This is a topic of great interest to me, especially since Voyager 1 is the most remote craft we have ever sent forth.

After 40 years of travel, it has reached the light distance of only 20 hours. In evaluating this result, it tends to place a large damper on our ultimate ability to reach anywhere that is significantly outside the solar system.

This graphic (which represents a logarithmic scale, based on AU) was created in 2013, and so Voyager is ever so slightly more to the right. Voyager is estimated to reach the Oort cloud in about 300 more years.

It will be many generations of us to come and go, before Voyager, then dark and cold, reaches the Proxima Centauri or Alpha Centauri neighborhood.

We have to work on the next generation (or two) of propulsion, otherwise we are restricted to the Solar System.

Update: As of 2 March 2021, Voyager 1 has traveled a distance of 21 light hours 5 light minutes and 35 light seconds away from the Earth; its velocity (with respect to the Sun) is 38,026.77 miles per hour (16.995 km/s).

This (the white circle) is where Voyager 1 is now, courtesy of the New Horizons spacecraft, which itself is 50 AU from Earth. Courtesy of NASA