"Engineer, prepare for take-off," said Commander Addie.

"Yes sir," Engineer Liam said. "Where are we going?"

Addie punched buttons and flipped switches. "Destination: the asteroid belt where we must rendez-vous—"

"Ron-day-what?"

"Where we must meet the Mother Ship."

"What's an asteroid belt?" Liam asked. "I've got a tool belt." He patted the strap that held wrenches and hammers.

Addie pointed to the 3-D solar system chart overhead, hanging from the cockpit roof. "There's the sun, in the middle. Two little planets come next. Then there's Earth, which we're near. Going further out, there's Mars, then a whole bunch of asteroid rocks doing a big circle dance in a ring around the sun."

"Cool!" Liam said. "And more planets after that. Wow!"

"At the Mother Ship we're supposed to get a passenger to bring back to Earth orbit."

"Is our interplantiny, um, interplantery—"

"Interplanetary," said the Commander.

"Is our in-ter-plan-et-ary rocket big enough for three?" Liam looked around at their cramped quarters.

"Yes. It's a small passenger. We have just enough room."

Engineer Liam punched a button and yelled, "Lift off!"

They took off so fast, Addie and Liam had to hold on tight. Addie watched the lights blink on the control panel. "Alright," she said, "we have reached top speed. We're zooming faster than a meteor."

"Engines off," Liam said, and punched another button. "Now we'll drift the rest of the way, faster than a, um—"

"Meteor."

"Yeah."

"No gravity!" said Addie, bobbing around inside the rocket.

Liam turned upside down, head over heels, laughing and laughing.

An alarm started beeping.

"Oh no!" shouted Commander Addie. "Something is coming at us!"

"Another rocket from Earth?" asked Liam, trying to get right-side up.

"No! It's a flying saucer from Mars! Quick, turn on the emergency motor!"

Liam punched buttons and pulled a lever. "Ba-room!" he yelled.

"Oh no!" shouted Commander Addie. "We got away, but now we're spinning out of control. Turn on the stop-spinning thing."

"Yes sir," said Liam. "There. Trouble all over."

"Whoosh!" said Addie. "That was close!"

"Are we there yet?"

"Almost," said Commander Addie. "First we have to dodge all these asteroids. Look out!"

They swayed left. They swayed right. They turned upside down and zoomed up and down and around. Finally they came out into the open.

"Look," Addie said, pointing ahead. "There's the Mother Ship. Prepare for docking."

"We're already talking," said Liam.

"Docking," Addie said. "Grabbing onto a landing spot. Not just bumping and bouncing away."

"Oh. Right," said the engineer.

Klunk!

The radio buzzed. "Are you ready for your passenger?" asked a Mother Ship voice.

"Yes," Addie said. "Open the hatch, Engineer Liam."

He did. A passenger pod slid into the rocket ship and settled into place. There was just enough room.

The Mother Ship voice said, "Your mission: Fly back to Earth orbit without bumps or thumps, but don't let the Martians kidnap the passenger."

"Yes sir!" Addie said.

"We'll go soft and slow," said Liam. Then he whispered, "Lift off!"

The rocket wiggled (just a little bit) as they took off.

"I'm steering a longer way home," said Addie, "so we don't have to dodge asteroids."

They spent the time as they swooped gently along by spinning the 3-D solar system chart, just for fun, and shining a ray gun out the rocket window, and singing a rocket song.

"This really is a longer flight," said Liam. "Who's hungry?"

The passenger waved her arms and gurgled.

Liam sang, "Magic Box, we'd like to feed. What kind of food does our passenger need?" He opened his Magic Box and took out an astronaut meal tube with a sippy nozzle.

"I'll feed the passenger," said Commander Addie. "You keep a watch out for flying saucers."

"Good idea," said Liam. "In Engineer School, they didn't teach us passenger feeding."

The passenger made funny noises and waved her arms again.

"I don't know what language she's speaking," said Commander Addie, "but I think we're getting along okay."

"Oh no!" Liam almost yelled it, but remembered just in time to keep a low voice. "Here comes a flying saucer! It has a glass bubble on top. We can see inside it. Eek!"

Addie looked. Inside she saw a violet blob that had three hands waving around. Each hand had six fingers. "It has three eyes!" she cried, almost too loudly. She punched at the rocket ship controls. They gently zigged and softly zagged, but could not get away from the flying saucer.

The radio made crackly noises. "I've got you now, Earthlings!" buzzed the violet Martian's voice. Its eyes bobbed around on eye stalks. It waved a 6-fingered hand. "I'm going to take your Magic Box and that delicious-looking passenger."

Liam wrapped his arms around the passenger pod. "You can't have her!" he said. "Take my Magic Box and go away!"

"Oh Liam!" said Addie. "Such a brave and unselfish thing to do! But there must be a way to make the Martian leave without us getting robbed." She tried shining the ray gun at the flying saucer, but the violet Martian just opened its mouth wide and laughed. It had three tongues!

Liam groaned. "Now what?"

The passenger waved her arms as if saying, "I have an idea!" but she didn't say anything that Addie or Liam could understand. Instead, she let out a high piercing shriek!

The Martian's eyes went all big and googly. It clamped its 6-fingered hands over its tiny ear-holes, and its mouth made a squiggly zigzag line. "Eep!" it squealed. The flying saucer zipped away, back to Mars.

"Yay!" said Liam.

"You can stop shrieking now," Addie told the passenger. "The Martian is gone."

The passenger kept shrieking.

Addie looked at Liam. "That will keep the Martians away while we finish our journey back to Earth."

"Yes, I guess so," said Liam, scooting away from the noisy passenger. "Are we there yet?"

"Here we are, back at Earth orbit," said Addie, "and here's the Father Ship. Docking!"

Bump!

Daddy lifted baby Lucy, carry seat and all, from Addie's Magic Box. "Good job, Commander," he told Addie. "Good job, Engineer. You two did great on your first passenger mission! And good job, Little Lucy. The whole neighborhood is safe now from Martians and flying saucers."

Addie and Liam jumped out of the rocket. They pushed Addie's Magic Box back to Box Corner. They gathered up the flashlight and the belt of plastic tools and put them in Mommy's Magic Box.

"Keep the solar system mobile out," said Mommy from the couch. "We'll hang it above the crib."

"Good!" Addie said with a grin. "Lucy can start learning all about the planets! Then one day she'll know how to be rocket ship commander, too."

Addie and Liam joined Mommy and Daddy on the couch, where Lucy made sure they all stayed safe from Martians.