According to the Old Farmer's Almanac website www.almanac.com sunset at Poynette Wisconsin on April 26, 1970 was...7:54 pm CST! So um, they finished before the sunset. It's possible the sun was starting to behind some trees or hills or something so was below the visible horizon at the concert location but had not yet "officially" set.
Iver > Re: Length of Poynette 4/26/70 Dark Star. > I was there that day, just as the sun was hitting the horizon Phil > announced: "Now we're gonna do a Sunset Raga." They > finished playing at > 7:30, so if you dig out an almanac and find the time of > sunset on that date, > you get the length of the Dark Star. > If someone actually does this, please post the result, as I > don't remember. > Ron > Santa Fe >