Captain Lancaster speaks to the Space Force team via. a teleconference, while traveling on a spaceship to Mars. He is about halfway to Mars at the time. At this distance, instantaneous synchronous conversation would not be possible. Although radio waves travel at the speed of light, at this distance, there would be a very noticeable delay between the time the message was receive on Earth, and the time that Lancaster received the reply on the spaceship.
The base psychiatrist's name appears on her door as "Lakshmi Miller", but the diploma on her bookshelf shows her name as "Marnie Miller".