[HN Gopher] Starlink satellites being lowered from 550 km to 480 km
       ___________________________________________________________________
        
       Starlink satellites being lowered from 550 km to 480 km
        
       Author : wmf
       Score  : 35 points
       Date   : 2026-01-01 19:58 UTC (3 hours ago)
        
 (HTM) web link (twitter.com)
 (TXT) w3m dump (twitter.com)
        
       | jagaerglad wrote:
       | So instead of having to launch new satellites to replace the
       | deorbited ones ever couple of years, do they have to send new
       | ones every couple of months? Or can the functioning ones maintain
       | their orbits somehow and this is only for the malfunctioning
       | ones?
        
         | lefra wrote:
         | They have an ion thruster to compensate for atmospheric drag.
        
           | m4rtink wrote:
           | There has been some research (IIRC by ESA) for using the
           | upper atmosphere to feed a ion engine. That way you should be
           | able to put satellites even lower as long as they have enough
           | power from solar panels and are functional.
        
         | manmal wrote:
         | They have ion thrusters that prevent them from losing altitude
         | as long as they are operational.
        
         | jws wrote:
         | It sounds like this corresponds to an atmospheric contraction.
         | They are lowering to avoid extending the lifetime of possible
         | debris, but that also probably means the regular lifetime is
         | not shortened. They are just staying in the designed density to
         | match their designed service lives. The field of view of the
         | satellites will be reduced, but presumably they have enough
         | units up there to maintain full coverage.
         | 
         | This is distinct from the FCC application they have made for
         | another Starlink shell in VLEO (~330km) for another 15000
         | satellites to better serve cellular phones.
        
           | verzali wrote:
           | At 480km there will be increased drag, even as we get closer
           | to the solar minimum. The trade-off may be between using
           | propellant for collision avoidance vs using it to counter
           | altitude loss and for station keeping.
           | 
           | Maybe it is also linked to the falling altitude of the ISS?
           | 480km is about the upper bound of its altitude but they seem
           | unlikely to actually raise it that high before it is
           | deorbited.
        
       | wmf wrote:
       | Usually orbits are reserved years in advance. AFAIK this kind of
       | move is unprecedented (although everything about Starlink is
       | unprecedented since it's the first megaconstellation).
       | 
       | Two weeks ago, a Starlink satellite exploded. SpaceX believes it
       | wasn't caused by a collision which means the explosion was
       | probably caused by a malfunction in the satellite itself. Now
       | 4,400 Starlink satellites are moving to a lower orbit for
       | "safety". Is this an emergency change to account for a design
       | flaw that they just discovered?
        
       | vipa123 wrote:
       | How much Delta-V would that take, and how much would they
       | typically have onboard at the start of their life?
        
       | GeertB wrote:
       | I wonder if this will improve latency and signal strength
        
       ___________________________________________________________________
       (page generated 2026-01-01 23:01 UTC)