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arXiv · 2301.01601

The BlueWalker 3 Satellite Has Faded

Anthony Mallama·Richard E. Cole·Scott Tilley
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Abstract

Observations of BlueWalker 3 (BW3) beginning on December 8 of this year indicate that its apparent brightness had decreased. We postulate that the orbital beta angle and resultant solar power considerations required an adjustment to the satellite attitude around that time. So, the nominally zenith facing side of the flat-panel shaped spacecraft, which supports the solar array, was tilted toward the Sun. Consequently, the nadir side, which is seen by observers on the ground, was mostly dark. Thus, BW3 has generally appeared faint and on some occasions was not seen at all. The amount of fading was up to 4 magnitudes. Numerical modeling indicates that the amount of tilt was in the range 13{\deg} to 16{\deg}. This situation indicates the improvement in the appearance of BW3 from the ground that can be achieved with small tilts of the spacecraft. Satellite operators and astronomers can jointly address the adverse impact of bright satellites on celestial observations based on this finding.

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Anthony Mallama, Richard E. Cole, Scott Tilley. 2022-12-26. The BlueWalker 3 Satellite Has Faded. https://arxiv.org/abs/2301.01601

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