from the world's big
Found in Antarctica: A 'weirdo particle' that predates the sun
A tiny grain found within a meteorite in Antarctica sheds light on how the solar system itself came to be.
- Researchers cut open a small meteorite found in the LaPaz icefield in Antarctica to uncover a very surprising find.
- Inside this meteorite was a small inclusion that they determined came directly from the nova of a white dwarf to Earth.
- By studying the inclusion's composition, researchers were able to glean new insights into the thermodynamics of white dwarf novae, ultimately shedding light onto how solar systems like ours formed.
In a meteorite NASA retrieved from the LaPaz icefield in Antarctica, researchers have uncovered a grain of stardust that formed before even our own sun had come into existence. What's more, this grain of material sheds insight into how solar systems like our own form.
"Sometimes research is about satisfying your curiosity. One of the greatest curiosities is how the universe was formed and how life started," said Jane Howe, one of the researchers on this project. "And this weirdo particle showed us something we didn't know before."
How a white dwarf made 'this weirdo particle'
In a sense, everything is composed of the same stardust that was found in this meteorite in Antarctica — all matter comes from either the Big Bang or stars, in one way or another. But it's rare to find matter that originated directly from the source. Specifically, the grain from the LaPaz meteorite, called LAP-149, is believed to have come directly from a white dwarf nova.
There's no fusion going on in a white dwarf, so they typically aren't making new stuff in the universe. White dwarfs are the remnants of a certain old stars that have burned through their fuel, and their cold, white glow is just the leftover energy from the old star's fusion reactions. When a white dwarf orbits another star in a binary system, however, that white dwarf can suck up material from its larger companion star. Once a white dwarf accumulates enough material from its companion star, the matter can periodically reach temperatures high enough to trigger fusion again in a violent explosion.
Most of us are familiar with supernova; this is a similar event, though less violent. When a white dwarf goes nova, it shoots out clouds of stardust composed of different elements that can eventually condense and find their way to Earth. This is what happened with LAP-149, which found its way to Antarctica.
The secrets gleaned from LAP-149's composition
Scanning transmission electron microscopy data of LAP-149 under various imaging modes. Figure d shows a LAP-149's composition in false colors: carbon, red; oxygen, blue; and silicon, green.
Haenecour et al., 2019
How did the researchers know that LAP-149 truly came from outside the solar system? When analyzing the material, they found that the grain was highly enriched in the carbon isotope 13C, far beyond what one would expect for anything that was formed within the solar system. "The carbon isotopic compositions in anything we have ever sampled that came from any planet or body in our solar system varies typically by a factor on the order of 50," said lead author Pierre Haenecour in a University of Arizona press release. "The 13C we found in LAP-149 is enriched more than 50,000-fold. These results provide further laboratory evidence that both carbon- and oxygen-rich grains from novae contributed to the building blocks of our solar system."
Because LAP-149 was extrasolar in origin, the researchers could study its composition and gain insights into the processes from its source, a white dwarf nova. Using ion and electron microscopy, the research team found a small inclusion, just a few hundred nanometers in size, consisting of oxygen-rich silicates within the larger graphite structure. This turned out to be a very exciting find — there have been no other grains of stardust found that match this composition.
The material in a nova depends on the composition and density of the white dwarf star that produced it, and traditional models of the thermodynamics of such novae did not correspond with what was found in LAP-149. Because oxygen-rich silicates were found within LAP-149's graphite, this work enables scientists to further refine their understanding of the thermodynamic processes that go on in novae, specifically how grains of stardust form and move. It also shows that carbonaceous and silicate dust can be produced in the same ejection from a nova, ultimately providing insight into how solar systems such as ours were formed.
Taking a broader view, however, this work serves as an incredible example of how far science has come. Not only could we identify that a meteorite was formed from the clouds of stardust surrounding a white dwarf star undergoing a violent, explosive, and creative process billions of years ago, we were able to study its composition and learn something about how that process unfolded. Through research such as Howe, Haenecour, and colleagues', we'll be able to learn even more about the cosmos in the future.
- Solar nebulae revealed as sources of earth's water - Big Think ›
- Jupiter formation: Scientists discover new origin story - Big Think ›
Educators and administrators must build new supports for faculty and student success in a world where the classroom might become virtual in the blink of an eye.
- If you or someone you know is attending school remotely, you are more than likely learning through emergency remote instruction, which is not the same as online learning, write Rich DeMillo and Steve Harmon.
- Education institutions must properly define and understand the difference between a course that is designed from inception to be taught in an online format and a course that has been rapidly converted to be offered to remote students.
- In a future involving more online instruction than any of us ever imagined, it will be crucial to meticulously design factors like learner navigation, interactive recordings, feedback loops, exams and office hours in order to maximize learning potential within the virtual environment.
An MIT astronomer famously explained why aliens haven't contacted us yet.
A study finds people are more influenced by what the other party says than their own. What gives?
- A new study has found evidence suggesting that conservative climate skepticism is driven by reactions to liberal support for science.
- This was determined both by comparing polling data to records of cues given by leaders, and through a survey.
- The findings could lead to new methods of influencing public opinion.
Mind the cues<div class="rm-shortcode" data-media_id="CabkeAzx" data-player_id="FvQKszTI" data-rm-shortcode-id="169377c88f392a86f6c42180b74820a5"> <div id="botr_CabkeAzx_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/CabkeAzx-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/CabkeAzx-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/CabkeAzx-FvQKszTI.js"></script> </div> <p>The gulf in accepting the science behind climate change also exists among party elites. It is well known to any American who is attentive to the news, as party leaders are often more than willing to discuss their take to journalists.</p><p>Using polling data going back to the 1980s, the researchers were able to create a chart showing the aggregate amount of climate skepticism among the general population. A similar diagram showing the Republicans' skepticism dating back to 2001 was sourced from a previous, similar study. It was shown to be highly correlated with the one produced for this study.</p><p>These charts were compared with media content from prominent newspapers that included implicit or explicit stances on climate change by significant political figures. These thousands of articles were classified by using key terms and which major political figures were quoted or referenced. The researchers compared the number of cues over time to measured skepticism and looked for "<a href="https://en.wikipedia.org/wiki/Granger_causality" target="_blank">Granger causality</a>," the tendency for one variable to predict the future value of another variable.</p><p>The model shows evidence of both in and out-group cue effects, though the repulsion to out-group cues was much more evident. A significant increase in Democratic cues in favor of climate science was followed by a rise in skepticism among Republican voters. Importantly, the cues lead, rather than follow opinion, and do so with consistency. Changes in view did not predict changes in the number or direction of cues. </p><p>The researchers also surveyed nearly 3000 adults to demonstrate the concept. This involved showing them a statement on the scientific consensus around climate change and a cue from either a Republican or a Democrat. This test confirmed the previous observation and provided further support for the notion that signals from leaders cause an increase in skepticism among some respondents.</p><p>Before my left-leaning and Democratic readers get too smug, this research references previous studies demonstrating a similar effect in the lead up to the Iraq War. However, in that case, the Democratic Party elites' mixed messages were countered by a Republican Party united behind the idea of invasion. The effect on the Democratic party rank and file was similar to that observed in this case. </p><p>Several other studies have examined effects similar to this for other issues. This study's importance is its focus on out-group cues and the effort placed into demonstrating a causal relationship between the statements of certain party elites and public opinion. Most previous studies focused purely on in-group cues or failed to differentiate between the two. </p>
Can thinking about the past really help us create a better present and future?
- There are two types of counterfactual thinking: upward and downward.
- Both upward and downward counterfactual thinking can be positive impacts on your current outlook - however, upward counterfactual thinking has been linked with depression.
- While counterfactual thinking is a very normal and natural process, experts suggest the best course is to focus on the present and future and allow counterfactual thinking to act as a motivator when possible.
“Upward” versus “downward” counterfactual thinking<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzQ1NDYxOS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NDM2MDY2OX0.njWs1qrV1vDBxU1V75tUduUW4TjJvEHglDWsK8ZF2l4/img.jpg?width=1245&coordinates=0%2C556%2C0%2C209&height=700" id="a15fa" class="rm-shortcode" data-rm-shortcode-id="98314d4d2b256ed08f42d369fe4ae080" data-rm-shortcode-name="rebelmouse-image" alt="concept of man thinking about the past one line drawing counterfactual thinking" />
What are upward and downward counterfactual thinking?
Image by one line man on Shutterstock<p><strong>What is upward counterfactual thinking?</strong></p><p>Upward counterfactual thinking happens when we look at a scenario and ask ourselves "what if" in terms of how our life could have turned out better. </p><p>Examples of upward counterfactual thinking are: </p><ul><li><em>"I wish I had taken that other job instead of this one 10 years ago - my life would be so much better if I had." </em></li><li><em>"I wish I would have gotten the part in that high school play, maybe I could have gotten into a theatre school and became an actor…"</em> </li></ul><p>Both of these examples have the ideology that if you had made different choices, your life right now would be improved. </p><p><strong>What is downward counterfactual thinking?</strong></p><p>Downward counterfactual thinking is, naturally, the opposite of upward counterfactual thinking in that we think about how things could have been worse if other decisions had been made. </p><p>Examples of downward counterfactual thinking are: </p><ul><li><em>"I'm so thankful I studied secondary education in university instead of psychology like I had originally planned - I love teaching high school kids and I never would have gotten to do that…" </em></li><li><em>"I'm so happy I left David when I got the chance, I can't imagine still being in an unhappy marriage with someone who doesn't support me…"</em> </li></ul><p>In these examples, we see the idea that if you had made different choices your life would not be as good as it is right now. </p>
How counterfactual thinking can impact your life<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzQ1NDYxNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNjI2MDQxOX0.DIVQ-Yk0d6yE3tc743MH1Fz2pOg1TGHLmhp8dPp9UdY/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="522d7" class="rm-shortcode" data-rm-shortcode-id="da7df6ad916b043e3610223900d0f8df" data-rm-shortcode-name="rebelmouse-image" alt="man thinking what if written on chalkboard" />
How do upward and downward counterfactual thinking impact your life?
Photo by Brasil Creativo on Shutterstock<p>While many people don't see the point in "what if" scenarios, various studies have found that downward counterfactual thinking can be more associated with psychological health compared with upward counterfactual thinking. Not only that, but research has also shown upward counterfactual thinking can be linked with current and future depression.</p> <p><strong>Downward counterfactual thinking tends to be more associated with psychological health </strong></p><p>According to a <a href="http://journal.sjdm.org/jdm06136.pdf" target="_blank">2000 study</a>, downward counterfactual thinking can be linked with better psychological health compared to upward counterfactual thinking. More importantly, in cases where downward counterfactual thinking did lead to negative feelings, those feelings acted as something of a motivator for people to take productive actions to better their current situation. </p> <p><strong>Upward counterfactual thinking tends to be more associated with depression </strong></p><p><a href="https://www.sciencedirect.com/science/article/abs/pii/S0272735816301714#:~:text=An%20upward%20counterfactual%20(as%20opposed,Markman%20and%20McMullen%2C%202003)." target="_blank">According to a 2017 study</a> that pooled a sample of over 13,000 respondents, thoughts about "better outcomes" and regret (upward counterfactual thinking) were associated with current and future depression. </p> <p><strong>Downward counterfactual thinking can actually improve your relationships and is more often engaged in by women than men.</strong></p><p>In a <a href="https://dspace.sunyconnect.suny.edu/bitstream/handle/1951/67589/Studer_Thesis.pdf?sequence=1&isAllowed=y" target="_blank">2016 research paper submitted</a> to the Department of Psychology at the State University of New York at New Paltz, downward counterfactual thinking in regards to romantic relationships was associated with relatively positive relationship outcomes. Interestingly, women were more likely than men to engage in downward counterfactual thinking about their romantic life. </p> <p><strong>Upward counterfactual thinking can have some benefits in certain scenarios. </strong></p><p>When we look back after a failed test and think "I wish I would have studied more" - this motivates us to study harder the next time a test comes up. In this way, upward counterfactual thinking (or the negative version of "what if") can actually benefit us. </p> <p><strong>This can be difficult, though, because much of the time upward counterfactual thinking is more associated with a pessimistic outlook that can be unmotivating. </strong></p> <p>Thinking in the past tense can be motivational (and even healthy) at times, but the best thing to do is look forward. </p><p>While counterfactual thinking as a whole can be used to motivate us to make better choices or appreciate where we are in life, <a href="https://www.psychologytoday.com/us/blog/darwins-subterranean-world/201809/the-psychology-what-if" target="_blank">this Psychology Today</a> article suggests that we should come up with ways to move on and focus on the present and the future instead of the past. Using counterfactual thinking as a motivational tool can be very helpful if we don't get stuck in the "what if" mindset that tends to pull us out of the present and back into the past, where things will always remain the same. </p>