Starlink satellites are giant flat, square metal pancakes with tall, flat-segmented solar panels, and they now have one preferred attitude during their rise from deployment altitude (low, so easy to quickly deorbit the duds) to operational altitude and phasing within a given inclination ring, and a second preferred attitude once operational.
Question: Are Starlink satellites flaring? In the same way that the occasional geometry occurred when a near specular reflection of the Sun on to Earth's surface occurs for other satellites, does this happen for Starlinks? Or do the now fairly well established preferred attitudes discussed above pretty much preclude any flaring?
[Answer]
SpaceX's Starlink update blog post ASTRONOMY DISCUSSION WITH NATIONAL ACADEMY OF SCIENCES (posted over a year ago) has a very nice write-up on Starlink brightness:
When sunlight hits a specular surface of the spacecraft and reflects, the vast majority of light reflects in the specular (mirror reflection) direction, which is generally out toward space (not toward Earth). Occasionally when it does, the glint only lasts for a second or less. In fact, specular surfaces tend to be the dimmest part of the satellite unless you are at just the right geometry.
The blog makes no mention of this phenomenon being exclusive to the post-launch/phasing time periods. I could not find any pictures/video of a Starlink flare occurring while in the operational orbit.
