LectureHop: When Bad Things Happen to Good Galaxies
Written by Bwog Staff
Bwog’s resident Star Gazer Zach Kagan writes in with tidbits of information from Hugh Crowl‘s lecture, “When Bad Things Happen to Good Galaxies,” on doom and gloom for major galaxies. Behold the cosmic drama!
The Audience at the most recent Public Lecture and Stargazing, held in the bowels of Pupin (correctly pronounced “pew-PEEN”) Hall, spanned ages 8 to 88. The turn out was surprisingly high for 8 pm on a Friday. Assembled were families with kids, high school students scribbling down answers on their worksheets, bored NYU students, and a hodgepodge of NYC space lovers. The lecture, given by a cheery Columbia post-doc, was entertaining and not too technical, and enlivened with beautiful images and nifty 3D animations.
The bad things Dr. Crowl refers to in the title of his lecture are galactic collisions that send stable, disc-shaped galaxies into utter chaos. M82, a galaxy tucked away in the Ursa Major constellation, is one of those unfortunate galaxies, influenced by its larger neighbor, M81. The shape of the galaxy has been deformed and gasses have been forced through M82’s core creating a large quantity of baby stars. But there’s a bigger problem—larger galaxies don’t just bully smaller ones into making more stars, they eat them, too. The gravitational force of the larger galaxy rips the smaller one apart and then absorbs its stars. The black holes that lie at the center of most galaxies collide and combine, making a bigger galaxy. It has happened to our closest neighbor, Andromeda, as well as our own Milky Way several times, and one day these two galaxies will duke it out. Of course this is on the time scale of hundreds of millions of years, so don’t worry too much about it.
The second half of the evening entailed a tour of Pupin’s telescope, and an explanation of its fascinating history. A grad student led us upstairs to the mysterious 15th floor of Pupin—essentially its roof. We climbed a set of stairs inside a large wooden dome where we learned about the observatory’s history. The dome was built in 1929 alongside the rest of Pupin, and much of the original wire and pulley system used for opening the slit in the dome is still use. The original telescope was a giant refracting telescope (much like the ones pirates used). It was commissioned for the Czar of Russia, but after his fall during the Russian Revolution, the telescope was left in storage before Columbia bought it and installed it on top of Pupin. A few years ago, Columbia sold the aging telescope to a museum and replaced it with a smaller, more modern model, which looks a bit lackluster given its size in comparison with the dome.
Unfortunately it was too cloudy to actually stargaze, but there was plenty more to do. Another grad student gave a demonstration using a 3D projector. The audience put on pairs of 3D glasses and watched as nebulas and colliding galaxies popped out at them. Dr. Crowl confessed to Bwog that the evening of educational fun had an ulterior motive. “We use it as a way to trick, well not trick… seduce, people into liking science.” Consider us debauched!
Beautiful space picture via Wikimedia
Tags: astronomy, baby stars, black holes, Boney M, galaxies eating galaxies, lecturehop, pupin uris and butler all have below the belt suggestions, science, size matters, take bwog out on a stargazing date please!