December 17, 2019 • Evelyn J. Arevalo
SpaceX plans to fund their vision of colonizing Mars by offering internet services. They will deploy a mega-constellation of satellites named Starlink. These satellites will beam low-latency, high-speed internet across Earth. They are scheduled to launch the third batch of 60 Starlink internet satellites before the end of December. The first batch of 60 satellites was launched in May, following the second batch of 60 launched in November. These were more reflective in the darkness than expected. Visible in train-like formations before spreading out weeks later after each deployment. SpaceX faced complaints from astronomers about Starlink satellites being too bright in the night sky. In response SpaceX will now experiment with a new coating to make them less bright.
STARLINK衛星のトレイン。もうちょっと高感度のカメラで望遠でとらえたものです。銀河鉄道のイメージから遠ざかってしまいますが、衛星の数が数えられそうですね。60機のうち何機映っているでしょうか？ pic.twitter.com/kjbnDtMrJJ— 三島和久・ｱﾆﾘﾝ・レモンパスタ部 (@C6H5NH2) November 12, 2019
SpaceX President and Chief Operating Officer, Gwynne Shotwell, said the satellites' reflectivity was a surprise, “There are lots of people that have looked at Starlink and looked at the satellites, lots of people knew what we were doing, and no one thought of this. We didn’t think of it. The astronomy community didn’t think of it. It happened … Let’s go figure that out.” And added that the company wants to do the “the right thing” to ensure the night sky remains clear for astronomers and inspiration.
“Astronomy is one of a few things that gets little kids excited about space. There are a lot of adults that get excited, too, who either depend on it for their living or for entertainment. But we want to make sure we do the right thing, to make sure little kids can look through their telescopes. It’d be cool for them to see a Starlink. I think that’s cool. But they should be looking at Saturn and the moon.”
SpaceX will test an experimental coating that is meant to make Starlink satellites less reflective. According to Shotwell, the coating will go on the bottom of one of the 60 new satellites that will be deployed into orbit this month. They would like to test out the coating first, before applying it to more satellites next year. They want to see if the satellite coating's anti-reflective properties could affect the satellite's performance due to thermal changes. Shotwell believes the solution will be found over trial and error. She told reporters at SpaceX headquarters:
“This next batch has one satellite that we’ve put a coating on the bottom. This is going to be an experiment … We’re going to do trial and error to figure out what’s the best way to get this done. But we are going to get it done.”
The Starlink satellites for next launch have arrived to Cape Canaveral from the Starlink factory in Redmond, Washington, for final launch preparations.
Each Starlink satellite is relatively small compared to other satellites in orbit, they're flat about the size of an office desk with a single solar array, weighing 500.5 pounds.
To operate, each satellite will link to 4 neighboring satellites by using lasers, no other internet-providing satellites do this. The satellites transmit their signal via 4 phased array radio antennas. This flat type of antenna can transmit in multiple directions and frequencies without ever moving. Starlink will bypass the limitations of of our current internet infrastructure by beaming data over Earth's surface at nearly the speed of light. Every deployment of 60 satellites could deliver 1 terabit of bandwith, that could potentially support 40,000 users streaming ultra-high-definition content at the same time. The satellites are equipped to allocate broadband resources in real time, placing capacity where its most on demand. Also have the capability to direct signal away from areas where it might cause interference to other systems in space or on the ground. Starlink will require associated ground transceivers. Customers would need a box terminal to receive internet connection from space.
SpaceX has approval from the Federal Communications Commission (FCC) to launch and operate up to 12,000 Starlink satellites in the coming years. After 24 rocket launches of 60 satellites each, they expect to achieve global internet coverage.