Professor of Science Writing at MIT and award winning author, Marcia Bartusiak discussed the birth of modern cosmology that came with Edwin Hubble's announcement in 1925 that our universe was far larger than previously believed, and filled with other galaxies. Continued research by Hubble forced Einstein to reevaluate his own cosmic model and accept the idea that the universe was expanding.
Yet, Hubble's conclusions were built on the work of lesser known astronomers, she pointed out. For instance, in 1912, Henrietta Leavitt discovered a kind of "cosmic measuring tape," by connecting blinking stars to their luminosity and distance. Another astronomer, Vesto Slipher, actually was the first to discover the movement or expansion of galaxies, she noted.
By imagining the reverse of galaxies' expansion, we can get an idea of the Big Bang, the tiny "primeval atom" (proposed by Georges Lemaitre) from which the universe emerged. The universe expanded into a kind of "Swiss cheese" pattern, with galaxies clustered together in web-like structures, separated by empty space, she detailed. Our entire universe could actually be a slower-paced part of a faster, expanding universe, she said. Bartusiak noted that we are living in a golden age for astronomy, with a number of telescopes that can capture data beyond the visible spectrum, including radio, X-ray, infrared, and ultraviolet.
Apollo Moon Mission
First hour guest, author Craig Nelson talked about the Apollo 11 moon landing & mission. Among the interesting facts he shared:
* Pigs were first used as test subjects in space, before being replaced by monkeys.
* Neil Armstrong was almost killed three times during NASA test missions.
* From the Moon, the Earth appears like "a blue sun"-- it's 8 times brighter than the Moon appears to us on Earth.