L-4 is a specific orbit in the Earth-Moon system.

'Know our comms.'

COMMS?

"We are 4 days away from the first official launch of the @SpaceForceDoD! 45 WS has your L-4 forecast ready to go.

Launch day probability of violating launch weather constraints: 60%

Primary concern(s): Liftoff Winds, the Cumulus Cloud Rule, Disturbed Weather Rule"

8:28 AM - 30 Dec 2019

https://twitter.com/45thSpaceWing/status/1211685605282910208