Student Voice


February 26, 2024



Astronomy professor hosts popular series of talks and viewings

November 18, 2015

A series of lectures put on by the physics department is attracting more than just physics and astronomy students.

Professor Eileen Korenic spoke for half an hour about the gravitational constant, in one of a series of talks that she has given throughout the semester Tuesday night at 8 p.m. in the Centennial Science Hall

Korenic said that the talks that she gives, about various astronomical concepts, have a long history.

“I started doing them about 12 years ago, just because I came across some really interesting things, like in astronomy magazines, and I thought, ‘there isn’t really a way to work that into a classroom,’” she explains.  “I thought it would be really nice to have another mechanism for getting information to students, and out to the public.”

On Tuesday night, the lecture hall was brimming with students, squeezing into the available seats, and the occasional member of the community. Korenic discussed the evolution of attendance to her presentations.

“When we first started, we used to have an attendance of maybe four people who would come,” she said. “And then I started offering extra credit to the astronomy classes and the numbers went up to about 20.”

“I think once you establish something as being a regular program, then people know that it exists, and they start telling their friends, ‘let’s go do that,’” Korenic said. “They find out it’s not as complicated or as math­-oriented, maybe, as they were scared it might be, and so it’s just been building these past few years.”

Tuesday night’s session was titled, “The Gravitational Constant is Constant. Duh!” The theme, the gravitational constant, sounds dauntingly scientific until Korenic embarked on a brief explanation. “Tonight we’re talking about the gravitational constant, ­we use the word constant when we want to say that there’s a proportionality between something,” she said. “Isaac Newton said there’s a proportionality between the force of gravity and how much mass objects have, that there’s a proportionality between the force of gravity and the distance­-squared between those objects.”

Korenic discussed how the gravitational constant was proposed and eventually measured. “Whenever you have some sort of proportional relationship, you can either just say they’re proportional and leave it at that, or you can say, ‘set them equal to each other, and if you put the correct constant in, then that mathematically shows the proportionality,’” she said.

“Finally someone said, ‘wait a minute, we can use that experiment to actually get a value for that number! Let’s do that.’ And so, the question is that number fixed for all time, that’s a number that defines our universe? It could also just be a number that changes as space ­time changes.”

Korenic said that the gravitational constant does appear to be just that, constant, in most cases.  “There seems to be some evidence that, for right now, that number does seem to be constant for all normal intents and purposes. But start going to the very small, getting into the quantum world, it may be that that constant just disappears, it just doesn’t even need to exist anymore.”

According to Korenic, that might not be the only exception to the rule. “The other place where we would see things that are very small would be at the very beginning of the universe, where we think the big bang started from a dimensionless point, and so there wouldn’t have been any gravity then either, until the universe started to expand. And when it reached a certain size, now gravity became the first force to differentiate itself.”

“So the question is, is it really constant?” she said. “Are the proportionalities the same for all time, and in all places? And it seems to be yes, so far as we can measure right now, but we’ve only been measuring for a couple hundred years.”

When Korenic explained it, the concept doesn’t sound that complicated. This is apparent when one realizes that astronomy and physics students are not the only ones showing up to these talks. Community members also find their way into the crowded lecture hall.

“We’re starting to get more and more people from the community,” Korenic said. “Now when I do a count, because I do give extra credit, I can tell how many people who are there are students, there [are] about 150 people present and about 30 of them were from the community.”

Korenic gave her interpretation of the response from her audience. “I can see the response on their faces, that they seem to be really engaged with it, and I don’t see too many people looking puzzled, like ‘this is way over my head’ and I watch for that, because that’s giving me a clue about how mathematical, or not mathematical, to make the talk, or what kinds of jargon can I use.”

“I think one of the things that always strikes me as funny is, if I use a word, that at first I think nobody’s going to know what it means. So I use the word, and I try and define it, and I will always see some people look like, ‘Oh, of course I know what that is.’ So I think the audiences that come are really pretty well-­informed about astronomy.”

One student agreed with this assessment. Kendell Hayes attended the talk on Tuesday for the extra credit she received for going. “I thought it was cool,” she said. “I mean, we learned that stuff in astronomy, so, I understood it more.”

“If you’re interested in that stuff, it’s fun to interact with people who are also interested,” she said. She said that she would advise other students to go to the talks. “I’d say, try it out. See what you think.”

There are many opportunities to attend more astronomy talks in the future. The dates of future talks, Korenic remarks, are “all listed on the physics webpage.”

She also said that Glenn Spiczak, astronomy professor, has a list called the Stargazers. “He will email when there’s going to be a talk, or some other kind of astronomical event. You know, we had that lunar eclipse there were some students who got together, they just wanted to watch it from the deck. If you were called in, or if you were on that email list, you might have wanted to come to that. So, he sends out notices about other events. His email is, and ask to get added to the Stargazers list and then you will get notified.”

Korenic added that she enjoys her astronomy talks.“I really like giving them, I think it’s really fun to do,” she said. “When I was a student in college, and even before that, the university that was in my town was University of Wisconsin-Milwaukee, and there was a professor there who used to give talks. He would do much more extended, very big demonstrations and I thought, ‘someday I would like to do that.’”

“I would like to be the person who maybe inspires somebody else to think about science,” she continued. “You can work on a little corner of research, and that’s important too, but, it’s like, I would so much rather help people to be more scientifically literate, and deal with the science in the world.”

Korenic said that she is open to input on the subject of her talks.

“If they have ideas for talks that they would like to hear about, I’m always happy to accept emails. Otherwise, I choose things that I’m interested in.” she said.