Empty Space

Most working star maps show only those systems suitable for human colonisation. As anyone can see, these are not the only stars in human space - each 5 parsec map hex is far from empty - containing, as it does, between 25 and 50 other stars (there are approx. 5000 stars within 30 parsecs of Sol). Most of these lack planets - and those with planets are unsuitable due to a dangerously active star, it being a binary system, or having an uneconomically large M25 limit (generally anything over about 35 au). All these stars have been visited by human ships and are surveyed periodically by survey ships of various polities to check for unstability, or risk of nova or supernova.

Download list of stars near to Sol http://www.theuniverse.org.uk/astrography/starsurvey.rtf