SpaceX's Starlink satellites will soon get glare-reducing 'sunshades,' Elon Musk says

A photograph showing SpaceX's first batch of Starlink satellites during launch on May 23, 2019.
A photograph showing SpaceX's first batch of Starlink satellites during launch on May 23, 2019. (Image credit: SpaceX)

SpaceX's Starlink internet satellites will soon sport an accessory to tamp down their surprising brightness.

That brightness worries many astronomers, who say that the huge Starlink constellation could seriously disrupt a variety of scientific observations. And Starlink will indeed be huge, if all goes according to SpaceX's plan: The company has approval to launch 12,000 craft to low Earth orbit (LEO) and has applied for permission to loft 30,000 more. (For perspective, humanity has launched just 9,400 objects to orbit since the dawn of the space age in 1957).

SpaceX founder and CEO Elon Musk has said that the company will find a way to make Starlink craft fade from scientists' sight, predicting that the constellation will end up having no impact whatsoever on astronomical discoveries. SpaceX has been working with the astronomical community to help make this happen, researchers say, and the company has already tried out some mitigation measures.

Related: Starlink: SpaceX's satellite internet project

For example, one of the 60 Starlink satellites that launched atop a Falcon 9 rocket this past January sported an experimental coating to make it less reflective. Observations show that this "DarkSat" is considerably dimmer than its brighter Starlink cohorts, but probably not dim enough to quell most astronomers' concerns about the megaconstellation. 

But SpaceX is taking additional measures as well, which brings us to the new accessory. Musk tweeted the following on Wednesday (April 22), in response to a Twitter follower who wished SpaceX luck on a 60-satellite Starlink launch that day: "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."

He gave some details about the sunshades, which will presumably reduce solar reflection off the satellites' bodies, in a subsequent tweet that day: "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."

The sunshade-equipped satellites will begin flying soon, because Starlink Launch 9 should be just around the corner. Wednesday's liftoff was Launch 7, and Launch 8 is targeted for May.

Each Starlink mission lofts 60 spacecraft. To date, SpaceX has launched 422 of the satellites to LEO, counting two prototypes that went up in February 2018. Musk has said that Starlink can provide "minor" internet coverage with at least 400 satellites and "moderate" service with about 800, so the constellation will likely be operational relatively soon.

The sunshades' effectiveness should also be apparent in short order. Astronomers will doubtless be tracking the modified satellites, hoping they don't stand out too much against the dark sky.

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook

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Mike Wall
Senior Space Writer

Michael Wall is a Senior Space Writer with and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.

  • Lovethrust
    While an impressive technical achievement I can’t imagine what a nightmare 42,000 sats or even a small fraction of that will make for astronomy which typically deals with very light sensitive sensors and hours long exposures. Not to mention the hazards for other sats and spacecraft.
    Just because you can do something doesn’t mean it’s a good idea.
  • AvgJoe
    With the advent of Starship and mass production of satellites (Spacex can build up to 7 per day currently - faster than they can launch them at present), we have an opportunity to put a constellation of cheap, powerful space telescopes into high LEO (1500Km or so - at lower edge of the Van Allen radiiation belt (allowing cheaper electronics) and above the current LEO comms sats. (Which suffer lag if they are placed in higher orbits.)

    This will allow spectacular resolution when used in clusters in a fashion similar to Very Large Array telescopes to drastically boost resolution above and beyond ridding them of atmospheric distortion issues. With a separation on the order of 10,000 km, the effective resolution would be enormous.

    In short, this is both an impediment to existing infrastructure and a doorway to new, cheaper, vastly more powerful telescopes. Using Musk's costs as a guideline for his satellites and multiplying a telescope cost by 10x, you could build and launch hundreds of mass produced telescopes for less than half the price of the James Web telescope. They could be assigned to wokring groups to allow multiple VLA clusters and/or operate individually for earth observations and other less demanding tasks. Spacex indicates they can launch 400 of their satellites at a time in Starship. Imagine launching 40 telescopes at a time for $200 million in sat build costs and $20 million per launch (or a $5mil/satellite + $500k/sat/launch). $2.2billion for 400 satellites vs $10 billion for James Webb. ... just saying.... (not a perfect comparison, but a good indicator that this would be a bargain).

    As they would cover 100% of the sky they could also continuously watch for Near Earth Objects when not otherwise tasked.

    Maintenance costs would also be lower - simply have spares and deorbit sats as needed and the rest pick up the slack by closing gaps with Hall thrusters. Launch a new batch every year as replenishment As for fails that won't de-orbit. It would be relatively easy to build batches of microsats to use Hall thrusters and harpoons to attach to and slowly pull down failed sats as a cleaning service. These would cost even less than Musk's comms satellites and could be launched in a few annual "Clean up" swarms to pull down all the dead objects and keep space "clean".
  • Alexander
    Lovethrust said:
    .... Just because you can do something doesn’t mean it’s a good idea

    Especially if one considers that other players will follow suit, and so will the Chinese, and the Russians if they'll find the cash. The result will be absolute mayhem in LEO that could seriously endanger further missions. I saw the train (Starlink 6, already split in two distinct groups) here in the South of Switzerland and was shocked how bright they were in spite of extremely hazy conditions. I have an inkling that something will stop this madness, bit I'm probably wrong.
  • Truthseeker007
    "The plans to beam highly penetrative 5G milliwave radiation at us from space must surely be one of the greatest follies ever conceived of by mankind. There will be nowhere safe to live."Olga Sheean , Former WHO employee and author of No Safe Place
    The Schumann Resonance is a geomagnetic electric resonance between the surface of the earth and the lower levels of the ionosphere, which has a natural ultra-low frequency and extreme low-frequency signal. They are discovering that the Schumann Resonance signal is correlative with sunspot numbers and has a real physical mechanism located in the D-layer of the ionosphere with an ion and electron density that varies with the S-GMA. The Schumann Resonance would be potentially disrupted by 20,000 5G satellites put into orbit in the D-region of the ionosphere, as this D-region forms the upper boundary of the resonant cavity in which the Schumann Resonance is formed in relation to the earth. Research suggests that the Schumann Resonance signals are the mechanism through which melatonin production is activated. When the Schumann Resonance goes above 7.87 Hz, there is a decrease in melatonin secretion.

    Many feel that the Schumann Resonance is already being altered by all the radiofrequency/microwave (RF/MW) radiation humans are presently creating, and 5G will alter it significantly more. In the process, the 5G may also be creating enough electropollution noise, whether or not it is raising the Schumann Resonance frequency, and therefore disconnecting humanity from accessing the Schumann Resonance itself, and, thus, creating and/or amplifying a variety of acute and chronic disease problems documented in over 10,000 scientific papers that come from these 2G, 3G, and 4G frequencies.