What does it it do and what is it for?

Aria 1 is a habitation module designed for long term stays or a module for making bases on celestial bodies.

Stages

Stage 1

At stage 1 three liquid fuel boosters and 1 liquid fuel engine ignites, the boosters are uniquely attached and the way they are connected makes it impossible to separate them, but stage 1 can carry you almost exactly outside Droo’s sphere of influence.

Stage 2 and Stage 3

Stage 2 separates stage 1. Stage 3 is an engine which can blast you over 30 kilometers per second, it is capable of going to your heart’s desire and even go to multiple bodies without staging. Make sure to not retract the solar panels as the battery supply is very tiny and not reliable unless all the lights are off.

Stage 4 and stage 5

Stage 4 removes stage 3. Stage 5 is an engine which is usually used for making small burns to change it’s orbit significantly or make little burns to rendezvous with something on the surface. Stage 5 is not designed for changing it’s orbit around the sun or decelerating into a planet, trying is irrelevant.

Stage 6

Stage 6 removes stage 5 and activates 4 engines which are designed to make the habitat descend onto the surface, you have to use the activation groups to deploy the parachute.

Stage 7

Stage 7 removes the 4 engines, you must be very careful with the stage and remember to do a quick save right before you activate the stage. You must change the time mode to paused and set throttle to 100% and activate the stage, then turn the time mode to normal or slow motion depending on how careful you are.

This is the enhanced version of the original Aria 1, you can view the old one here

Avoid landing on a slope, the habitat can easily roll down a hill