OT: Thanks to whoever posted the link to Starlink

[nothanks]

A quick THANKS to whoever posted a link to the Starlink tracking website

a short time ago. I used it to predict when they might be visible and it was an amazing sight, just now, to watch the line of about 60 satellites track across the sky. I wonder what people who don't know about Starlink think is happening when they see them. From a a quick google: SpaceX have approval to launch 12,000(!) satellites and have applied for approval for a further 30,000 (yikes!). Supposedly the satellites will become less visible when they've moved to the planned orbital height.

[Andy Burns]

That was me, there's another site that uses google streetview imagery to show you where to look, here's links or both the starlink "trains"

Works well on mobile browsers with location enabled

I think the first two sets of 60 are at their final altitude, presumably you saw the "starlink2" train tonight, they're not yet in position.

[nothanks]

Yes, according to the tracking website it was the "train" from the recent launch. Interestingly, there seemed to be a gap in the "train" and Mr Google tells me that one of the latest batch has a coating to reduce its visibility - I didn't count to see where the gap was, but it seems likely that the coating works!

(Well done for using "altitude", as an aviator it's slightly embarrassing that I used the term "height" :-( )

[Brian Gaff (Sofa 2)]

Ah but if one becomes faulty and drifts int the next one do we have a very large game of asteroids on our hands with debris making getting part themhard. Brian

[Andy Burns]

They're not evenly spaced yet, when they launch them they effectively just pull the pin holding all 60 in place and let them drift away, from there they manoeuvre them, the animation for me shows some of them overtaking others to get into position.

[Andy Burns]

They apparently have active collision avoidance (one of the things making tracking them precisely more difficult as they are autonomous).

I think they already have 3 dead ones that will get de-orbited.

[Brian Gaff (Sofa 2)]

Yes and if the so called automatic fault detector goes faulty. I am afraid this kind of thing worries me as we could very quickly find we have no way safely off the planet due to debris. Add to this the RF pollution and the reflective effects on ground based astronomy and to me you have a complete c*ck up. Brian

[nothanks]

They are in a low orbit so will decay naturally if the thruster or other systems fail, it will just take longer. I agree that, with such a huge number of satellites, it would be disastrous if the autonomous anti-collision system failed.

[Andy Burns]

Astronomers might sue FCC for granting starlink's licence