The Gravity on Mars (Planetary Crossings Part II)

In keeping with the previous entry, the following has been edited for Kepler-186f and the likely gravity of the same has been factored in.

Two Keplerians and two Earthlings traveling together came to a canal. As a result of the gravity on Kepler, the Earthlings each weighed 200 pounds and the Keplerians 100 pounds. The watercraft would hold no more than 200 pounds. How did they all cross the canal?

(Source: Fantastic Book of Logic Puzzles by Muriel Mandell, illustrated by Elise Chanowitz)

This one requires more steps than the former but isn't too hard.

To begin with, sending over an Earthling is a non-starter because it will just mean coming back. So is sending just one Keplerian, for much the same reason. They both have to go over. In the next step, sending both Keplerians back is just ending up where you started, so send one back. The boat will then be able to carry an Earthling over to the far side. At this point, there is a Keplerian and an Earthling on either side of the canal. Sending an Earthling back will get nowhere, so send back a Keplerian. Now, both Keplerians and an Earthling are on the near side. Sending the Earthling back will not achieve anything, but it was useful for both Keplerians to be on the far side earlier, so send them to the far side once more. After the previous move, now only one Earthling is on the near side. Send back the boat with only one Keplerian, then let the Earthling cross. Finally, both Earthlings are on the far side. Send the far side Keplerian back to the near side and bring the both of them back over. This completes the crossing.