Nate Heywood with assistance from Ray Palmer and Martin Stein constructed a device to help pinpoint the epicenter of time quakes in order to prevent temporal aberrations before they happen. While in the Waverider's library, Nate and Amaya witnessed the device working and it detected an aberration originating in December 7, 1987 during the United States (Earth One)' and Soviet Union's negotiations surrounding the INF Treaty.
DC's Legends of Tomorrow
Behind the scenes
- In "Outlaw Country", Ray Palmer refers to the time seismograph as Trouble Alert. This is a reference to the Troubalert, an emergency monitoring system from the DC Comics that relayed information from the Justice League Satellite to the Hall of Justice.