I found out that the Survey A Planet mission icon (sometimes) centres on a ‘wild’ base computer, (where you can claim a habitat).
You need to be quite precise as you fly in, to ensure you don’t lose your pinpointed location because the icon fades once you enter the atmosphere.
This means, (provided it hasn’t been nerfed), that a shared portal address & co ordinates of this location, could enable a portal traveler to relocate close to your location if multiplayer isn’t a viable option.
I haven’t tested this but it used to work this way.
Another thing I’ve noticed, is that the mission for Survey a Planet centres around a particular area: This means all 3 Hotspots will be within about 10 minutes walk of each other.
I noted that if you leave this area, the hotspot icon in the scanner will not light up, meaning you are out of the search area.
(I’m not sure if the same ‘area rule’ applies to the scanning of creatures but it’s worth remembering if you are struggling).
Moving closer to the previous Hotspot finds, reinstates the search icon.
Just thought I’d share these couple of points.