All stories start somewhere – even the incomprehensibly vast expanse above us has a beginning. Scientists have long studied the cosmos, searching for answers to the “how’s” and “why’s” of life, and that effort continues to this day.
From concepts such as ‘Cosmic Dawn’ and ‘redshift,’ UNLV astronomer and computer scientist Paul La Plante focuses on topics that improve our understanding of where it all began.
“Cosmology is about studying the universe at the oldest and biggest scales that we can fathom,” he said. “We’re trying to paint as complete a picture of this early part of the universe’s history as we can, and trying to understand how it all fits together is a big part of what I research.”
His observations are done the old-fashioned way with telescopes, but with a modern twist involving supercomputers. Two of the most important sites where La Plante and colleagues perform cosmological data collection are the radio telescope in South Africa and the microwave telescope at Chile’s .
“A lot of telescopes get to see the universe through pure observation, similar to how our eyes work,” La Plante said. “But others are able to ‘hear’ the universe, in some sense. We call them radio telescopes, and we’re hearing in the same frequency spectrum that FM radio broadcasts. So, when you tune your radio to a certain frequency, if it were powerful enough, you’d be able to pick up the very distant universe.”
And because of their incredibly sensitive instruments, these observatories are purposely built far away from people to dodge different types of pollutants. For the radio telescope in South Africa, the FM radio signal is a large source of potential pollution. For similar reasons, Chile’s microwave telescope is located in the mountains to get above as much of the air as possible, improving measurements.
“The data we collect allows us to do simulations of the universe at both the very largest and smallest scales, like stars, and where they meet together in galaxy formations,” La Plante said. “We just now are building some instruments capable of observing them for the first time. And we’re trying to unpack a lot of information about these dots in the sky with limited data.”
Our picture of the universe is always changing, including from remote observations such as from the recently-launched (JWST). In about a year since its launch, JWST has rescaled our proportions of the known universe.
“It’s shown us that some galaxies that we’re detecting are bigger than we originally thought,” he said. “That means our understanding is being rewritten, as there’s so much more room for additional planets and possibilities. Does this mean we have to update our measurement processes and models in order to explain this new James Webb data? It’s an ongoing conversation happening in the field of astronomy.”
I sat with La Plante to help break down asteroid-sized science into more manageable meteorites of information. Read on for some of his insights into the lesser-known facts about space, in general, and the generational advancements made in the field of astronomy.
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Back to the Future
I like to sometimes think of telescopes as time machines. And the reason for that is you don’t actually see a star or galaxy as it is right now. You see it as it was when it emitted the light we’re detecting now.
For example, the sun is about eight light minutes away from us, meaning it takes the light from the sun about eight minutes to reach us here on Earth. So, if for some reason the sun suddenly went out, it would take us eight minutes to find out about it.
That same principle applies to stars in our Milky Way and other distant galaxies. The light from these very early galaxies has been traveling for 12 or 13 billion years to get to us on Earth. We see those galaxies as they were back then, not as they are right now. It’s old news – the oldest news in the universe, and that’s that we’re trying to measure.
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The Universe is Closer than You Think
Cosmic Microwave Background Radiation is known as the universe’s baby picture. This light is the oldest that we can observe, giving us our clearest understanding of the universe’s origin. And by interpreting that signal, we can learn more about it.
ҳ| 鶹ýӳ 1% of the scrambled static that you see on an old-school antenna TV is leftover radiation from the early universe or big bang.
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The Big Bang Theory (Minus Sheldon)
We have this period in our history where time, as we know it, started. In that instant, nearly 14 billion years ago, is the beginning of our understanding of where things started. And we have a coherent cosmological model for its process of evolving after that. But as far as what was before that? I don’t know. It’s an unanswered question for now.
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Only Getting Bigger
The universe is expanding, and what I mean by that is the space in between galaxies is getting larger. So, even the part of the observable universe that we’re aware of from the big bang, that space between galaxies has gotten larger since the start of time.
I’m hoping that within 10 years, we’ll have a new way of detecting these galaxies that will tell us a lot about this part of the universe’s history. We’re going to build even better instruments that are more precise that will give us a more complete picture of the universe.
La Plante is an active member of the , bringing together anyone who studies astronomy in the state. He currently has active research grants for his work involving telescope data and using it to create more accurate pictures of the universe related to the future NASA missions: and .
UNLV currently offers a program for middle school students interested in studying the stars through , a weeklong astronomy camp. For those looking to take the first steps toward a career in cosmological data science, look no further than the .
