The precise measurement of the solar spectrum outside the atmosphere and its variability are fundamental inputs for:
- solar physics (Sun modeling)
- terrestrial atmospheric photochemistry
- the Earth's climate (climate 's modeling)
The role of solar variability on climate change remains a topic of strong scientific and societal interest. An international scientific team, with an important role for the Royal Belgian Institute for Space Aeronomy (BIRA-IASB), has accurately determined a new solar reference spectrum from measurements made by the SOLAR/SOLSPEC instrument on board the International Space Station.
The study behind this story was published in the journal Astronomy and Astrophysics in November 2017.
The new Solar Reference Spectrum (SOLAR - ISS) was obtained from the measurements made by the SOLAR SPECtrometer (SOLSPEC) instrument of the SOLAR payload onboard the International Space Station.
SOLAR/SOLSPEC is the result of a long collaboration between the Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS) and the Royal Belgian Institute for Space Aeronomy (BIRA-IASB) that already made possible to measure the solar spectrum from several space missions (ESA and NASA).
The SOLAR/SOLSPEC instrument data will also be used to track the spectral variability of solar irradiance over nearly a solar cycle (from 2008 to 2017). These are essential and valuable data for modeling the Earth's climate with climate chemistry models of the atmosphere.
Indeed, it is now known that the influence of solar variability on the Earth's atmosphere and climate is associated with extremely complex mechanisms and that their understanding can not be reduced to mere considerations with regard to the radiation balance of the Earth. The spectral variations of solar irradiance (influence of wavelength) play a significant role in the chemistry of the Earth's atmosphere and climate.
SOLAR-ISS: A new reference spectrum based on SOLAR/SOLSPEC observations, M. Meftah, L. Damé, D. Bolsée, A. Hauchecorne, N. Pereira, D. Sluse, G. Cessateur, A. Irbah, J. Bureau, M. Weber, K. Bramstedt, T. Hilbig, A. Sarkissian, R. Thiéblemont, M. Marchand, F. Lefèvre, S. Bekki, Astronomy and Astrophysics, November 2017.