Finding a way to “listen to the Emergency Transmission 02” is an objective for the Back to Vectera mission in Starfield.
You return to the mining planet from the tutorial section to track down Barret who is later revealed to be captured by the Crimson Fleet.
Your search then leads to the planet Gryphus where Garret crashed his ship. Luckily, he is not among the rubble.
You, however, do find a severely wounded Heller who quickly hands you the Emergency Transmission disk. Starfield does not explain how you are supposed to use the disk to listen to the Emergency Transmission. Luckily, the solution is easier than you think.
How to listen to Emergency Transmission 02 in Starfield
Once you obtain the Emergency Transmission disk from Heller, you might think that you are supposed to take it to a radio tower or some other location to be able to pick up the transmission.
However, you only need to open your inventory and click on the Emergency Transmission disk. It turns out that this was not an active transmission, as in a transmission that is being broadcast live. It is an audio tape.
Interacting with Heller’s disk in your inventory is going to play the disk and enable you to listen to Emergency Transmission 02 in Starfield.
Note that you will find the disk under your Notes. Search for it in the list (you are likely going to have a lot of notes) and click on it.
Once you have heard the complete transmission, head over to the planet Bessel 111 and fight off some of the Crimson Fleet gang members to free Barrett.
Return to the Lodge
All that is left to do is return to the Lodge in Jemison and speak with Garrett to complete the Back to Vectera story mission in Starfield.