
Fuzzypaws |

Actions aren't purely mental unless explicitly stated so, and pretty much the only actions in the RAW that are purely mental are purely mental skill checks (perception, etc). Even "psions" in most settings still need to make gestures to help focus their minds / guide the synaptic pathways in their brains.

whew |
Unless "mental" is the same as "purely mental", there are no actions in the CRB that are explicitly stated to be "purely mental".
Supernova doesn't require that the user have a free hand/appendage. Therefore, gestures must not be required to use it.
If we're looking at other settings for guidance, in Pathfinder, occult spells and spell-like and supernatural abilities don't require gestures.

Gilfalas |

If your Solarian gets paralyzed, can he still "explode" with the supernova ability?
I am going to go the total opposite of everyone else in this thread and say yes they can.
Starfinder pretty explicitly states that there are no components or gestures required for using the vast majority of powers and spells in the game. So they way I read it an attuned Solarion, even paralyzed, only needs to decide to supernova and the power activates.
That to me seems like a purely mental action.
Just like someone could cast any spell in Pathfinder that had not V,S or M component while tied up or paralyzed.

Gilfalas |

Flagged for FAQ, because this will help get an answer for supernatural abilities in general. By Gilfalas's logic, a dragon could use their breath weapon even when paralyzed even though logic says otherwise, but they're right that there is actually no answer in RAW on the matter.
Actually I would think that a breath weapon from a dragon would have SOME physical involvement given it's nature with being BREATHED out. While a paralyzed creature can by definition still breath I think a breath WEAPON would be more than simple oxygenation alone and would fall under the physical action definition enough to be a no go.
Like a lot in this game a blanket statement probably will not cover every situation and a GM will have to make an informed decision for a lot of things.
But Solarion abilities seem, on large part, to be mental/spiritual focus and as such a mental action to activate. Of course there will be exceptions but the one asked about here seemed clear to me.
I do agree that perhaps an FAQ would be helpful.