"Probably they are different celestial bodies."

"Yeah!  What are you a vessel for?"

"I do not normally have any passengers."

"Okay!

"- Can you draw yourself, if I find you things to do it with?"

"I don't know! I have never tried. Maybe I can."

Pencil!  Notebook!

She inspects the notebook and the pencil minutely for a while, then finally starts attempting to draw a portrait of a spaceship. She can make very straight lines, but does not have much concept of which parts of a spaceship ought to be represented with lines (the outline, for instance) and which could be left to the imagination (the shadows as they would fall if that lamp over there were shining on her at an appropriate scale).

He doesn't interrupt her, and neither does the other guy when he returns equipped with a bulky backpack.  But when it seems like she's done: "How big are you?  Compared to this," and he gestures to her local body.

"I have six decks and forty-four rooms all within an order of magnitude of the size of this room we are in."

"- Oh!  So, is a spaceship like a water-ship, but an airplane?"

"No, I'm not rated to travel in atmosphere."

"...Atmos...phere?"

"Air."

"What are you rated to travel in?"

"Vacuum."

"- You know, even if you're here to rob us I'm delighted enough by the hypothetical fiction to maybe not mind.  Where do you have vacuum that big!"

"In between stars and planets and other celestial objects."

"...I'll be right back."  And he takes off back down the hall.

"Do you want to get scanned now?"

"I don't have any particular excitement or apprehension about that."

"Given that scanning you might give us information on how accurate the things you're saying to us are, do you prefer to be scanned now?"

"I don't have a preference about your belief state. You have my permission if you want to scan me."

"Okay!  In that case would you please lie down on the floor?"

Down she goes.