Seeing is the effect of random fluctuations in the index of refraction throughout the Earth’s atmosphere which result in random fluctuations in the direction of light from a distant source. Scintillation is the random fluctuation of the light intensity received. In 1993, a correlation was found between seeing and scintillation. Using this concept, and by using a non-telescopic method, we can measure seeing during the day, using the sun as the source of light. PoET is the Paranal solar Espresso Telescope that will be connected to the ESPRESSO high resolution spectrograph. Using the Sun as a proxy, PoET will allow us to understand the physical processes responsible for the stellar noise in ultra-high precision spectroscopy studies of exoplanets. PoET will be able to point to any region in the solar disk and obtain a high-resolution spectrum, of spatially resolved region, between 1 and 60 arcsec areas in the solar disk. Therefore, it is crucial to understand the atmospheric conditions during the day to be able to define which aperture PoET will be observing with. In this context, we are implementing a solar seeing measurement instrument that will be used to measure the seeing during the day in Paranal, Chile where PoET will be installed. In this paper, we will discuss the concept behind the instrument, and present its current phase. We will present the optomechanical, electronics, and software-related components; as well as the first on-sky testing measurements.
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