Astronomical site selection: On the use of satellite data for aerosol content monitoring

TL;DR

This paper evaluates satellite aerosol data for astronomical site selection, finding that current satellite measurements lack sufficient reliability and emphasizing the need for in situ data for accurate site characterization.

Contribution

It critically assesses satellite aerosol data for astronomical site selection and highlights the necessity of in situ measurements over satellite data alone.

Findings

Satellite aerosol data are not sufficiently reliable for site characterization.

In situ measurements are essential for accurate aerosol assessment.

Satellite data require careful interpretation considering resolution and spectral channels.

Abstract

The main goal of this work is the analysis of new approaches to the study of the properties of astronomical sites. In particular, satellite data measuring aerosols have recently been proposed as a useful technique for site characterization and searching for new sites to host future very large telescopes. Nevertheless, these data need to be critically considered and interpreted in accordance with the spatial resolution and spectroscopic channels used. In this paper we have explored and retrieved measurements from satellites with high spatial and temporal resolutions and concentrated on channels of astronomical interest. The selected datasets are OMI on board the NASA Aura satellite and MODIS on board the NASA Terra and Aqua satellites. A comparison of remote sensing and in situ techniques is discussed. As a result, we find that aerosol data provided by satellites up to now are not reliable enough for aerosol site characterization, and in situ data are required.