Exhibit A: Distance of stars from us, in light-years, and other information.
Exhibit B: definition of Light Cone.
Exhibit C:Your Personal Light Cone RSS feed.
"From the moment of my birth, light (that I could have influenced) has been expanding around the Earth and light (which could influence me, from an increasing distance of origin) reaching it -- this ever-growing sphere of potential causality is my light cone." My light cone has 61 stars in it. The next star to be reached is Beta Leonis, 4 months from now.
Hat-tip to james_nicoll.