Each space analysis Order Field tree is unique to the space field that you are in. This means that Space/M01 will have a different tree than Space/M02, etc. Choices made in the Order Field tree will be saved until it is reset.
If you make a mistake or like to try something different from the Order Field tree, you can reset it for free every 48 hours, or pay up to 50 to reset immediately. To reset the tree, send all your Factions fleets home to Eden and then select the reset button. The tree will be cleared and all the analysis points you spent will be refunded for you to distribute in the tree. Any clones created in the map, percentages of completion in exploration, colonization or mining, will not be impacted during reset.
When entering a new space field you don't have to worry about the 48 hour limit the first time you reset.
For Asteroid Exploration Analysis, asteroids are the named planetoids (not the homeworld).