SpaceX says 60 Starlink satellites will grow harder to see

In this screengrab taken from a video shot by Marco Langbroek, a group of SpaceX Starlink satellites passes over the Netherlands
In this screengrab taken from a video shot by Marco Langbroek, a group of SpaceX Starlink satellites passes over the Netherlands—quite a sight for skygazers

SpaceX said Friday that the first 60 satellites in its "Starlink" constellation, which is intended to provide internet from space, will be less and less visible from Earth as they reach their final orbit.

Elon Musk's company created a must-see event for space enthusiasts when it launched all 60 satellites simultaneously on May 23—a series of bright lights ascending through the .

Over the past week, several observers have photographed and filmed the line of satellites, which pass over in just a few minutes.

But astronomers fear the constellation of broadband-beaming satellites, which could one day grow to as many as 12,000, could ruin scientific observation of the skies from telescopes.

Until now, Musk had downplayed the concerns—earning criticism along the way.

But on Friday, the company seemed to address the issue.

SpaceX announced that "all 60 satellites have deployed their solar arrays successfully, generated positive power and communicated with our ."

But the statement then said that "the observability of the Starlink satellites is dramatically reduced as they raise orbit to greater distance and orient themselves."

The satellites were released all at once by a Falcon 9 rocket at an altitude of 280 miles (450 kilometers). They progressively separated from one another and deployed the .

In the coming three to four weeks, each will take position in a relatively low orbit of 340 miles (550 kilometers).

Scientists had already noted that they were less visible in recent days.

Starlink will become operational once 800 satellites have been activated, which will require a dozen more launches.


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SpaceX launches first 60 satellites of its internet network

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May 31, 2019
Quite a spectacle, though. I may go looking for the SpaceX "sky train" right after one of the future launches.

May 31, 2019
Photon Absorbing Paint

If only these satellites had been stealthy
been camouflaged
been sneaky
if only
in this inky orbital
this inky blackness
had a little photon absorbing paint
then
no one needed to have ever known
This advance party was in orbit!

Jun 01, 2019
Musk is a menace. As long as satellites use solar panels for power, they will be highly reflective. Right now, 1/3 of ALL astronomy images are compromised by satellite tracks. If this jack--- has his way, ALL of them will. Way to ruin a scientific discipline.

Jun 01, 2019
As is being constantly pointed out
Thorium Boy> Musk is a menace. As long as satellites use solar panels for power, they will be highly reflective. Right now, 1/3 of ALL astronomy images are compromised by satellite tracks. If this jack--- has his way, ALL of them will. Way to ruin a scientific discipline.

With these ever increasing number of satellites
What with these ever increasing shards of metal
Colliding at 36,000mph
Into nano shards
The day will come
Musk's dream will imprison us to planet earth
Unless
Space ferries are thick skinned

Jun 01, 2019
Musk is a menace. As long as satellites use solar panels for power, they will be highly reflective. Right now, 1/3 of ALL astronomy images are compromised by satellite tracks
-which isnt true.
If this jack--- has his way, ALL of them will. Way to ruin a scientific discipline.
-So you're saying that even though scientists can mask and filter existing sats and debris, they wont be able to handle these additional sats because it's just too hard or something?

I guess then, according to you, we shouldn't be orbiting any more sats at all? Because you know, most sats are far larger and nastier than these.

Jun 01, 2019
So what is the estimated magnitude of these objects when they reach their planned altitude. At higher latitudes, satellites are visible all night long. If you do astro-photography, there are few satellites that do not show up in an image. So while you may not see them with your eyes, your instrumentation will.

Jun 01, 2019
"But astronomers fear the constellation of broadband-beaming satellites, which could one day grow to as many as 12,000, could ruin scientific observation of the skies from telescopes."

How many more stars do they need to look at? What's the point? Get a real job.

Jun 02, 2019
Facebook, paypal, bitcoin, Palantir, and Gmail were bad enough.

Why should our night sky be ruined just so the NSA can play more spy-games by monopolizing and bankrupting worldwide local internet providers with this money-losing, satellite-crashing dog of a program?

Jun 02, 2019
Musk is a menace. As long as satellites use solar panels for power, they will be highly reflective.


Not if they rotate the panel so that Sun reflections into night parts of the Earth are minimized.

Jun 02, 2019
Look, Musk's Mars "prototype" made of aluminum foil, and blown over by a windstorm, was pure propaganda to develop his "street credibility" as a "privatized" "entrepreneur" in space development so the US government could fuel him with unlimited billions to make this prison planet surveillance system a reality. Same story as Google, facebook, etc.

This system has more capability than merely bankrupting international sat-com and local government ISPs, however. Because it orbits so ridiculously and dangerously crashy low, it can scoop up other electronic surveillance, like ground based cell-phone and broadband, and it creates a protective shell in wartime to jam all other satellites out of relevance. In, short, this is a WWIII device, if not a WWIII generator.


Jun 02, 2019
and it creates a protective shell in wartime


You know, that's actually within the realm of possibility. There's going to be a grid of satellites flying every 500-600 km on a very low orbit, and if you place a small explosive in each and detonate them at once, it creates a dense shell of debris that effectively prevents any rocket launch for the next 12-15 months until the pieces fall down by air drag.

So, if you try to launch an ICBM, it's almost guaranteed to get pelleted by hypersonic pieces of the satellites and break down as it has to pass twice through the shell of debris, on the way up and on the way down. Or, the new Russian missile that skims the top of the atmosphere - it's going to fly head-on into the field of debris.

That means you can throw a blanket over the earth to prevent enemies from launching nuclear weapons while you launch a conventional invasion on them.


Jun 02, 2019
That said, Musk's satellites are going to pose a problem for the space launch industry anyhow because you now have to avoid the constellation.

7,500 satellites spread evenly across the globe would mean approximately 86 orbits with 86 satellites in each, resulting in a grid of satellites with a separation of 460 km, give or take a few. They're traveling at around 7.7 km/s so it takes the satellites 1 minute to travel 460 km along their orbits which are oriented north-south, and about 17 minutes for the earth to turn around the distance east-west.

That's 86 bands of satellites that sweep around the earth. Why this is a huge problem is because once you're up there at 340 km, your rocket or satellite is already going sideways in the east-west direction as it climbs to higher orbits, so you're aiming at a very narrow gap to pass between the bands. If you cross the bands and your timing is 30 seconds off, you risk a collision.

Musk is basically building space Frogger.

Jun 02, 2019
Even getting to the ISS will be tricky, since the space station orbits above the proposed Starlink main constellation.

When you send a re-supply mission to the ISS, you first climb up to a low orbit and then start chasing the space station around the earth. The lower orbit goes around faster, so you close up the distance and gradually raise your orbit towards the ISS orbit to slow down your approach speed.

But this means you have to slowly climb up through the Starlink constellation that orbits between the earth and the ISS at right angles to the orbit of the ISS. If you don't do it exactly right, one of the Starlink satellites can side-swipe you at 7.7 km/s with so much energy that your orbiter will simply explode.


Jun 02, 2019
Another way to do it would be to shoot past the ISS orbit and quickly climb up through the Starlink constellation, then start lowering your orbit while the ISS catches up with you - but this requires a bigger rocket and more fuel, or less payload per launch.


Jun 02, 2019

Here's an example of the proposed constellation:

http://www.scatma...rbit.jpg

In order to get to the ISS, you have to pass through the gaps in that grid. Trouble is, the grid keeps spinning around the earth, so you can't just slowly rise through one of the holes - if you stick around too long at the altitude of the Starlink orbital shell, you're at a very high risk of getting sideswiped.

unless of course you pick your orbit along with the grid so you can synchronize with it, but this is not optimal for most launches because you use less fuel by launching in the direction of the earth's rotation, which puts you into an orbit that goes against the grain.

This also raises the question of what happens with space junk that is in decaying orbits, because they will pass through the Starlink shell and their orbital decay is slow enough that they will spend significant time at that altitude. One of them will eventually hit a Starlink satellite, and spread debris

Jun 02, 2019
It will be interesting to see whether Musk will add any sort of active collision avoidance in the grid, because it would be perfectly possible for the Starlink satellites to dodge incoming space junk or ascending rockets if only you know where and when they will intersect with the shell.

Trouble is, if you get it wrong just once and there is a collision, all goes hang because the debris from the explosion will produce millions of particles which are impossible to track, which causes the Kessler syndrome as they hit other Starlink satellites, disable them, and cause them to crash with more stuff.


Jun 04, 2019
It will be interesting to see whether Musk will add any sort of active collision avoidance in the grid
-But not interesting enough to actually look??

"SpaceX's new satellites will dodge collisions autonomously... Musk said the satellites his company launches will avoid potential collisions on their own. And Mark Juncosa, the SpaceX executive in charge of developing the Starlink satellites, downplayed concerns when answering press inquiries on the matter last week. "It might be worth mentioning for people that are not in the space industry … space is really big," he said."

"When notified of a potential conjunction with another object in space, their software will decide whether and how to maneuver, and communicate that information back to CSpOC. It's not clear what their threshold will be for taking action, or how much warning they will give to the US Air Force."

-Why doesnt everybody love google like otto does?

Jun 04, 2019
CLOUD CUCKOO LAND OF SPACE BUNNIES

There is no collision avoidance
Musk has to get real
Face it
Musk cannot keep putting up satellites
This cloud cuckoo land of satellites
As it's not just Musk
There's all the 1000s of copycat Musk's putting up their own 12000 satellites
Soon this earth will be a sea of colliding satellites
Billions of trillions of colliding shards
These Space Bunnies
In this Space Station
Are going to be hungry Bunnies
Whoever is financing Musk
Is in for a financial fall
Unless this is all Musk's money
One fine day
NASA is going to step in and put a stop to this
There are rules
You Cannot Keep Putting Satellites In Earth's Orbit

Jun 04, 2019
Musk is a menace. As long as satellites use solar panels for power, they will be highly reflective. Right now, 1/3 of ALL astronomy images are compromised by satellite tracks. If this jack--- has his way, ALL of them will. Way to ruin a scientific discipline.


Just genius. Amazing. Yeah, the guy putting lots of satellites up will ruin astronomy. Not like there's any way to put telescopes in space.

Also, going to point out that Kessler syndrome is way overblown. Don't get me wrong, Musk is insane and I wouldn't want to actually meet him, but the actual stuff he's doing is not bad.

Jun 05, 2019
Kessler syndrome is way overblown


It doesn't take much when the relative velocity of the particles flying around is 7 km/second. A single loose washer goes right through a satellite with enough kinetic energy to make metal evaporate - it explodes on impact.

Space is big, but if your satellite blows up into a million pieces, it suddenly becomes very very small since you can't track all those objects for collision avoidance for the other 7,499 satellites on the same orbital shell. Sooner or later you'll get another hit, then more debris, then another hit...

Of course it works as long as you can avoid the first impact, but putting so many satellites on such a tight constellation on a low orbit around the earth is setting up a scenario for the satellite equivalent of uncontrolled fission.

Jun 05, 2019
but the actual stuff he's doing is not bad.


Musk employs what he calls first principles engineering - that means taking things at their conceptual face values, selling that to the public, and then demanding the actual engineers to make it happen. If they can't make it happen, he either shifts the goalposts, or makes a bigger announcement to hide the fact that he couldn't reach the first goal, or both.

That means his plans always have huge caveats. He is essentially saying that if you take a square peg which has a cross-section area of A, and a round hole which has an area of A, then the two should fit together because A = A. The rest is just technical details that the engineers can surely work out. In any case, he's already secured the funding to fit a square peg in a round hole. After a couple years, his company will release a square peg that fits the round hole by cutting off the corners.

Is it still square? Why of course, it has four parallel sides...

Jun 05, 2019
I suppose you have done a better job launching and landing reusable rockets?

Jun 06, 2019
if you place a small explosive in each and detonate them at once, it creates a dense shell of debris
"LGM Minuteman 30 approximately 15,000 mph (Mach 23 or 24,000 kph) at burnout"

"The regulatory commission approved SpaceX's proposal Friday to fly more than 1,500 of its Starlink satellites at an altitude of 341 miles, or 550 kilometers, instead of the 714-mile-high (1,150-kilometer) orbit originally planned."

-Apogee of a typical ICBM is 1500/2500mi. And space is very, very big. Transit time through your shell would be a fraction of a second with little chance of hitting anything.

Jun 06, 2019
MUSK Immortalised
Eikka> Musk employs what he calls first principles engineering that means taking things at their conceptual face values selling that to the public then demanding the actual engineers to make it happen If they can't make it happen he either shifts the goalposts or makes a bigger announcement to hide the fact that he couldn't reach the first goal, or both.
That means his plans always have huge caveats is essentially saying if you take a square peg which has a cross-section area of A, and a round hole which has an area of A, then the two should fit together because A = A The rest is just technical details that the engineers can surely work out In any case, he's already secured the funding to fit a square peg in a round hole After a couple years, his company will release a square peg that fits the round hole by cutting off the corner

When that impossible dream fails in its reality
There's always Musk

Is it still square? Why of course, it has four parallel sides

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