Another PHM headcanon, a movie-specific one:
In the movie, when Grace notices the Blip-C approaching at a slower speed than the Blip-B, he concludes, “They [whoever’s on the Blip-A] think I’m dumb.”
I like to believe that Rocky’s interpretation of this - of the Blip-B being allowed to bounce harmlessly off the Hail Mary’s outer hull and float away - was actually the opposite.
Rocky had no way of knowing what resources or abilities the Hail Mary and its crew possessed. He might have initially guessed that the other ship had hull-bots similar to the Blip-A’s, which could be used to catch an object and bring it inside the main vessel for closer study. But he’d already observed the Hail Mary attempting to flee from him; he could predict that the alien crew might be wary, hesitant to accept any contact.
So he tossed over an object, small enough to (hopefully) seem non-threatening while large enough (hopefully) for the other ship’s instruments to detect its approach. (I kind of wonder if the Blip-B and Blip-C were constructed to be a specific small percentage of the Hail Mary’s total volume, to try and hit that sweet spot of small-enough-not-to-scare + big-enough-to-notice.)
At that point, *maybe* this smaller ship might’ve used a hull-bot to catch the Blip-B. But Rocky must’ve been pretty sure that the alien ship’s crew was uncertain of the Blip-A’s intentions. A hull-bot (or the interior of the ship, and its crew too) would be much more fragile, more difficult to repair when damaged, if the Blip-B (intentionally or otherwise) caused it any harm. The outer hull of the ship, on the other hand, would likely be the sturdiest part of the vessel, with the possible exception of the outer bits of the spin drive engines.
Letting the Blip-B follow its original intended trajectory with no interference was the Hail Mary’s safest, least risky, and smartest option. Rocky might have even thrown the Blip-B expecting that this first toss would be carefully observed but not yet accepted. I think if Rocky had seriously hoped and expected the Hail Mary’s crew to take and open the Blip-B, he would’ve thrown that one slower to start with. We never saw inside the Blip-B; we don’t know if Rocky even put anything in there.
When Rocky observed that the Hail Mary’s crew had (presumably) used the Blip-B as a test case, concluded that the Blip-A wasn’t throwing anything overtly harmful, and only then tried to retrieve the Blip-C — I think Rocky would’ve taken all that as tentative evidence that the smaller alien ship was not only crewed by living beings, but by living, intelligent beings… ones who might be smart enough to help Rocky and un-doom the Blip-A’s mission.
