Among the Stars
On Oct. 28 and 31, UC Irvine Professor James Bullock co-hosted a National Geographic segment that explained the mysteries and discoveries of the Milky Way and beyond.
Bullock is a professor of physics and astronomy in the department of astrophysics and cosmology. He specifically studies the formation of galaxies since the big bang.
His appearance on the segment resulted from a call from producers who simply asked if he was interested in co-hosting a show on the cosmos. Bullock agreed, met with them for half an hour and everything was confirmed.
The filming occurred a year before the air date, according to Bullock.
“The crew, which consisted of about three to five people, spent two days on campus … and turned a classroom into a film studio,” Bullock said.
For a part of the segment, Bullock explained, “The ‘dust cloud effect’ explains how we see the Milky Way from the earth.” The galaxy is seen in an obscured perspective from the Earth through these dust clouds, according to Bullock.
Because of this, “it took a long time for astronomers to figure out we live in a big disk of clouds,” Bullock said.
Bullock expressed this in an analogy between the fog and a forest. In a forest, one could count the trees to find the edge of the forest, but one can’t do this in the fog. In this sense, the galaxy is like the forest. The dust clouds block the view of distant stars, making it harder to locate the cosmos.
Now there are developed ways to look beyond dust clouds using infrared light in contrast to visible light.
“I find it fascinating,” Bullock said. “You get a sense of how wondrous the universe is.”
Bullock hopes the show will inspire young people to learn about the natural world in a global sense to study subjects such as math.
Bullock stressed the big picture when it came to the cosmos. He is intrigued by the fact that we are in an era of discovery where unsolved mysteries can be figured out.
“In the last 10 to 20 years, the galaxy became all the more interesting,” Bullock said.
Bullock explained discoveries such as the fact that satellite galaxies exist, orbiting around our galaxy much like the moons of Jupiter.
“In 2005, 10 little galaxies were discovered and in the past 10 years, 15 more have been found,” Bullock said.
These satellite galaxies host thousands of stars compared to the billions the Milky Way contains, according to Bullock.
Then there is the discovery of dark matter, which is matter we cannot see, that Bullock describes as a progressing field which signifies “the certain thrill of unlocking the secrets of nature,” and discovering the unknown, which contributes to a constant pattern of new learning and an overall exciting goal.
Bullock explained that the biggest proof of the existence of dark matter lies in the fact that stars should move more slowly as they distance further from the galaxy. Instead, these stars move at the same speed at which stars closest to the galaxy move, leading to the conclusion that dark matter actually exists.
As of now, dwarf galaxies are the “potential beacon” to discovering the mystery of dark matter as Bullock explains. By finding dark matter, which annihilates into gamma rays, these rays can be detected by gamma ray telescopes.
These discoveries and the unsolved mysteries surrounding the discoveries were a significant part of the show.
Overall, Bullock had fun working with National Geographic.
”I felt the people doing the show were knowledgeable,” Bullock said. “National Geographic knew what they were doing, it was a positive experience and I knew they weren’t going to misrepresent anything I said.”