In pursuit of Venus
Roughly 1,500 people turned out to view the transit of Venus, the last one of the 21st century. The public viewing was hosted by the Department of Earth and Space Sciences and the graduate student group Astronomy Live!.
Roughly 1,500 people formed long lines Tuesday on Janss Terrace to get a glimpse of an astronomical phenomenon that won’t happen again until 2117.
For them, the wait to get a good look at the second and last transit of Venus of the 21st century was well worth it, thanks to telescopes and other solar sight devices manned by knowledgeable members of the Department of Earth and Space Sciences
and graduate students with the campus organization, Astronomy Live!
During the public viewing, the relatively cloudless skies gave the campus community as well as visitors a clear sighting of our neighboring planet as it passed between the Earth and the sun. Venus was easily viewable from Earth as a black dot moving almost imperceptibly across the solar surface.
The transit of Venus was also visible to the naked eye, at least to a naked eye protected by solar glasses (staring directly at the sun can harm the eyes — just ask Sir Isaac Newton, who famously injured his eyesight while observing the Sun from a darkened room).
Photo by Tyler Adamczyk.
"It's amazing to be able to catch it,” said UCLA senior Robin Mohammed, who happened to be passing by when he decided to join the gathering crowd. “I am proud of this. If I hear that something this rare is happening, I’ll definitely check it out.”
Other students were also fascinated by the view.
Junior Caitlin Leyden saw the event on the campus calendar and came by because "astronomy is always interesting," she said.
Postdoctoral scholar Bin Yang, who is visiting from the University of Hawai’i, was delighted by local interest in the event. “There were so many people asking interesting questions. And you could see Venus really clearly through the H-alpha telescope,” Yang said. The hydrogen-alpha telescope has a special design that allows observers to see only certain wavelengths of light emitted by hydrogen, making Venus especially clear.
In the 18th century, the transit of Venus was particularly important because scientists could use it to calculate the distance between the Earth and the sun, the fundamental yardstick used to measure the size of the universe.
It didn't require sophisticated devices to monitor Venus as it made its way across the sun.
Expeditions were organized around the world to view the 1769 transit. Viewers were asked to report their location and the exact time of the interior ingress, the moment when Venus is first wholly inside the solar disk. The data were collected and used to calculate what is known as the astronomical unit, the distance between the Earth and the sun. Of course, that measurement is now known with much greater precision: 149,597,870.691 kilometers (92,955,807.273 miles).
In an updated version of this experiment, many of those gathered on Janss Terrace were trying to submit measurements of the interior ingress through an app installed on their iPhone or Android. The data would then be transmitted to global database just as occurred in the 18th century. But ESS Professor Kevin McKeegan reported with frustration that there were so many people trying to upload data that the website crashed.
To highlight the historical importance of the last transit of Venus likely to be seen by any living person, UCLA librarians brought out a display case of books that discussed the transit. The display included children’s books and even the score of John Philip Sousa's "Transit of Venus March," which was playing to mark the occasion.