In the realm of space plasma research, a team of scientists led by Štefan Štverák from the Slovak Academy of Sciences, along with colleagues from the Czech Academy of Sciences, NASA, and the Swedish Institute of Space Physics, has been delving into the challenges of measuring thermal electrons in space plasmas. Their work, published in the journal “Space Science Reviews,” focuses on understanding and mitigating the effects of spacecraft emissions and charging on electron measurements, using data from the Solar Orbiter mission.
The Solar Orbiter, a collaborative mission between ESA and NASA, is designed to perform unprecedented close-up observations of the Sun. One of its instruments, the Electron Analyser System (SWA-EAS), measures electron energy spectra in the solar wind. However, these measurements are often contaminated by electrons emitted from the spacecraft itself, as well as by the spacecraft’s charging in the plasma environment.
To tackle this issue, the researchers employed the Spacecraft Plasma Interaction Software to model the interaction of the Solar Orbiter with the solar wind plasma. They simulated the electron energy spectra as detected by a virtual SWA-EAS experiment, using measured plasma conditions at 0.3 astronomical units (AU) from the Sun. The team found that the simulated data qualitatively agreed with the real data observed by the SWA-EAS detector.
Interestingly, the study revealed that contamination by cold electrons emitted from the spacecraft was observed well above the spacecraft potential energy threshold. This contamination was found to originate from distant spacecraft surfaces. The researchers also noted a slight deviation in the relative position of the break in the simulated spectrum compared to the real observations, suggesting that the actual potential of the SWA-EAS detector with respect to the ambient plasma might differ from the measured spacecraft potential.
The findings of this study have practical implications for the energy sector, particularly in the field of space-based solar power and satellite technology. Understanding and mitigating spacecraft charging and emission effects can improve the accuracy of plasma measurements, leading to better designs for spacecraft and more efficient operation of space-based systems. Moreover, insights gained from studying the solar wind can contribute to advancements in fusion energy research, as the solar wind is a natural laboratory for studying plasma physics.
In conclusion, the research conducted by Štverák and his team sheds light on the complexities of measuring space plasmas and offers valuable insights for the energy industry. Their work, published in the journal “Space Science Reviews,” underscores the importance of accurate plasma measurements for the development of space-based technologies and fusion energy research.
This article is based on research available at arXiv.