The Atlanta Astronomy Club hosted a public viewing of the Transit of Venus on top of Stone Mountain last night. Around 100 people gathered to view this rarest of predictable events.
According to the Observing Chair of the Atlanta Astronomy Club Daniel Herron, the Transit of Venus is when Venus crosses between the Earth and the Sun. It runs on a 243 year cycle. The last time it was visible was 8 years ago. It will be visible again in 105 years, then 8 years after that, then 121 years later in a continuous cycle.
“It alternates in such a way that the next time it happens in 2117 it will happen in December,” he said. “The earliest astronomers used it to predict how big the sun was and how far the earth was from it by measuring the time it took Venus to enter from one side and exit the other. They could triangulate the position.
They did all this without computers!”
The Astronomy Club hosts events all across Atlanta and offers workshops in schools around town.
Marie Lott, a member of the Astronomy Club and of the Charlie Elliott branch, has been an amateur astronomer since she was 13.
“We've caught the International Space Station going across the sun,” she said. “You have to run to the right coordinates to be there.”
Lott brought a wide array of equipment with her to view the transit, including a dedicated solarscope, a refractor with a solar filter, a projection system and enough solar sunglasses for everyone in attendance.
There is a phenomenon among astronauts known as the Overview Effect. Author Frank White coined the term after documenting the experiences of astronauts, who experienced a paradigm shift up in space – they observed the earth, but not the lines that map out our individual countries. They suddenly, forcefully recognized that we are one race, one civilization and one community.
Atop Stone Mountain last night, as Venus began its transit of the sun at 6:03 p.m., a similar phenomenon was experienced. All of human civilization shared a moment in time and space that will not happen again until the next century.