OBSERVATIONS OF THE EVOLUTION OF THE SOLAR DIAMETER AND SOLAR CONSTANT WITH CUBSAT 3U SATELLITES
DOI:
https://doi.org/10.68302/std2026.vol2.185Keywords:
diameter of the Sun, differential rotation, shape of the solar disk, solar astrometryAbstract
The article presents a CubeSat project with a 3U form factor designed for simultaneous measurements of the solar diameter, its differential rotation, and the solar constant. The optimal mission duration is discussed – up to a maximum of 2 years – in order to investigate the nature of variability of these parameters and their interrelationships. The satellite will have a mass of up to 3 kg and a payload of 2 kg, consisting of three optical instruments that will enable measurements of the solar diameter and shape, as well as the total solar irradiance and ultraviolet (UV) radiation. It is planned that the satellite will be placed in low Earth orbit and will have an operational lifetime of approximately one and a half years, after which it will be replaced by an identical satellite in the same low Earth orbit. This approach allows for long-term mission continuity due to the low cost of the satellite and launch expenses. The mission will provide valuable data on the Sun’s diameter, rotation, and radiation, and will include ground-based observations for validation of measurements from space. The main scientific objectives to be achieved by the satellite mission include:
- Confirmation of variations in the solar diameter (and validation of ground-based measurements and their accuracy);
- Establishment of the relationship between solar diameter, total irradiance, and differential rotation;
- Measurement of the Sun’s oblateness and shape to a high order of precision.
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Copyright (c) 2026 Desislava Teneva, Penka Stoeva, Ognyan Ognyanov, Alexey Stoev, Mina Spasova
This work is licensed under a Creative Commons Attribution 4.0 International License.
