Deliberate mistake: Captain Haddock finds out the SOS was a fake so he tells the engine room to increase speed. Just after they increase speed and Tintin says "The people financing the Peary", we can tell the boat isn't moving since the background is entirely still and not moving an inch. (00:14:45)
Continuity mistake: There is a shot of the meteorite and Tintin jumping onto it. In this shot he is approaching 4 meters away from the meteorite. Yet in the shot after a crew member of Peary yells "Pull, pull", Tintin is then seen approaching 4 meters to the meteorite a second time. (00:16:00)

Continuity mistake: When the huge apples fall off the tree, half of them are red and half of them are maroon. As the apples fall on the ground in the next shot, all of the apples are red. (00:18:20)

Continuity mistake: The huge apple that crushes the huge spider changes size between shots. (00:18:55)
Continuity mistake: The pilot goes onto a raft and looks at Tintin at a 12 o'clock direction saying "I can't get any closer". In the next shot, he's looking at Tintin in a 3 o'clock direction. (00:19:20)
Audio problem: Tintin places part of the meteorite on the raft. When it lands, it makes a sound as if it landed on a wooden floor. The raft is made of plastic and has air in it. Not the landing sound you'd expect. (00:20:15)
Continuity mistake: When Haddock says "There they are" after the rescue, he is standing next to Professor Fossil and they are both standing at the end of the ship. As everyone starts cheering, they are standing somewhere near the middle of the ship and a scientist has suddenly appeared next to them. (00:20:30)
Character mistake: When the plane returns, the "F.E.R.S" sign on the side of the plane has changed to a "R.E.R.S" sign. (00:20:40)
Chosen answer: It is a pill that makes alcohol taste disgusting.