Clues:
r(t)=e(đťť…t/4)
- t1 = 0
- t2 = 8 ln(3)/đťť…
- t3 = 2.0492
- t4 = II . IV VII VII VI I
[contextual diagram]
Instructions: Name That Astronaut
_ _ _ _ A
Taking out my calculator, I find that all of the $r(t_i)$ numbers are close to integers, all within the 1-11 range that appears in the diagram.
So I think that the “astronaut” (or “cosmonaut”) you're looking for is:
LAIKA the dog, who was launched into space by the Soviets in 1957. Her name satisfies the letter pattern
[AL][AI][IK][AK]A
from the boxes connected to the numbers 1, 9, 5, 7 in the diagram.
The question title is:
a reference to Scooby-Doo, thus hinting at a dog. “Don't” may be a reference to the fact that Laika never returned from space, dying of overheating while in orbit.
OP Edit:
r(t4) is the number 2.47761 in roman numerals