SpaceX has been forced to push back the 8th launch of its Starlink low-Earth orbit satellites, due to a tropical storm. Despite this, the company is preparing to tackle the ongoing issue of the visibility of its smallsats in space, with a new ‘sunshading’ technology that could make them invisible to stargazers on Earth.
‘Sunshading’ trial on next Starlink launch
SpaceX has come under fire for the visibility of its Starlink constellation in the skies at night. With millions around the world already spying the lights in the sky, astronomers and stargazers have raised concerns about interference from the eventual mega constellation.
In a bid to appease the angry masses, SpaceX sent up a ‘DarkSat’ in a batch launched in January. This unit was coated in an anti-reflective covering and was noted to be considerably darker than is un-coated cohorts. However, this was not enough to quell the worries of the world’s astronomers.
As such, the next batch to go up with include some units with a new experimental means of ‘sunshading.’ In a tweet, founder Elon Musk confirmed this new method, known as VisorSat, would be deployed, as well as operational methods of reducing visibility, including changes to the solar panel angle.
Thanks! We are taking some key steps to reduce satellite brightness btw. Should be much less noticeable during orbit raise by changing solar panel angle & all sats get sunshades starting with launch 9.
— Elon Musk (@elonmusk) April 22, 2020Advertisement:
Starlink already has permission to become a constellation of 12,000 satellites, although SpaceX has applied for 30,000 more. To put this in perspective, the total number of objects launched into space in human history is just 9,400. As such, the astronomers’ concerns can be understood; hopefully, VisorSat will provide a solution to the concerns.
What is VisorSat?
The issue with Starlink is that the reflectivity of the satellites, along with their proximity to Earth, means the sunlight is bounced off the units and seen on the ground. Other satellites in higher orbits can be seen in this way but tend to be few and far between. With hundreds of Starlink satellites already in orbit and plans for thousands more, the visible trains of light could start to become a real issue.
“Our objectives, generally, are to make the satellites invisible to the naked eye within a week, and to minimize the impact on astronomy, especially so that we do not saturate observatory detectors and inhibit discoveries.”
The concept is set to deploy panels like a sun visor on a car windshield to keep the antennas in shadow. Musk noted that it is made of a special foam that doesn’t interfere with the antennas.
It’s made of a special dark foam that’s extremely radio transparent, so as not to affect the phased array antennas. Looks a lot like a car sun visor.
— Elon Musk (@elonmusk) April 22, 2020
It has not been confirmed at this stage how many of the satellites will feature the VisorSat system.
Next Starlink launch put back by tropical storm
Another 60 Starlink satellites were set to be launched this week, but the mission has been pushed back as a result of inclement weather from Tropical Storm Arthur. The Starlink flight will now take off from Cape Canaveral Air Force Station in Florida on May 27th.
When this launch takes place, it will become the eight deployment for Starlink. To date, 422 of the satellites are already in place in low-Earth orbit, including two prototypes that went up in 2018. SpaceX previously said that a constellation of 400 or more should be capable of ‘minor’ coverage, while 800 would provide ‘moderate’ service.
As such, we could likely see the world’s first true LEO network up and running relatively soon.