Abstract:
Since 2019 the number of low-Earth orbit (LEO) satellites has been steadily
increasing due to the deployment of large satellite constellations such as Starlink
and OneWeb. These LEO satellites leave bright trails across telescope detectors,
lowering efficiency and in the worst case introducing systematic errors. There
has been growing concern from the astronomy community on how this will
impact astronomical observations; particularly vulnerable are wide-field surveys
in the optical and near-infrared, such as that carried out by the Microlensing
Observations in Astrophysics (MOA) telescope at the University of Canterbury’s
Mount John Observatory in Takapō. Other observatories around the world have
already reported a marked increase in observations containing satellite streaks,
particularly near the horizon and during twilight. In this research, I aim to
quantify the impact of satellite constellations on the images obtained during
the MOA-II survey. The MOA-II survey observation data present a particular
challenge to analyse due to the very high stellar density of the Galactic fields
it observes. I use the ASTRiDE streak detection algorithm to analyse a subset
of the MOA-II database, ranging from 2018 − 2022. I find no increase in the
number and area of detected streaks over the fives years, though this may be due
to issues with the algorithm that arose in the methodology. I describe the seasonal
variation in streak-affected images, as well as an analysis of the historical cadence
of the MOA-II survey. Suggestions for further work to solve issues in the streak
detection methodology, as well as investigating any additional types of impacts
on the MOA-II survey, are given.
