Approximately Up Achievements: All 22 Listed

Approximately Up ships with 22 Steam achievements, and every name and unlock condition below is transcribed from the live achievement list for app 3904850 — not summarised and not paraphrased. They double as the most reliable published list of what is in the game: six worlds, one black hole network, two live animals and a submarine all appear here before they appear anywhere else the developer has written.

Showing all 22

Tutorial & First Steps 3

The opening three. Baaa-ck To Headquarters is the one people miss, because it asks you to bring the tutorial sheep back rather than just finish the flight.

AchievementHow to unlock
Tutorial Completed Successfully complete the tutorial.
First Milestone Complete your first objective.
Baaa-ck To Headquarters Bring tutorial sheep to Headquarters.

Exploration 6

Six achievements that are really a map in disguise. Two of them name worlds — Tenebra as the farthest known planet, and the Black Hole Tunnel as a route to an entirely different universe — which tells you more about the shape of the star system than the store page does.

AchievementHow to unlock
One Step Further Discover a new planet.
Solar Storm Encounter a solar storm.
Way Forward Activate a Black Hole Tunnel.
Jurassic Surprise Encounter a dinosaur.
Event Horizon Travel through a Black Hole Tunnel to a new universe.
Edge Of The Known Find Tenebra, the farthest known planet.

Depth & Pressure 2

The underwater layer. A submarine build is a different problem from a spaceship: you need to survive going down rather than up, and Green Trench wants the bottom of it.

AchievementHow to unlock
Houston, We Have A Submarine Reach a depth of 1000m below sea level.
Green Trench Reach bottom of Green Trench.

Live Cargo 2

A sheep from Earth to the Moon, and a mastodon from the Moon to Earth — both alive, and both released into the wild at the far end. These are the achievements that give the game its tone.

AchievementHow to unlock
Wool Age Transport a sheep from Earth to the Moon alive, then release her into the wild.
Ice Age Transport a mastodon from the Moon to Earth alive, then release him into the wild.

Speed & Extremes 4

Numbers you have to hit exactly: 1,000,000 m/s of speed, 1,000,000 metres from the Sun, 100,000 metres from the Red Dwarf. See You Next Week is the endurance version — a safe run between Aundara and Outcast in either direction.

AchievementHow to unlock
Need For Thrust Reach a speed of 1 000 000 m/s.
See You Next Week Travel safely from Aundara to Outcast, or from Outcast to Aundara.
Almost Crispy Get within 1 000 000 meters of the Sun and survive.
Small But Spicy Get within 100 000 meters of the Red Dwarf and survive.

Story & Completion 5

The campaign spine and the completionist tail. Golden Thruster is the hardest thing in the game: every objective, without ever using Time Rewind. Since patch 1.0.006 the Objectives Log shows a completion percentage, which is the closest thing to a progress bar for it.

AchievementHow to unlock
No Rewinds! Complete the objective without using Time Rewind.
Saving The Twins Prevent a planetary catastrophe.
The Long Way Home Complete the journey.
When The Thrusters Go Quiet Complete every available objective.
Golden Thruster Complete every objective without using Time Rewind.

Achievement list checked against Steam:

Several of these are really location problems. The planets page covers where Tenebra, Aundara and Green Trench sit, and missions lists the named objectives that Golden Thruster and When The Thrusters Go Quiet both require you to clear.