I used http://me.cmdr2.org/starlink/#1522 to get a rough time for when the Starlink production test satellites would fly over Northampton UK
Sunday 26/27 May around midnight
I Was surprised to see how clearly they were going over Northampton UK at midnight, at one point they shone very brightly more than the ISS just after twilight. Most were close together still, but a few at the end had much longer gaps between them. I was so happy to see them so clearly but it does concern me the effects it may have on ground based astronomy with 12,000 of them flying. I hope part of returning to the moon some far side telescopes are set up.
They flew right overhead, at one point I was looking directly up.
There was a large range of brightnesses, This would depend on their orientation especially with respect to the solar panel due to its large reflecting area with respect to the position of the sun.
They were very easy to see over Northampton just after Midnight, at their dimest they look like dim stars to the naked eye so as you cannot see the stars through clouds you will not see starlink satellites.
When I watched them last night at parts of their orbits flying over they were very bright, even more that the ISS which looks like a very bright star that is easily seen.
SpaceX Starlink Satellites Flying overhead
They fly over roughly every 90 minutes so you should be able to see them during the night in the UK as our position here is at a high latitude and the sun should be shining on them.
Note: The Starlink Satellites will be visible any time they are lit by the Sun, which in some cases will be all night due to high inclination, high latitude of observer, and axial tilt of the planet.
UPDATE: The following days the satellites quickly began separating out along their orbital path, there has been a very marked decrease in their brightness as they increased their altitude. My latest sighting was just of a single fairly bright satellite less brighter than the ISS.
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