from the world's big
What can old stars teach us about the birth of our galaxy?
These needles in the vast galactic haystack take more effort to find, but they help piece together our origins.
Anna Frebel, Ph.D., is a member of the MIT physics faculty and earned her doctorate in astronomy from the Australian National University’s Mt. Stroll Observatory. She has received numerous awards for her pioneering work into the chemical and physical conditions of the early universe. They include the Ludwig-Biermann young astronomer award of the German Astronomical Society, the Annie Jump Cannon Award of the American Astronomical Society, and an NSF CAREER Award to continue her discovery of the oldest stars. Her book is Searching for the Oldest Stars: Ancient Relics from the Early Universe.
Professor Frebel’s research interests cover the early universe, and how old, metal-deficient stars can be used to obtain constraints on the first stars and initial mass function, supernova yields and stellar nucleosynthesis. She is best known for her discoveries and subsequent spectroscopic analyses of the most metal-poor stars and how these stars can be employed to uncover information about the early Universe. By now, she has expanded her work to include observations of faint stars in the least luminous dwarf galaxies to obtain a more comprehensive view of how the Milky Way with its extended stellar halo formed.
She carries out her observational research on old stars using the 6.5m Magellan telescopes in Chile through high-resolution optical spectroscopy. Recently, Professor Frebel also started a large supercomputing project to simulate the formation and evolution of large galaxies like the Milky Way in a cosmological context. The N-body dark matter halos will ultimately help her trace the cosmological path of the oldest stars from their birth in the early universe until their arrival in the Milky Way halo through various merger events. This huge data set will also enable to quantify the breadth of galaxy formation and the abundance of substructure of large galaxies, among many other things.
ANNA FREBEL: It has always been really important for us humans to understand what our past is. On Earth we do for example genealogy. We ask our parents about our grandparents and so forth to learn about the history. And astronomers do the same thing about the universe. So we are asking the question how did everything begin? How did everything start to evolve? How did everything fall into place so that Earth could form at some point together with our Sun and later as humans we could start to emerge. And so the work that stellar archaeologists are doing is to try asking and answering the question how did the chemical evolution of the universe begin? Which means how did all the chemical elements, how did they form and how were they produced? And we know that they are produced in stars and supernova explosions. All the elements of the periodic table are created in stars and supernova explosions. And we specifically have means with these old stars to reconstruct how each of these atoms, for example, iron atoms or carbon atoms or calcium, how this was all created for the first time in the very first stars about 13.5 billion years ago.
But how do astronomers actually know how old stars are? Well it's actually not that easy because we can't just go – first of all we can't go there and measure an age. And actually age dating in general with various astronomical techniques is very, very complicated. But we can use a different fact to our advantage. As I've said the elements are created in stars and supernova explosions, and there were actually no heavy elements heavier than hydrogen, helium, and lithium present at the very earliest times soon after the Big Bang. But with time and with time I mean over the billions of years since then all the elements were created successively in stars. And so their content has built up over time. Today the universe contains a whole two percent of all these heavy elements that we know in the periodic table, so everything except hydrogen and helium. And we use those facts because we just look backwards and we search for the stars that have the smallest amounts of all of these heavy elements. So we look for example for the most iron-poor stars. We like to use iron as our reference element.
And that takes us back to this very early time when there simply wasn't that much iron in the universe. So in order to determine that a star is old and hence interesting we need to do a chemical composition. We need to determine the chemical composition of the star and we do that with spectroscopy that works very similar to the mass spectrometer in all the TV shows. So we observe the light and it's sent through a prism and that gives us an absorption spectrum and we can measure the absorption lines that appear due to the wiggling of the atoms in the outer atmosphere of the star. And from the line strength we can determine how much of a given element is present in the star.
These stars are extremely rare as you can imagine since they are leftovers from this very early time from soon after the Big Bang. So it takes a lot of effort to find that needle in the galactic haystack. But first I actually have to make clear that these stars are found in our own Milky Way galaxy. They are super super old but they're actually very local. That complements the aspect that most people know about namely the very distant galaxies we call them high ratchet galaxies that are very, very far away and whose light has traveled for millions and billions of years to us. So when we finally detect it we see that galaxy as when it was very young. We have this complementary technique of using old stars and at some point the Milky Way has actually gobbled them up from wherever they're formed and so they are today located in our Milky Way very fairly close on astronomical standards. Only a few thousand light years away perhaps. And that is there where we look for them. It still takes a lot of work sifting through all these stars that formed recently like the Sun but we have a variety of telescopes in place that we regularly use to observe these stars. And it's a sequence of three steps going from smaller telescopes to intermediate size telescopes to the really big telescopes.
So at the moment I'm using mostly the largest telescopes in Chile. These ones are optical telescopes which means we observe visible light. And the telescope that I use there is called the Magellan telescope and it has a 6.5 meter mirror. It's quite big and impressive and I really love going there. Why do I do that? Well it really goes to the heart of what the job of an astronomer is. Collecting data. Sitting in a telescope staring at the night sky. And the fantastic thing in Chile is that the sky is absolutely dark. Actually that's not quite true. The surrounding Earth is really dark. The sky is super bright and it is absolutely marvelous and fantastic to just actually let the telescope do its job and go outside and look at the sky above you and you see the bright band of the Milky Way above you and the myriad of little lights in the sky. And you can even see the galactic center shining very bright and actually you can almost see your shadow. You definitely don't need any moon or any light to walk around. You're not going to walk into a tree or into a car or anything because the combined light from all the stars is so bright that you can orient yourself. This is absolutely fantastic and actually the best part of my job.
From our analysis and comparing our chemical abundance results – so the composition of these stars - with what is supposed to have come out of the very first stars we have actually learned that the very first stars were probably not as energetic in their deaths as previously assumed. And there's a lot of research going on in this area now to figure out what these first stars really were like and how energetic they were which has a lot of ramifications for how everything got started and what kind of role these first stars had in shaping this early time.
- With billions of stars in our galaxy, why should astronomers seek out the oldest ones?
- Age-dating stars is a complicated process, so astronomers use chemical compositions, telescopes, and prisms to determine the age of these ancient stars.
- Some telescopes used for this purpose are in extremely remote places, where you can observe the bright band of the Milky Way with the naked eye.
- We're more than stardust — we're made of the Big Bang itself - Big ... ›
- Scientists study 'weirdo particle' that predates the Sun. - Big Think ›
- Cosmic Riddle: How Can This Star Be Older Than the Universe ... ›
Join Pulitzer Prize-winning reporter and best-selling author Charles Duhigg as he interviews Victoria Montgomery Brown, co-founder and CEO of Big Think, live at 1pm EDT tomorrow.
A study looks at the performance benefits delivered by asthma drugs when they're taken by athletes who don't have asthma.
- One on hand, the most common health condition among Olympic athletes is asthma. On the other, asthmatic athletes regularly outperform their non-asthmatic counterparts.
- A new study assesses the performance-enhancement effects of asthma medication for non-asthmatics.
- The analysis looks at the effects of both allowed and banned asthma medications.
WADA uncertainty<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzNzU0OS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMDc4NjUwN30.fFTvRR0yJDLtFhaYiixh5Fa7NK1t1T4CzUM0Yh6KYiA/img.jpg?width=980" id="01b1b" class="rm-shortcode" data-rm-shortcode-id="2fd91a47d91e4d5083449b258a2fd63f" data-rm-shortcode-name="rebelmouse-image" alt="urine sample for drug test" />
Image source: joel bubble ben/Shutterstock<p>When inhaled β-agonists first came out just before the 1972 Olympics, they were immediately banned altogether by the WADA as possible doping substances. Over the years, the WADA has reexamined their use and refined the organization's stance, evidence of the thorniness of finding an equitable position regarding their use. As of January 2020, only three β-agonists are allowed — salbutamol, formoterol, and salmeterol —and only in inhaled form. Oral consumption appears to have a greater effect on performance.</p>
The study<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzNzU0Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MTIzMDQyMX0.Gk4v-7PCA7NohvJjw12L15p7SumPCY0tLdsSlMrLlGs/img.jpg?width=980" id="d3141" class="rm-shortcode" data-rm-shortcode-id="ebe7b30a315aeffcb4fe739095cf0767" data-rm-shortcode-name="rebelmouse-image" alt="runner at starting position on track" />
Image source: MinDof/Shutterstock<p>Of primary interest to the authors of the study is confirming and measuring the performance improvement to be gained from β-agonists when they're ingested by athletes who don't have asthma.</p><p>The researchers performed a meta-analysis of 34 existing studies documenting 44 randomized trials reporting on 472 participants. The pool of individuals included was broad, encompassing both untrained and elite athletes. In addition, lab tests, as opposed to actual competitions, tracked performance. The authors of the study therefore recommend taking its conclusions with just a grain of salt.</p><p>The effects of both WADA-banned and approved β-agonists were assessed.</p>
Approved β-agonists and non-asthmatic athletes<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzNzU1MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMzkxODk0M30.3RssFwk_tWkHRkEl_tIee02rdq2tLuAePifnngqcIr8/img.jpg?width=980" id="39a99" class="rm-shortcode" data-rm-shortcode-id="b1fe4a580c6d4f8a0fd021d7d6570e2a" data-rm-shortcode-name="rebelmouse-image" alt="vaulter clearing pole" />
Image source: Andrey Yurlov/Shutterstock<p>What the meta-analysis showed is that the currently approved β-agonists didn't significantly improve athletic performance among those without asthma — what very slight benefit they <em>may</em> produce is just enough to prompt the study's authors to write that "it is still uncertain whether approved doses improve anaerobic performance." They note that the tiny effect did increase slightly over multiple weeks of β-agonist intake.</p>
Banned β-agonist and non-asthmatic athletes<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzNzU1Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjI3ODU5Mn0.vyoxSE5EYjPGc2ZEbBN8d5F79nSEIiC6TUzTt0ycVqc/img.jpg?width=980" id="de095" class="rm-shortcode" data-rm-shortcode-id="02fdd42dfda8e3665a7b547bb88007ef" data-rm-shortcode-name="rebelmouse-image" alt="swimmer mid stroke" />
Image source: Nejron Photo/Shutterstock<p>The study found that for athletes without asthma, however, the use of currently banned β-agonists did indeed result in enhanced performance. The authors write, "Our meta-analysis shows that β2-agonists improve anaerobic performance by 5%, an improvement that would change the outcome of most athletic competitions."</p><p>That 5 percent is an average: 70-meter sprint performance was improved by 3 percent, while strength performance, MVC (maximal voluntary contraction), was improved by 6 percent.</p><p>The analysis also revealed that different results were produced by different methods of ingestion. The percentages cited above were seen when a β-agonist was ingested orally. The effect was less pronounced when the banned substances were inhaled.</p><p>Given the difference between the results for allowed and banned β-agonists, the study's conclusions suggest that the WADA has it about right, at least in terms of selection of allowable β-agonists, as well as the allowable dosage method.</p>
Takeaway<p>The study, say its authors, "should be of interest to WADA and anyone who is interested in equal opportunities in competitive sports." Its results clearly support vigilance, with the report concluding: "The use of β2-agonists in athletes should be regulated and limited to those with an asthma diagnosis documented with objective tests."</p>
Certain water beetles can escape from frogs after being consumed.
- A Japanese scientist shows that some beetles can wiggle out of frog's butts after being eaten whole.
- The research suggests the beetle can get out in as little as 7 minutes.
- Most of the beetles swallowed in the experiment survived with no complications after being excreted.
Richard Feynman once asked a silly question. Two MIT students just answered it.
Here's a fun experiment to try. Go to your pantry and see if you have a box of spaghetti. If you do, take out a noodle. Grab both ends of it and bend it until it breaks in half. How many pieces did it break into? If you got two large pieces and at least one small piece you're not alone.
But science loves a good challenge<p>The mystery remained unsolved until 2005, when French scientists <a href="http://www.lmm.jussieu.fr/~audoly/" target="_blank">Basile Audoly</a> and <a href="http://www.lmm.jussieu.fr/~neukirch/" target="_blank">Sebastien Neukirch </a>won an <a href="https://www.improbable.com/ig/" target="_blank">Ig Nobel Prize</a>, an award given to scientists for real work which is of a less serious nature than the discoveries that win Nobel prizes, for finally determining why this happens. <a href="http://www.lmm.jussieu.fr/spaghetti/audoly_neukirch_fragmentation.pdf" target="_blank">Their paper describing the effect is wonderfully funny to read</a>, as it takes such a banal issue so seriously. </p><p>They demonstrated that when a rod is bent past a certain point, such as when spaghetti is snapped in half by bending it at the ends, a "snapback effect" is created. This causes energy to reverberate from the initial break to other parts of the rod, often leading to a second break elsewhere.</p><p>While this settled the issue of <em>why </em>spaghetti noodles break into three or more pieces, it didn't establish if they always had to break this way. The question of if the snapback could be regulated remained unsettled.</p>
Physicists, being themselves, immediately wanted to try and break pasta into two pieces using this info<p><a href="https://roheiss.wordpress.com/fun/" target="_blank">Ronald Heisser</a> and <a href="https://math.mit.edu/directory/profile.php?pid=1787" target="_blank">Vishal Patil</a>, two graduate students currently at Cornell and MIT respectively, read about Feynman's night of noodle snapping in class and were inspired to try and find what could be done to make sure the pasta always broke in two.</p><p><a href="http://news.mit.edu/2018/mit-mathematicians-solve-age-old-spaghetti-mystery-0813" target="_blank">By placing the noodles in a special machine</a> built for the task and recording the bending with a high-powered camera, the young scientists were able to observe in extreme detail exactly what each change in their snapping method did to the pasta. After breaking more than 500 noodles, they found the solution.</p>
The apparatus the MIT researchers built specifically for the task of snapping hundreds of spaghetti sticks.
(Courtesy of the researchers)
What possible application could this have?<p>The snapback effect is not limited to uncooked pasta noodles and can be applied to rods of all sorts. The discovery of how to cleanly break them in two could be applied to future engineering projects.</p><p>Likewise, knowing how things fragment and fail is always handy to know when you're trying to build things. Carbon Nanotubes, <a href="https://bigthink.com/ideafeed/carbon-nanotube-space-elevator" target="_self">super strong cylinders often hailed as the building material of the future</a>, are also rods which can be better understood thanks to this odd experiment.</p><p>Sometimes big discoveries can be inspired by silly questions. If it hadn't been for Richard Feynman bending noodles seventy years ago, we wouldn't know what we know now about how energy is dispersed through rods and how to control their fracturing. While not all silly questions will lead to such a significant discovery, they can all help us learn.</p>
Several experts have weighed in on our sometimes morbid curiosity and fascination with true crime.
- True crime podcasts can get as many as 500,000 downloads per month. In the Top 100 Podcasts of 2020 list for Apple, several true crime podcasts ranked within the Top 20.
- Our fascination with true crime isn't just limited to podcasts, with Netflix documentaries like "Confessions of a Killer: The Ted Bundy Tapes" scoring high popularity with viewers.
- Several experts weigh in on our fascination with these stories with theories including fear-based adrenaline rushes and the inherent need to understand the human mind.
Why are we fascinated with true crime stories?<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzODA1MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MzkwOTAzOX0.7WqeWaf-odtEJV5XB2jdEG1uPU5d6Uaujw6iy6MKMbw/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="d99fc" class="rm-shortcode" data-rm-shortcode-id="e14d547e4d386925bad470882a823333" data-rm-shortcode-name="rebelmouse-image" alt="woman standing in front of crime scene notes" />
Several experts and psychologists weigh in on why we could be so fascinated by violence, destruction and true crime stories...
Photo by Motortion Films on Shutterstock<p>Several experts have weighed in on this topic over the years, as the spike in popularity of true crime media has continued at an astonishing rate.</p><p><strong>Psychopaths are charismatic.</strong> </p><p>One of the <a href="https://www.scienceofpeople.com/psychopath/#:~:text=Psychopathy%20researchers%20found%20that%20psychopaths,defer%20gratification%20and%20control%20behavior" target="_blank">defining qualities of a psychopath</a> is that they have "superficial charm and glibness", which could explain part of our fascination with podcasts, TV shows, and movies that cover the lives of famous serial killers like Ted Bundy.</p><p><strong>Our psychology demands we pay attention to things that could harm us.</strong></p><p>Psychology can play a large role in why we like what we like, and our fascination with true crime stories is no exception. When it comes to potential threats or things that could be threatening to humanity, perhaps we've been conditioned to pay those things extra attention. </p><p>According to Dr. John Mayer, a clinical psychologist at <a href="http://www.doctorondemand.com/" target="_blank">Doctor on Demand</a> who spoke about the process <a href="https://www.nbcnews.com/better/health/science-behind-why-we-can-t-look-away-disasters-ncna804966" target="_blank">in an interview with NBC News</a>, seeing destruction, disaster, or tragedy actually triggers survival instincts in us. </p><p>"A disaster enters into our awareness - this can be from a live source such as driving by a traffic accident or from watching a news report about a hurricane, a plane crash or any disaster," Mayer said. "This data from our perceptual system then stimulates the amygdala (the part of the brain responsible for emotions, survival tactics and memory). The amygdala then sends signals to the regions of the frontal cortex that are involved in analyzing and interpreting data. Next, the brain evaluates whether this data (awareness of the disaster) is a threat to you, thus judgment gets involved. As a result, the 'fight or flight' response is evoked." </p><p><strong>Could it just be morbid curiosity? </strong></p><p>Dr. Katherine Ramsland, Ph.D., a professor at De Sales University, explained <a href="https://www.bustle.com/p/why-are-people-so-obsessed-with-true-crime-experts-reveal-the-evolutionary-reasons-why-18138062" target="_blank">in an interview with Bustle</a>:</p><p>"Part of our love of true crime is based on something very natural: curiosity. People reading or watching a true crime story are engaged on several levels. They are curious about who would do this, they want to know the psychology of the bad guy, girl, or team. They want to know something about the abhorrent mind. They also love the puzzle - figuring out how it was done." </p><p><strong>Perhaps it's a way of facing our fears and planning our own reactions without risking immediate harm. </strong></p><p>In an interview with NBC News, psychiatrist Dr. David Henderson suggested that we may be fascinated with violence, destruction, or crime as a way of assessing how we would handle ourselves if put into that situation:</p><p style="margin-left: 20px;"><em>"Witnessing violence and destruction, whether it is in a novel, a movie, on TV or a real life scene playing out in front of us in real time, gives us the opportunity to confront our fears of death, pain, despair, degradation and annihilation while still feeling some level of safety. This sensation is sometimes experienced when we stand at the edge of the Grand Canyon or look through the glass at a ferocious lion at the zoo. We watch because we are allowed to ask ourselves ultimate questions with an intensity of emotion that is uncoupled from the true reality of the disaster: 'If I was in that situation, what would I do? How would I respond? Would I be the hero or the villain? Could I endure the pain? Would I have the strength to recover?' We play out the different scenarios in our head because it helps us to reconcile that which is uncontrollable with our need to remain in control."</em></p><p><strong>Psychologically, negative events activate our brains more than positive events. </strong></p><p><a href="http://psycnet.apa.org/doiLanding?doi=10.1037%2F0033-2909.134.3.383" target="_blank">A 2008 study</a> published by the American Psychological Association found that humans react to and learn more from negative experiences than we do positive ones. The term "negative bias" is the tendency to automatically give more attention (and meaning) to negative events and information more than positive events or information. </p><p><strong>A forced perspective may trigger empathy and act as a coping mechanism. </strong></p><p>Viewing destruction (or listening to/watching true crime stories) could be beneficial. According to Dr. Mayer, "the healthy mechanism of watching disasters is that it is a coping mechanism. We can become incubated emotionally by watching disasters and this helps us cope with hardships in our lives…" <a href="https://www.nbcnews.com/better/health/science-behind-why-we-can-t-look-away-disasters-ncna804966" target="_blank">Dr. Stephen Rosenburg points out</a>, however, that this empathetic response can also have a negative impact. "Being human and having empathy can make us feel worried or depressed."</p><p>Dr. Rosenberg goes on to explain that this can also impact the negativity bias. "We tend to think negatively to protect ourselves from the reality. If it turns out better, we're relieved. If it turns out worse, we're prepared." </p><p><strong>Perhaps the adrenaline of fear that comes from listening to or watching true crime can become addicting. </strong></p><p>Similarly to how people get a "runners high" from exercise or feel depressed when they have missed a scheduled run, the adrenaline that pumps during our consumption of true crime stories <a href="https://www.psychologytoday.com/us/blog/science-choice/201508/can-you-be-addicted-adrenaline" target="_blank">can become addictive</a>. According to sociology and criminology professor Scott Bonn, <a href="https://www.psychologytoday.com/us/blog/wicked-deeds/201605/the-delightful-guilty-pleasure-watching-true-crime-tv" target="_blank">in an interview with Psychology Today</a>: "The public is drawn to these stories because they trigger the most basic and powerful emotion in us all: fear."</p>