Lock an object
In the planetarium mode
Locking an object in planetarium mode keeps it in the camera axis regardless of time and date. You can track an object even when you zoom in or out or accelerate/reduce time flow.
To lock an object, simply right-click on it with the mouse and choose the “lock on objet” option. To unlock later, you can do the same operation again by choosing the “unlock” option which appears in the context menu [1].