[ad_1]
Vera Rubin did not “discover” dark matter, but put it on the map.
Dark matter is a wild concept. It’s the idea that a mind-boggling percentage of all matter in the universe can be invisible, and totally different from the matter that makes up the Earth. Rubin is celebrated because she forced much of the astronomical community to take her seriously.
That moment of judgment came in 1985, when she stood before the International Astronomical Union and presented to the public some of the data she had collected.
His data showed that stars at the edges of multiple galaxies moved in ways that made no sense, according to the rules of physics. One possible explanation for this strange phenomenon, Rubin suggested, was the existence of a mysterious “dark matter” at the edges of the galaxy. In the decades since this speech, dark matter research has exploded, revolutionizing astronomy.
In Bright galaxies, dark matter and beyond, a new biography of Rubin, science journalist Ashley Yeager explains how Rubin, who died in 2016, went from a young researcher whose bold ideas were initially ignored to the kind of scientist who could change an entire field. In 2020, we interviewed Yeager for an episode of the Inexplicable podcast on dark matter. A transcript of our conversation, slightly edited for length and clarity, follows.
Noam Hassenfeld
When did Vera Rubin first become interested in astronomy? What is its origin story?
Ashley yeager
Around the age of 11, she started looking at the stars. Vera and her sister, Ruth, shared a room in their Washington, DC townhouse. And Ruth remembers Vera was constantly crawling over her at night so that she could open the windows and look at the night sky and start following the stars. So it’s clear that Vera was captivated by the night sky. And it marked her.
She then went to Vassar, where she studied astronomy. [While at Vassar, she met a mathematician named Robert Rubin.] They ended up getting married. And it led to one of the biggest decisions in Vera’s life, as she wanted to go to the graduate school of astronomy.
She had entered Harvard, but Robert Rubin was at Cornell. He was well advanced in his graduate studies. They had to make a choice and Vera said, “Let’s stay together. I will come to Cornell with you and do my masters in astronomy while you finish your doctorate in physics.
Noam Hassenfeld
Isn’t that a wild choice? Choosing Cornell on the Basis of a Husband?
Ashley yeager
It’s the late 1940s. And Vera, in some ways, was very traditional, although she wasn’t traditional in other ways. She felt that she was expected to marry at the end of her four years in Vassar. It was always something that was expected by society.
And I actually think it made her more successful than she might have been, if she’d been to Harvard or Princeton or whatever, just because of the exposure that she was. had. There was an intellectual freedom she had at Cornell, to be able to delve into various questions in astronomy that she probably would have been left out if she had taken a more structured graduate program.
Noam Hassenfeld
So she’s at Cornell. She probes the questions. She has great intellectual freedom. What are the big questions that occupy his mind?
Ashley yeager
Most important, which becomes his master’s thesis, is really the idea of ”Is the universe spinning?” “
Noam Hassenfeld
Wait, Is it that the universe turns?
Ashley yeager
So, probably not. It was a question asked by a very eccentric astronomer named George Gamow. Vera’s husband actually showed Vera this paper that George Gamow wrote about this idea. And she thought, “Well, why don’t we try to answer that question?” “
Noam Hassenfeld
The kind of question that, if she had been to another college, she might not have had the freedom to dive in?
Ashley yeager
I think so. I have the impression, reading the literature and going through history, that it probably would have been guided to a more traditional question.
And as she began to skim through the data, the numbers started to suggest that there was this weird lateral movement that could perhaps be interpreted as universal rotation. She presented her idea to her master’s thesis supervisor, William Shaw.
He said, “Your conclusion is really good. I want to present it under my name at this next astronomy conference.
And Vera says, “No! I may not be a member of this society yet. But you don’t show me my data. I will present it under my own name, through thick and thin.
Noam Hassenfeld
So she ?
Ashley yeager
Yes. She goes to this meeting. Apparently the drive from New York to Pennsylvania, where the meeting was being held, was heartbreaking. It was winter, snowy. They had a newborn baby in the car. His father actually drove because he was the only one with a car at the time.
But she does the presentation, and the reaction is less than great. There are severe criticisms in the room. Lots of teasing. She has one person, Martin Schwarzschild, who encourages her. He says, “It’s really interesting. But we need more data to be able to draw this conclusion. “
And it’s a review that really sticks to her throughout her career. Later, she really tries to have or collect as much data as possible to support her conclusions, just because of this experience.
Noam Hassenfeld
What happens next?
Ashley yeager
She takes a little break, because she really has this strong feeling of wanting to start a home and start a family. There’s that moment in the early 1950s when she’s at the playground with her son. She had read astrophysical journals to keep in touch with what was going on in astronomy.
So her son is playing in the sandbox and she reads the newspaper, and she bursts into tears because she so misses doing research. She lacks that curiosity to ask questions and research data, and really try to find the answers to how the universe works.
That’s when her husband said, “You have to go back to school. It’s time. Child care will be found. We will find out how to prepare dinners. But let’s do it.
Noam Hassenfeld
She therefore returned to astronomy. And finally, she starts doing research at Kitt Peak National Observatory, doesn’t she? How is it ?
Ashley yeager
We’re talking about the end of the sixties. It’s an 84-inch telescope, very large. Vera is at the telescope with Kent Ford, her collaborator. They are looking at this galaxy called Andromeda, which is our closest neighbor. They’re looking at these very young, hot stars at the edge of the galaxy, and they’re trying to get the speeds of those stars – how fast are those stars spinning around Andromeda?
So they look at the data, and they’re like, ‘Oh my God, that’s not what we expected’. The assumption was that the closest stars would fly around the sun quickly, and the stars farther away would go very slowly. But these stars were moving faster than expected.
The only way for these distant stars in the galaxy to move that fast is [that] something must be going on there that we don’t understand.
Noam Hassenfeld
What does she think is going on?
Ashley yeager
Well, she’s not really sure. And again, she doesn’t like to guess or talk without data. So she and Kent Ford, and a few other people, really start doing a systematic study of galaxies.
It’s 20 galaxies, then 40, then 60. And they all show this weird star behavior, these stars far in the galaxy, moving way, way too fast. So at that point, you know, the astronomical community is like, “Okay, we’ve got to deal with this. “
In 1985, Vera Rubin gave this lecture at the IAU. She says: “Nature has played a trick on us. That we have studied a matter which constitutes only a small fraction of the universe. The rest of the universe is something we don’t understand, and we can’t see it.
And I think because she’s done this in so many galaxies – we’re talking 60 galaxies – there really was no way to deny it. It was really his work that pushed the community to its limits, to say that we have to accept the idea that dark matter exists.
Noam Hassenfeld
Seems like if you really want to turn our whole conception of the universe upside down, you’ve got to come up with data.
Ashley yeager
Yeah, absolutely. Because she clung to this critique of her masters and doctoral work – she would just go after the data and really make sure the story she was telling from that data rings true.
One of the things that made her a remarkable scientist was her persistence. She faced many roadblocks, not least because she was a woman scientist in the 1940s, 1950s, 1960s. She really had to persevere. Unfortunately, she will never be able to see or know what dark matter is. But I don’t know if she had a problem with it. She would be proud to have opened up a whole new field of astronomy and physics.
She basically created more questions than answers, and I think that’s the mark of a remarkable scientist: when you open up those questions that no one had ever thought of before. When you create a whole new generation of scientists who can answer it.
[ad_2]
Source link