Something strange is going on with the North Star
It keeps breaking astronomer's models of how stars are supposed to act.
Something's up with the North Star.
People have watched the North Star for centuries. The bright star, also known as Polaris, is almost directly above Earth's North Pole and serves as a landmark in the sky for travelers without a compass. It's also Earth's closest cepheid, a type of star that pulses regularly in diameter and brightness. And Polaris is part of a binary system; it's got a dimmer sister, known as Polaris B, that we can watch circling it from Earth.
"However, as we learn more, it is becoming clear that we understand less" about Polaris, wrote the authors of a new paper on the famous star.
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The problem with Polaris is that no one can agree on how big or distant it is.
Astrophysicists have a few ways to calculate the mass, age and distance of a star like Polaris. One method is a stellar evolution model, said new study co-author Hilding R. Neilson, an astrophysicist at the University of Toronto. Researchers can study the brightness, color and rate of pulsation of the star and use that data to figure out how big and bright it is and what stage of life it's in. Once those details are worked out, Neilson told Live Science, it's not hard to figure out how far away the star is; it's fairly simple math once you know how bright the star really is and how dim it looks from Earth.
These models are especially precise for cepheids, because their rate of pulsing is directly related to their luminosity, or brightness. That makes it easy to calculate the distance to any of these stars. Astronomers are so sure they understand that relationship that cepheids have become critical tools for measuring distances all across the universe.
But there are other ways to study Polaris, and those methods don't agree with the stellar evolution models.
"Polaris is what we call an astrometric binary," Neilson said, "which means you can actually see its companion going around it, sort of like a circle being drawn around Polaris. And that takes about 26 years."
Researchers haven't yet made detailed observations of a full circuit by Polaris B. But they've seen enough of the companion star in recent years to have a pretty detailed picture of what the orbit looks like. With that information, you can apply Newton's laws of gravity to measure the masses of the two stars, Neilson said. That information, combined with new Hubble Space Telescope "parallax" measurements — another way to calculate the distance to the star — lead to very precise numbers on Polaris's mass and distance. Those measurements say it's about 3.45 times the mass of the sun, give or take 0.75 solar masses.
That's way less than the mass you get from stellar evolution models, which suggest a value of about seven times the mass of the sun.
This star system is weird in other ways. Calculations of the age of Polaris B suggest that the star is much older than its bigger sibling, which is unusual for a binary system. Typically, the two stars are about the same age.
Neilson, together with Haley Blinn, an undergraduate student and researcher at the University of Toronto, generated a huge set of models of Polaris to see whether those models could reconcile all the data known about the system. They couldn't.
One possibility is that at least one of the measurements here is just wrong, the researchers wrote. Polaris is an especially difficult star to study, Neilson said. Located above Earth's North Pole, it's outside the field of view of most telescopes. And the telescopes that have the necessary equipment for precisely measuring the star's properties are usually designed to study much fainter, more distant stars. Polaris is too bright for those instruments; in fact, it's blinding for them.
But the data researchers do have seem trustworthy, and there's no obvious reason to doubt that information, Neilson said.
Those findings led Neilson and Blinn to another, stranger explanation: Perhaps the main star of the Polaris system was once two stars and they slammed together several million years ago. Such a binary collision, Neilson said, can rejuvenate stars, pulling in extra material and making the stars look like they just "went through the fountain of youth."
Stars that result from binary collisions don't neatly fit stellar evolution models, and such an event could explain the discrepancy found with Polaris.
"This would be an unlikely scenario, but not impossible," the researchers wrote.
So far, none of the solutions is wholly satisfying.
"It is challenging to draw significant conclusions beyond the fact that Polaris continues to be an enduring mystery, and the more we measure the less we seem to understand," Neilson and Blinn wrote.
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Originally published on Live Science.
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By Sascha Pare
Why should it be weird, rather than expected, that a star or solar system or galaxy out there somewhere doesn't conform to the fictional expectations of evolutionary theory?
"The fool hath said in his heart, There is no God" (Psalms 14:1; 53;1).
Soon or later these theories that seek to explain the universe from an atheistic or skeptic perspective will fail, even as theories about evolution on our planet have been falsified for decades.
Man did not create the earth and heavens, but man did create all the gods that have come and gone. You shouldn't toss around words like fool and falsified, given your stance, as it's just too ironic...
"Know ye that the LORD he is God: it is he that hath made us, and not we ourselves; we are his people, and the sheep of his pasture" (Psalms 100:3).
Darwinian evolution requires long periods of time. Yet the contact points between layers of the geologic column tend to be flat. Around the Grand Canyon are two layers that are supposed to differ in age by 12 million years, and another two layers that are supposed to differ by over 100 million years. During those lengths of time significant erosional features should have formed and then been buried within the geologic column, especially since evolutionists propose that intervening missing layers entirely eroded away. Yet such erosional features aren't there, and the contact points are instead quite flat.
This observable evidence points to rapid deposition. The layers were laid down so rapidly, there wasn't time for erosion to occur between layers. And since these layers were deposited by some sort of water action, we need to have a catastrophic flood rapidly depositing the layers over large sections of the globe.
If you don't think this evidence affirms the existence of the God of the Bible, I would be most interested in hearing why it wouldn't. I can't think of any sort of scenario that could result in little or no erosion between layers of the geologic column, and rapid deposition of those layers over large areas of the globe through water action, within an atheistic or skeptic model of origins and history. But maybe you can think of an alternative, and if you can, I'd like to hear about it.
Pickle, please stop quoting scripture, it does little to help your argument. That Yahweh/El would become capital G God was a matter of religious interpretation and reflects the human compulsion for asceticism. All the gods worshiped in the Levant did not suddenly cease being useful devices once ascetic followers of Yahweh/El rejected the pantheon (to say nothing of the myriad gods worshiped by myriad peoples around the globe).
A discussion about post-glacial-retreat flooding could be a better place for your theories on, presumably, strata deposition and its correlation with the Great Flood. Such stories are endemic to traditional societies around the globe because the end of the last glacial period saw huge changes come to coastal and riverine environments - areas people have forever chosen to settle and call home. The Eridu Genesis - from which a huge amount of biblical Genesis was cribbed - ascribes the flood to gods upset that humans weren't worshipfully sacrificing enough. This is socio-religious equivocation - floodwaters ruined our homes and foodstuffs because we sinned too frequently and thus deserved divine punishment.
Specifically, your reference to the Colorado River Valley deposition layers has more to do with the catastrophic floods that resulted from glacial lake Missoula (and prior lakes from prior glacial retreats) bursting through earthen dams, draining colossal built-up reservoirs, and wreaking watery havoc on what we today call the western US.
I hope you enjoy the rest of your day. Be well.
But please note that it appears that your religious biases are hindering you from understanding or answering my question. I fail to see how your comments explain the stark lack of significant erosional features seen between layers evolutionists date to be as old as 500 million years (https://creation.com/flat-gaps). Certainly the draining of lake Missoula wouldn't leave behind a lack of significant erosional features. And Eridu Genesis doesn't help your case, since it doesn't explain how the lack of significant erosional features can exist within an atheist or skeptic paradigm.
Surely attacking someone else's religious beliefs is easier than proving one's own, especially when geologic phenomena is one's bible, and those phenomena don't support one's views. But give it a try anyway.