Starlink dark coating reduces reflectivity by half
Astronomers in Japan have now confirmed that the dark coating SpaceX has been putting on its more recent Starlink satellites has successfully reduced their reflectivity by half.
They looked at the satellites across a range of wavelengths.
Observations conducted from April to June 2020 revealed for the first time in the world that artificial satellites, whether coated or not, are more visible at longer wavelengths, and that the black coating can halve the level of surface reflectivity of satellites. Such surface treatment is expected to reduce the negative impacts on astronomical observations.
Knowing this detail will allow commercial satellite companies such as SpaceX to further refine their coatings to better hide their satellites from ground-based telescopes.
While good news, it doesn’t change the fundamental lesson that astronomers need to learn. They must move their telescopes off the Earth and into space. In the long run ground-based astronomy is a dead-end.
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Astronomers in Japan have now confirmed that the dark coating SpaceX has been putting on its more recent Starlink satellites has successfully reduced their reflectivity by half.
They looked at the satellites across a range of wavelengths.
Observations conducted from April to June 2020 revealed for the first time in the world that artificial satellites, whether coated or not, are more visible at longer wavelengths, and that the black coating can halve the level of surface reflectivity of satellites. Such surface treatment is expected to reduce the negative impacts on astronomical observations.
Knowing this detail will allow commercial satellite companies such as SpaceX to further refine their coatings to better hide their satellites from ground-based telescopes.
While good news, it doesn’t change the fundamental lesson that astronomers need to learn. They must move their telescopes off the Earth and into space. In the long run ground-based astronomy is a dead-end.
The support of my readers through the years has given me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Four years ago, just before the 2020 election I wrote that Joe Biden's mental health was suspect. Only in this year has the propaganda mainstream media decided to recognize that basic fact.
Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Even today NASA and Congress refuse to recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
Please consider supporting my work here at Behind the Black.
You can support me either by giving a one-time contribution or a regular subscription. There are five ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation:
5. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above. And if you buy the books through the ebookit links, I get a larger cut and I get it sooner.
We were able to see the very first Starlink “train” of satellites within 24 hrs of launch.
Probably, the most astounding, artificial sight in the heavens I’ve ever witnessed.
Since then, on multiple attempts, even under optimum viewing conditions, we’ve never seen another Starlink.
Random satellites everywhere, but zero Starlinks.
Bummer.
Just because they are painted black doesn’t mean they won’t still be in the way of telescopes.
There is also a typo – most should be must.
Bob L. Thank you. Typo fixed.
Captain, I saw a Starlink train (the second time I’ve seen it) bigger than life just a few nights ago. The first time I saw a Starlink train, probably about a year ago, it scared the willies out of me because I had no idea what it was. I can only wonder what the earth’s current stone-age folks think when they see it.
Mr. Z, fascinating that ground-bound astronomy is destined to be obsolete. I wonder if the possibility might exist that it will still have some unforeseen valuable application that can only be achieved earth-bound?
Also Mr. Z or anyone knowledgeable, why do some satellites apparently blink off like someone flicked a switch, or blink on, at random sometimes? Or both within a 20 minute period from what looks earthbound like a fixed position? What is a satellite doing when it blinks on again and a short (relatively!) beam of light emits from it, and within a half second blinks off again? What’s the satellite doing, I wonder? Amazing tech.
Janyuary: The blinking on and off by satellites could be caused by two things. First, the angle of their solar panels might be catching sunlight and sending down to the observer, but only for a short time.
Second, they simply could be moving in and out of sunlight, based on their orbit.
Thank you, Mr. Z. I’ll remember those dynamics may be at play next time I see it happen.
As an observer of satellites, another reason for it “blinking” is it is tumbling or spinning. Sometimes they are not satellites, but spent upper stages.
Jay, thank you, reflecting from angles of tumbling craft makes good sense. From my perspective on the ground, then, does that blinking satellite appear to remain in the same place? Even if it is tumbling? It must …
Thanks again!
Hi Janyuary,
OK, if it is in the same place and blinking it is probably a plane’s lights or it is a star. Some stars like Arcturus and Capella looks like they are blinking. Are you sure it is not a plane or helicopter going towards or away from you? I know some student pilots from the nearby airport who fly at night look like they are hanging in one spot. If it is slow, it is an airplane.
If a satellite is not moving in relation to you, it would be in geostationary orbit, but that orbit is about 23k miles away circling the equator south of you (I assume you are in the U.S.). Plus, you could not see it at that distance with your eyes. You can see those satellites with a telescope though.
Thank you, Jay!
Maybe I’ll ask Santa for a telescope, though sky visibility on the California coast a few dozen miles north of Vandenberg AFB ain’t that great.
The satellites (I assume that’s what they are) don’t really blink. They simply are shining there in the same spot like a bright star … and then are gone, they go out. For minutes at a time or more .. then as I’m standing around wasting time looking at the sky and thinking about nuttin’ in pertikewlar, (I’m a night owl by nature) the star suddenly reappears and stays that way. Then after a minute or two, goes off again. I’ve seen this phenomenon at least a half dozen times over the years. Time is usually between 3:30 and 4:30 am, in the eastern sky.
I am absolutely certain that is is not a helicopter or an airplane. Positive. Not at that altitude, and not over this terrain.
Thank you, Jay!