Something Can Be Real Without Being Available From Here
Visibility depends on conditions. A night sky can contain objects hidden by daylight. An aurora can exist beyond the place from which we are looking. A signal can be present outside the range of the instrument we are using. Not available from here is not always the same as not there.
The distinction becomes useful beyond astronomy. A person may lack the language for something they are already experiencing. A possibility may be invisible from inside the assumptions that currently organize a problem. A pattern may become obvious only after enough distance has been created to see it.
This should not become an excuse to assert invisible things without evidence. Unseen is not proof of existence either. The point is epistemic modesty. Our vantage point helps determine what is available to us.
Sometimes the right response to not seeing something is to conclude that it is absent. Sometimes it is to change position, method, timing, or instrument and look again. Reality is not required to be visible from every location at every moment.