The Leonov, built in 1988, carries both signals-collection and sonar sensors—including hull-mounted arrays and a “dipping” sonar to get below thermal layers in ocean waters. So its proximity to Groton is likely an effort to collect data on the comings and goings of submarines home-ported there and also to intercept communications to submarines as they enter and leave port to better identify them electronically. The ship’s large dome shields a satellite communications antenna for transmitting signals intelligence back to Russia.
Sooner or later the endless spectacle is over. Then we will take revenge. Mercilessly. -Alexander Dugin