When does twilight arrive?

The sun has risen at McMurdo, we're 800 miles away that station and I was curious as to when twilight will reach us. I began digging around Google and found an ex-Polies blog:


Keith describes life at Pole is 100% right on. I went to his August posts and my question was answered... twilight has begun and within a few days would should be able to see the first glimmer of light. Well, that realization just killed my curiosity and now I feel rather excited that change is on the horizon.
Astronomical twilight began on August 1st, and the sun doesn't rise until the equinox around Sept. 23.