Early Guide
Starting out
Once you have entered a map with The Stars Above mod installed you will be given a Spatial Disk. Upon interacting with the disk you will be greeted by the twin protagonists, Eridani (left) and Asphodene (right). You will have to choose between the two and once the decision is made depending on which side you choose, you will be granted the permanent effect 
or 
which will select which type of weapon you will be able to use. After doing the permanent decision to choose one of the starefarers you can use the Left-Click button to engage in small talk with the starfarer. But when Right-Clicking a menu will pop up with a few options, these are:
Stellar Array
The Stellar Array is a power given to you by your starfarer allowing you to activate certain abilities. There are 3 types of abilities from tier 1 to 3, the tier 1 abilities consume only 1 point from a total of 5, the tier 2 abilities consume 2 points, and the tier 3 consumes 3 points. The Stellar Array gives the player the option to change the damage that their held Aspected weapon will deal, the damage will be decreased by 10% if the damage type is changed.
Stellar Nova
The Stellar Nova is a special ability that is used by the Starfarer. here you can change the selected Stellar Nova. It can be activated by pressing the Stellar Nova key Z. Stellar Novas can only be activated upon gathering sufficient Stellar Nova Energy to fill the Nova Gauge. Stellar Nova energy accumulates gradually in combat at a rate of roughly 1/s. Defeating enemies has a chance to drop Starlight, which will give the player 5 Stellar Nova Energy automatically.
Astrolabe
The Astrolabe is used for traveling into the Subworlds. Upon interacting with this button, the Celestial Cartography map will appear which will show all locations which the player can visit. Each Subworld has a threat level, which can range from none to A-. For visiting a Subworld with a higher threat level the player will need to upgrade the Stellaglyph to a higher tier. Though for the visit of places with a threat level of none you can do it without a Stellaglyph. It should be noted that Subworlds do not work in multiplayer.
Archive
The Archive is used for the playback of messages and also to get back specific items like Essences or Mnemonic Traces and even boss summoning items.