How ‘The Goblin’ may unravel the mystery of Planet Nine
Around Halloween in 2015, astronomers discovered 'The Goblin'. Now, it's leading us to what some call Planet X.
Dr. Michelle Thaller is an astronomer who studies binary stars and the life cycles of stars. She is Assistant Director of Science Communication at NASA. She went to college at Harvard University, completed a post-doctoral research fellowship at the California Institute of Technology (Caltech) in Pasadena, Calif. then started working for the Jet Propulsion Laboratory's (JPL) Spitzer Space Telescope. After a hugely successful mission, she moved on to NASA's Goddard Space Flight Center (GSFC), in the Washington D.C. area. In her off-hours often puts on about 30lbs of Elizabethan garb and performs intricate Renaissance dances. For more information, visit NASA.
MICHELLE THALLER: It may surprise you to know that we are still learning about our own solar system; even the question about how many planets are there is kind of a funny one—take Pluto.
Pluto was classified as a dwarf planet, and there are other dwarf planets as well. In fact, the largest of the asteroids, Ceres, is now classified as a dwarf planet. A lot of these dwarf planets actually exist farther beyond the orbit of Pluto, and we're just finding them now. And one of my favorite discoveries recently has been something called The Goblin. Now, The Goblin is a dwarf planet—it's actually much smaller than Pluto; it's only about a fifth of the diameter of Pluto, and it is really, really far out there. It's in a highly elongated orbit; the closest it ever gets is about twice as far away as Pluto is, and the farthest it gets is about 2,300 times the distance from the Earth to the Sun; it goes way, way, way out there. This orbit takes it about 40,000 years to go once around the Sun. It's really, really incredible. It doesn't surprise me that these objects are only recently being discovered because most of them are so distant. They are so faint, and if they're at the very far part of their orbit they're moving very, very slowly—very, very hard to detect.
Now, The Goblin is really interesting in a number of ways. One of the things that I love about it is that it does actually seem to hint that there may be something larger out there—we've been noticing this for the last couple of years. These distant icy bodies are called Kuiper Belt objects, and often they're on elongated orbits that come close to the Sun—and by close I mean about the orbit of Pluto and then much, much farther away into the very outer reaches of the solar system. We now know of dozens of these objects, and there are probably many more out there we haven't discovered. The interesting thing is we began to observe how their orbits were aligned in our solar system, and there's something called perihelion, which is the closest pass an object makes to the Sun. And amazingly, all of these objects all over this sky seem to have perihelions—closest approaches to the Sun—that were beautifully lined up together. There is no reason for that to be the case. If they were independent orbiting bodies there's no way their closest approach to the Sun should match. So the idea is there's a larger body out there somewhere, a larger planet, and as it orbits it lines up, kind of shepherds all these smaller objects into its orbit. The evidence for this really is pretty compelling. We don't know of any other way to explain the lined up orbits of these Kuiper Belt objects. So then the question is: Where is this bigger planet?
Our estimates put it at least three to five times the mass of the Earth, maybe even a little bit more massive than that. It could be something on the order of the size of Neptune. This is a big planet we're talking about, and honestly, it's a little embarrassing that we've missed an entire big planet in our solar system. We are now so good at detecting planets we can see them around other stars, so how is it we've missed this planet? Well, if it really is very far away from us in its orbit right now; even a big planet would be tiny to the most powerful telescopes, so we could have missed it. It also would be moving so slowly that maybe we didn't notice that it was a planet. Maybe people assumed it was a distant star. So telescopes all over the world are scanning the sky for any sense that there's an object out there moving very, very slowly that could be evidence of this giant planet.
Judging from the way these orbits are lined up I think it is very likely there could be a big planet out there, and I am going to be really happy when we have something else to add to our knowledge of the solar system.
There's also something kind of wonderful happening January 1st of 2019, it's coming up pretty soon—and that is that we're going to visit one of these Kuiper Belt objects for the very first time. The New Horizons spacecraft a couple years ago flew by Pluto. Hopefully, you remember the beautiful images of Pluto that have returned. Then we aimed it at one of these distant Kuiper Belt objects. We call it MU69, or it's been nicknamed Ultima Thule, which means "farthest frontier."
Now, hopefully, you remember the New Horizons spacecraft from its spectacular flyby of Pluto a couple of years ago. So after it flew by Pluto we aimed it even farther out to encounter one of these distant icy objects. It's the first time we will ever see what one of these objects is like. After January we will finally have a picture of a part of the solar system we've never seen before.
- 'The Goblin' is a dwarf planet known more formally as '2015 TG387'. It was nicknamed The Goblin because of the 'TG' in its title, and because of the time of year it was discovered: Halloween.
- The Goblin has an extreme orbit: far-flung and elongated. It takes 40,000 years to make a complete orbit around the Sun.
- This cosmic anomaly is a clue. Astronomers hypothesize that The Goblin is being pulled into the gravitational field of a 'Super-Earth' planet in our solar system that is believed to exist but has never been seen: the mysterious Planet Nine or Planet X.
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Research suggests that aging affects a brain circuit critical for learning and decision-making.
As people age, they often lose their motivation to learn new things or engage in everyday activities. In a study of mice, MIT neuroscientists have now identified a brain circuit that is critical for maintaining this kind of motivation.
Researchers find a key clue to the evolution of bony fish and tetrapods.
- A new study says solar and lunar tide impacts led to the evolution of bony fish and tetrapods.
- The scientists show that tides created tidal pools, stranding fish and forcing them to get out of the water.
- The researchers ran computer simulations to get their results.
Neil deGrasse Tyson Explains the Tides<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="9913a65f847775722d7c23d40d78938b"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/dBwNadry-TU?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
A study finds 1.8 billion trees and shrubs in the Sahara desert.
- AI analysis of satellite images sees trees and shrubs where human eyes can't.
- At the western edge of the Sahara is more significant vegetation than previously suspected.
- Machine learning trained to recognize trees completed the detailed study in hours.
Why this matters<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU2MDQ1OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzOTkyODg5NX0.O3S2DRTyAxh-JZqxGKj9KkC6ndZAloEh4hKhpcyeFDQ/img.jpg?width=980" id="3770d" class="rm-shortcode" data-rm-shortcode-id="3c27b79d4c0600fb6ebb82e650cabec0" data-rm-shortcode-name="rebelmouse-image" />
Area in which trees were located
Credit: University of Copenhagen<p>As important as trees are in fighting climate change, scientists need to know what trees there are, and where, and the study's finding represents a significant addition to the global tree inventory.</p><p>The vegetation Brandt and his colleagues have identified is in the Western Sahara, a region of about 1.3 million square kilometers that includes the desert, <a href="https://en.wikipedia.org/wiki/Sahel" target="_blank">the Sahel</a>, and the <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/subhumid-zones" target="_blank" rel="noopener noreferrer">sub-humid zones</a> of West Africa.</p><p>These trees and shrubs have been left out of previous tabulations of carbon-processing worldwide forests. Says Brandt, "Trees outside of forested areas are usually not included in climate models, and we know very little about their carbon stocks. They are basically a white spot on maps and an unknown component in the global carbon cycle."</p><p>In addition to being valuable climate-change information, the research can help facilitate strategic development of the region in which the vegetation grows due to a greater understanding of local ecosystems.</p>
Trained for trees<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU2MDQ3MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNTk5NTI3NH0.fR-n1I2DHBIRPLvXv4g0PVM8ciZwSLWorBUUw2wc-Vk/img.jpg?width=980" id="e02c0" class="rm-shortcode" data-rm-shortcode-id="79955b13661dca8b6e19007935129af1" data-rm-shortcode-name="rebelmouse-image" />
Credit: Martin Brandt/University of Copenhagen<p>There's been an assumption that there's hardly enough vegetation outside of forested areas to be worth counting in areas such as this one. As a result the study represents the first time a significant number of trees — likely in the hundreds of millions when shrubs are subtracted from the overall figure — have been catalogued in the drylands region.</p><p>Members of the university's Department of Computer Science trained a machine-learning module to recognize trees by feeding it thousands of pictures of them. This training left the AI be capable of spotting trees in the tiny details of satellite images supplied by NASA. The task took the AI just hours — it would take a human years to perform an equivalent analysis.</p><p>"This technology has enormous potential when it comes to documenting changes on a global scale and ultimately, in contributing towards global climate goals," says co-author Christian Igel. "It is a motivation for us to develop this type of beneficial artificial intelligence."</p><p>"Indeed," says Brandt says, "I think it marks the beginning of a new scientific era."</p>
Looking ahead and beyond<p>The researchers hope to further refine their AI to provide a more detailed accounting of the trees it identifies in satellite photos.</p><p>The study's senior author, Rasmus Fensholt, says, "we are also interested in using satellites to determine tree species, as tree types are significant in relation to their value to local populations who use wood resources as part of their livelihoods. Trees and their fruit are consumed by both livestock and humans, and when preserved in the fields, trees have a positive effect on crop yields because they improve the balance of water and nutrients."</p><p>Ahead is an expansion of the team's tree hunt to a larger area of Africa, with the long-term goal being the creation of a more comprehensive and accurate global database of trees that grow beyond the boundaries of forests.</p>
Most people believe themselves to be less at risk from COVID-19 than others similar to them, according to a recent UCL survey conducted in the U.S.
- A study surveying 1,145 people in the U.S. found that the majority of people believed that they were less likely to catch the virus than the average person, regardless of the person's age or gender.
- The most effective way to counter the damaging effects of cognitive bias in the context of COVID-19 may be by calling on empathy in individuals.
- The dangerous effects of optimism bias may be compounded by confirmation bias, salience bias, and internet echo chambers.
Optimism bias<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU5OTg2OS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzMTAzNDM0Mn0.vRtlUDOpCnC_ZOdjxZUpRL5J9fnBeITmXXIPOMXOzhg/img.jpg?width=1245&coordinates=0%2C2291%2C0%2C1908&height=700" id="abbcf" class="rm-shortcode" data-rm-shortcode-id="ff0569ffedf799d7a1237068dc1ee72f" data-rm-shortcode-name="rebelmouse-image" alt="smiley paint on gray ground in front of people" />Photo by Nathan Dumlao on Unsplash<p>Most people have a tendency to overestimate the chances of experiencing a positive (like getting a promotion), and underestimate the likelihood of experiencing a negative event (like getting robbed or sick). Typically a benign — even beneficial — human quirk, the "optimism bias" could be contributing to the spread of coronavirus according to behavioral psychologists.</p><p>Experts argue that it has caused people to discount their individual chances of contracting COVID-19, despite being aware of its risk to the rest of the population. A study that was conducted over three phases this year surveying 1,145 people in the U.S. found that the majority of people believed that they were less likely to catch the virus than the average person is, regardless of the person's age or gender. </p><p>"This is very typical of what optimism bias is," Tali Sharot, a cognitive neuroscientist at University College London and lead author of the study, <a href="https://www.cnbc.com/2020/10/22/why-optimism-bias-could-be-unhelpful-in-a-pandemic-say-psychologists.html" target="_blank" rel="noopener noreferrer">told CNBC Make It</a>. "You usually believe that your likelihood of experiencing negative events is lower than people like you, and the likelihood of you experiencing positive events is higher than other people like you."</p><p>According to Sharot, optimism bias is a product of our tendency to vividly imagine positive future events and attribute more probability to them happening. </p><p>In certain circumstances, such as in our jobs and relationships, this can be beneficial by encouraging us to behave in ways that may contribute to positive outcomes, thus becoming a self-fulfilling prophecy. But we're in a pandemic, and it's having a concerning impact on our ability to assess risk and react appropriately. As time goes on and COVID-19 cases <a href="https://www.cnn.com/2020/10/26/health/us-coronavirus-monday/index.html" target="_blank" rel="noopener noreferrer">continue to rise and spread</a> the threat of the virus is becoming a background hum to everyday life making this bias worse. </p><p>"I think now the risk is greater because we have gotten used to this threat. And when you get used to a threat you underestimate it even more," said Sharot.</p><p>The United States is now reporting the greatest number of cases it's seen to date, with a seven-day average of daily new cases reaching 68,767 on Sunday, according to data from Johns Hopkins University. </p>
Other menacing biases<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU5OTg3Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2MzA1OTMwOX0.f68UAZY--fN5yJ_26v7OjhQG5Ieda_HQx_iDF5NKHJI/img.jpg?width=1245&coordinates=0%2C30%2C0%2C31&height=700" id="79c78" class="rm-shortcode" data-rm-shortcode-id="8b155c7f4503e53d756c1451be9874c8" data-rm-shortcode-name="rebelmouse-image" />
Credit: Michael Siluk/Education Images/Universal Images Group via Getty Images<p>Optimism bias may be compounded by <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7144592/" target="_blank">confirmation bias</a>, or the tendency to interpret new information as confirmation of one's existing beliefs or theories while disregarding information that contradicts one's preferred narrative of reality. Salience bias is also at play, leading people to underplay or discount the threat of something they cannot see such as a microscopic virus or sick people in the hospital.</p><p>Additionally, internet echo chambers exacerbate these cognitive biases. When others share our viewpoints, our biases are typically inflated, and it's never been easier to curate our social circles with networks of people who do exactly that. This feeds into the tribalism and polarization that has added to the challenges of getting a majority of the U.S. population to comply with virus safety measures. Think, for example, how the act of <a href="https://bigthink.com/coronavirus/face-masks-transmission" target="_blank">wearing a mask has become politicized</a> in the U.S. as a perceived badge as to which group one belongs to, masks often being associated with liberal-leaning people and no masks (<a href="https://bigthink.com/coronavirus/christian-nationalism" target="_blank">anti-maskers</a>) being associated with the far-right. </p>