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.
Sure, Epicureans focused on seeking pleasure – but they also did so much more.
'The pursuit of Happiness' is a famous phrase in a famous document, the United States Declaration of Independence (1776). But few know that its author was inspired by an ancient Greek philosopher, Epicurus. Thomas Jefferson considered himself an Epicurean. He probably found the phrase in John Locke, who, like Thomas Hobbes, David Hume and Adam Smith, had also been influenced by Epicurus.
Nowadays, educated English-speaking urbanites might call you an epicure if you complain to a waiter about over-salted soup, and stoical if you don't. In the popular mind, an epicure fine-tunes pleasure, consuming beautifully, while a stoic lives a life of virtue, pleasure sublimated for good. But this doesn't do justice to Epicurus, who came closest of all the ancient philosophers to understanding the challenges of modern secular life.
Epicureanism competed with Stoicism to dominate Greek and Roman culture. Born in 341 BCE, only six years after Plato's death, Epicurus came of age at a good time to achieve influence. He was 18 when Alexander the Great died at the tail end of classical Greece – identified through its collection of independent city-states – and the emergence of the dynastic rule that spread across the Persian Empire. Zeno, who founded Stoicism in Cyprus and later taught it in Athens, lived during the same period. Later, the Roman Stoic Seneca both critiqued Epicurus and quoted him favourably.
Today, these two great contesting philosophies of ancient times have been reduced to attitudes about comfort and pleasure – will you send back the soup or not? That very misunderstanding tells me that Epicurean ideas won, hands down, though bowdlerised, without the full logic of the philosophy. Epicureans were concerned with how people felt. The Stoics focused on a hierarchy of value. If the Stoics had won, stoical would now mean noble and an epicure would be trivial.
Epicureans did focus on seeking pleasure – but they did so much more. They talked as much about reducing pain – and even more about being rational. They were interested in intelligent living, an idea that has evolved in our day to mean knowledgeable consumption. But equating knowing what will make you happiest with knowing the best wine means Epicurus is misunderstood.
The rationality he wedded to democracy relied on science. We now know Epicurus mainly through a poem, De rerum natura, or 'On the Nature of Things', a 7,400 line exposition by the Roman philosopher Lucretius, who lived c250 years after Epicurus. The poem was circulated only among a small number of people of letters until it was said to be rediscovered in the 15th century, when it radically challenged Christianity.
Its principles read as astonishingly modern, down to the physics. In six books, Lucretius states that everything is made of invisible particles, space and time are infinite, nature is an endless experiment, human society began as a battle to survive, there is no afterlife, religions are cruel delusions, and the universe has no clear purpose. The world is material – with a smidgen of free will. How should we live? Rationally, by dropping illusion. False ideas largely make us unhappy. If we minimise the pain they cause, we maximise our pleasure.
Secular moderns are so Epicurean that we might not hear this thunderclap. He didn't stress perfectionism or fine discriminations in pleasure – sending back the soup. He understood what the Buddhists call samsara, the suffering of endless craving. Pleasures are poisoned when we require that they do not end. So, for example, it is natural to enjoy sex, but sex will make you unhappy if you hope to possess your lover for all time.
Epicurus also seems uncannily modern in his attitude to parenting. Children are likely to bring at least as much pain as pleasure, he noted, so you might want to skip it. Modern couples who choose to be 'child-free' fit within the largely Epicurean culture we have today. Does it make sense to tell people to pursue their happiness and then expect them to take on decades of responsibility for other humans? Well, maybe, if you seek meaning. Our idea of meaning is something like the virtue embraced by the Stoics, who claimed it would bring you happiness.
Both the Stoics and the Epicureans understood that some good things are better than others. Thus you necessarily run into choices, and the need to forgo one good to protect or gain another. When you make those choices wisely, you'll be happier. But the Stoics think you'll be acting in line with a grand plan by a just grand designer, and the Epicureans don't.
As secular moderns, we pursue short-term happiness and achieve deeper pleasure in work well done. We seek the esteem of peers. It all makes sense in the light of science, which has documented that happiness for most of us arises from social ties – not the perfect rose garden or a closet of haute couture. Epicurus would not only appreciate the science, but was a big fan of friendship.
The Stoics and Epicureans diverge when it comes to politics. Epicurus thought politics brought only frustration. The Stoics believed that you should engage in politics as virtuously as you can. Here in the US where I live, half the country refrains from voting in non-presidential years, which seems Epicurean at heart.
Yet Epicurus was a democrat. In a garden on the outskirts of Athens, he set up a school scandalously open to women and slaves – a practice that his contemporaries saw as proof of his depravity. When Jefferson advocated education for American slaves, he might have had Epicurus in mind.
I imagine Epicurus would see far more consumption than necessary in my own American life and too little self-discipline. Above all, he wanted us to take responsibility for our choices. Here he is in his Letter to Menoeceus:
For it is not drinking bouts and continuous partying and enjoying boys and women, or consuming fish and the other dainties of an extravagant table, which produce the pleasant life, but sober calculation which searches out the reasons for every choice and avoidance and drives out the opinions which are the source of the greatest turmoil for men's souls.
Do you see the 'pursuit of happiness' as a tough research project and kick yourself when you're glum? You're Epicurean. We think of the Stoics as tougher, but they provided the comfort of faith. Accept your fate, they said. Epicurus said: It's a mess. Be smarter than the rest of them. How modern can you get?
Here's why you might eat greenhouse gases in the future.
- The company's protein powder, "Solein," is similar in form and taste to wheat flour.
- Based on a concept developed by NASA, the product has wide potential as a carbon-neutral source of protein.
- The man-made "meat" industry just got even more interesting.
When it comes to sniffing out whether a source is credible or not, even journalists can sometimes take the wrong approach.
- We all think that we're competent consumers of news media, but the research shows that even journalists struggle with identifying fact from fiction.
- When judging whether a piece of media is true or not, most of us focus too much on the source itself. Knowledge has a context, and it's important to look at that context when trying to validate a source.
- The opinions expressed in this video do not necessarily reflect the views of the Charles Koch Foundation, which encourages the expression of diverse viewpoints within a culture of civil discourse and mutual respect.