Helping the astronaut, Maxwell needs to trade something for the martian samples and return them to the astronaut! First equip Maxwell with flying gears to jump over the gap.

Round 1: Flying Shoes
Round 2: Flying Shirt
Round 3: Flying Jacket
Give each martian: pearl, diamond, gold, emerald, silver, sapphire, ruby, gem, jade

Round 1: Pearl, Diamond, Gold
Round 2: Emerald, Silver, Sapphire
Round 3: Ruby, Gem, Jade

Pick up each of the samples and bring back to the astronaut.

Scribblenauts Remix 9-4 Cheats Hints gallery:
9-4-1-a: Trade something for the Martian samples and return them to the astronaut.
9-4-1-b: Martians like rare jewels.
9-4-1-c: Give them a diamond, ruby, and emerald.