More than three years after the first launch, the satellite constellation Starlink brings Internet to various regions of the world. At the same time, its presence in the sky caused controversy among the astronomical community, since hinders scientific work in ground-based observatories. While SpaceX has already made adjustments to minimize glare from the sun, the company it was proposed to solve the problem in the next generation of satellites.
SpaceX has shared a paper detailing the steps it will take to reduce the brightness of its constellation due to reflections from the sun. Although the company suggested using sun visors To block reflections from the bottom of the chassis, this solution affects the performance of the satellite. Material blocks laser channels needed to expand coverage. Similarly, visors create significant drag, resulting in higher fuel consumption.
Since sun umbrellas are not a viable alternative, SpaceX decided to use RF reflective films to scatter most of the sunlight. While this solution is not perfect, the company is already working on a new version that will apply to the next generation of Starlink.
The second generation of Starlink will be “invisible” to the human eye
According to the document provided by SpaceX, the second generation of Starlink will be larger. The satellites will have a higher surface area to mass ratio and will use three techniques for softening shine.
The first is to use a new version of a mirror film capable of reducing gloss by more than 10 times, compared to the current one. According to SpaceX, the core of this film is a Bragg mirror made up of several thin layers of plastic with different refractive indices. The layers create interference patterns inside to reflect light and are coated with titanium dioxide and silicon dioxide to prevent degradation.
Another solution would be point solar panels away from the sun when satellites cross the line dividing day and night. Although this maneuver will reduce energy by 25%SpaceX says the second generation of Starlink is ready to go with no issues.
Satellites will use darker materials
Finally, Starlink satellites will use darker materials on some surfaces. SpaceX developed low reflective black which you will use to paint the various components of the satellite that cannot be filmed. According to the company, this paint has a specular peak five times lower than the darkest one that can be used in space.
Although the second generation Starlink promises to be invisible to the human eye, there will be times when this is not possible. SpaceX said that when the satellites disperse after launch and enter orbit to begin their work, they will be fully visible. This is because they cannot regulate solar panels as they require most of the energy to be captured. They will also be visible during collision avoidance maneuvers or at the end of their service life.
SpaceX said it will continue to implement methods to reduce the brightness of its second-generation Starlink satellites.
Source: Hiper Textual
