Russian Satellites Have Been Jamming GPS Signals Across Europe, Scientists Say

They don't attempt to jam, the frequency is just little bit off to minimize damage and it's very short time. They just test the system to verify that it works.

What this reveals: Russian early warning satellite constellation has also GNSS jammers they test periodically. They can jam whole continent from single satellite. They have six satellites in Molniya orbits.

Other discussion: https://news.ycombinator.com/item?id=48409664 (128 comments)