Events I cannot explain

Question

In the last few days I experienced two events I cannot explain. I watch the sky since I was a child so I'm aware of most events like satellites, ISS, Iridium flares, etc...

First event

It was about 22:30 local time and I was located in the central Italy. I was looking in the nearby of Hercules and Corona Borealis when some degrees at left of Arturo (say near M5) a white light flashed shortly. The flash was very short, I think below 150 ms without any fade. Because it was so short I cannot say if it was moving or not, but the other strange thing is it's apparent diameter. It was larger than any other star or planet and without any difference of luminosity between the center and the border. I mean, it was like a small disk with a matte surface and a uniform white light. I can estimate it's magnitude about -2 (slightly less Jupiter in these days). It was not like an Iridium flare at all.

Second event

Yesteday, norther Italy, 1:30 AM local time. I saw what looked like a very bright satellite in SW/NE orbit. But there were few strange things:

1. as far as I know, it was too late for any satellite to be illuminated by the sun for such a bright magnitude. It was as bright as Venus at its maximum brightness (I would say at least -3.5).

2. it was composed of two distinct lights, very close together. At first I thought it was a plane from the nearby airport with landing lights still on after takeoff, but I know them and this was different. Furthermore there were no red/green lights nor strobo. And the lights were too close for a a plane below 10000 feet. Then they didn't change their brightness across the sky, like landing lights do.

3. it moved across the sky like the ISS does, and just few degrees from my zenith it disappeared instantly without any fading.

Any idea of what they might be?

Answer 1

Both of these sound like satellites reflecting the Sun, even the first one which didn't fade. There are so many satellites now with unusual orbits that being close to midnight in time doesn't mean you won't see them anymore like it used to. Years ago, if the local time was midnight you could almost be assured no satellites would be visible but that's not the case now.

I think your second event was also a satellite, or more specifically a pair of satellites. Since they vanished near your zenith at that time of the night, my guess would be they entered the Earth's shadow. Polar orbiting satellites can catch the Sun at unusual times due to the geometry as can a multitude of the new sats being launched constantly.

I forgot to add the the first one you saw, somewhat near M5, would be in the right position for that one to have been a geostationary sat (perhaps tumbling) but it also could have been another type, as well.

Answer 2

As @AstroShannon said, these are all satellites. The nightsky is being lost. Even satellites in geostationary orbits are well visible for astrophotography because they are near the ecliptic where much of the interesting stuff lies, and they haven't heard about "distancing" ...

Visibilty of a specific satellite depends on your position and the satellites orbit and height. For instance, when you're high up in the north and the satellite is a high inclination orbit passing over you it may well be visible during the whole night, even more so during summer. And it is likely not the only one. Imagine, the satellite was positioned so as to have the northern hemisphere in view as long as possible. These are the space nation's spyware stuff, but of course also useful civil earth observation.

Additionally, there's an increasing number of "internet for everyone" providers, and they quite openly care little about side effects. A discussion of just one constellation states that

[...] However, at low elevations near twilight at intermediate latitudes (45-55 deg, e.g. much of Europe) hundreds of satellites may be visible at once to naked-eye observers at dark sites.

The Low Earth Orbit Satellite Population and Impacts of the SpaceX Starlink Constellation

Hope that explains the observations.