiation fluxes from space radiation monitor measurements, i.e. count-rates, is of great interest and importance. Radiation monitors are relatively simple and easy to implement instruments found on board multiple spacecrafts and can thus provide information about the radiation environment…
Analysis and interpretation of inner-heliospheric SEP events with the ESA Standard Radiation Environment Monitor (SREM) onboard the INTEGRAL and Rosetta Missions
Sanahuja, Blai; Papaioannou, Athanasios; Anastasiadis, Anastasios +6 more
Using two heliospheric vantage points, we study 22 solar energetic particle (SEP) events, 14 of which were detected at both locations. SEP proton events were detected during the declining phase of solar cycle 23 (November 2003-December 2006) by means of two nearly identical Standard Radiation Environment Monitor (SREM) units in energies ranging be…
Shock deceleration in interplanetary coronal mass ejections (ICMEs) beyond Mercury's orbit until one AU
Krupar, Vratislav; Grison, Benjamin; Souček, Jan +4 more
The CDPP propagation tool is used to propagate interplanetary coronal mass ejections (ICMEs) observed at Mercury by MESSENGER to various targets in the inner solar system (VEX, ACE, STEREO-A and B). The deceleration of ICME shock fronts between the orbit of Mercury and 1 AU is studied on the basis of a large dataset. We focus on the interplanetary…
The detection of ultra-relativistic electrons in low Earth orbit
Dammasch, Ingolf E.; Berghmans, David; Dominique, Marie +6 more
Aims: To better understand the radiation environment in low Earth orbit (LEO), the analysis of in-situ observations of a variety of particles, at different atmospheric heights, and in a wide range of energies, is needed.
Methods: We present an analysis of energetic particles, indirectly detected by the large yield radiometer (LYRA) instr…