Over the next few weeks, the company will observe how well the layer works and study the effects of the coating on the satellite itself. Based on this study, the company will decide whether to proceed further with the coating or not
FREMONT, CA: SpaceX is looking into reducing the brightness of its Starlink satellites as astronomers continue to remain worried about the harmful effect that system and other mega-constellations will have on their field. Amongst the 60 Starlink satellites launched on January 6, SpaceX featured a satellite with an experimental coating intended to reduce its brightness. Over the next few weeks, the company will observe how well the layer works and study the effects of the coating on the satellite itself. Based on this study, the company will decide whether to proceed further with the coating or not.
The level of brightness of the satellites was a surprise to the company itself, according to SpaceX President Gwynne Shotwell. "Our level of brightness and visibility was a surprise to us," said Patricia Cooper, vice president of satellite government affairs for SpaceX. "The brightness is affected by several issues. The Starlink satellites initially appear bright when released in a lower parking orbit, and the configuration of each satellite’s single large solar array when raising its orbit can also influence its brightness. Once in a final operating orbit of 550 kilometers, the spacecraft brightness decreases to a visual magnitude of about five, making them visible to the naked eye only in darker night skies."
The unique design of the satellites made it difficult for scientists to determine the cause of the brightness. "It turns out, we think, that surfaces that scatter light, or reflect light diffusely, are also significant contributors," Cooper said. This led to the testing of the surfaces on the experimental satellites, nicknamed DarkSat, to reduce the reflectivity of the satellites. Although DarkSat is now in orbit, it will take some time to see how effective it is. Also, the satellite is not expected to reach its final operational orbit before the end of February, after which actual measurements can be taken.
SpaceX will be looking to resolve this issue immediately but will continue to launch the satellites with the original design in the meanwhile. This decision has been frowned upon by many astronomers. The Starlink satellites are programmed to be operational for five years.