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.
Can Impossible Foods beat other brands — like Beyond Meat and Tyson — in the war to dominate the alternative meat industry?
- The Impossible Burger will be available in 27 Gelson's Markets stores in Southern California starting Sept. 20.
- Beyond Meat and Impossible Foods sell plant-based burgers in restaurants, but only Beyond Meat sells products in grocery stores.
- Tyson could begin to edge out these smaller companies with its unique meat product that contains plant and animal components, appealing to health-conscious "flexitarians."
Most elderly individuals' brains degrade over time, but some match — or even outperform — younger individuals on cognitive tests.
- "Super-agers" seem to escape the decline in cognitive function that affects most of the elderly population.
- New research suggests this is because of higher functional connectivity in key brain networks.
- It's not clear what the specific reason for this is, but research has uncovered several activities that encourage greater brain health in old age.
At some point in our 20s or 30s, something starts to change in our brains. They begin to shrink a little bit. The myelin that insulates our nerves begins to lose some of its integrity. Fewer and fewer chemical messages get sent as our brains make fewer neurotransmitters.
As we get older, these processes increase. Brain weight decreases by about 5 percent per decade after 40. The frontal lobe and hippocampus — areas related to memory encoding — begin to shrink mainly around 60 or 70. But this is just an unfortunate reality; you can't always be young, and things will begin to break down eventually. That's part of the reason why some individuals think that we should all hope for a life that ends by 75, before the worst effects of time sink in.
But this might be a touch premature. Some lucky individuals seem to resist these destructive forces working on our brains. In cognitive tests, these 80-year-old "super-agers" perform just as well as individuals in their 20s.
Just as sharp as the whippersnappers
To find out what's behind the phenomenon of super-agers, researchers conducted a study examining the brains and cognitive performances of two groups: 41 young adults between the ages of 18 and 35 and 40 older adults between the ages of 60 and 80.
First, the researchers administered a series of cognitive tests, like the California Verbal Learning Test (CVLT) and the Trail Making Test (TMT). Seventeen members of the older group scored at or above the mean scores of the younger group. That is, these 17 could be considered super-agers, performing at the same level as the younger study participants. Aside from these individuals, members of the older group tended to perform less well on the cognitive tests. Then, the researchers scanned all participants' brains in an fMRI, paying special attention to two portions of the brain: the default mode network and the salience network.
The default mode network is, as its name might suggest, a series of brain regions that are active by default — when we're not engaged in a task, they tend to show higher levels of activity. It also appears to be very related to thinking about one's self, thinking about others, as well as aspects of memory and thinking about the future.
The salience network is another network of brain regions, so named because it appears deeply linked to detecting and integrating salient emotional and sensory stimuli. (In neuroscience, saliency refers to how much an item "sticks out"). Both of these networks are also extremely important to overall cognitive function, and in super-agers, the activity in these networks was more coordinated than in their peers.
An image of the brain highlighting the regions associated with the default mode network.
How to ensure brain health in old age
While prior research has identified some genetic influences on how "gracefully" the brain ages, there are likely activities that can encourage brain health. "We hope to identify things we can prescribe for people that would help them be more like a superager," said Bradford Dickerson, one of the researchers in this study, in a statement. "It's not as likely to be a pill as more likely to be recommendations for lifestyle, diet, and exercise. That's one of the long-term goals of this study — to try to help people become superagers if they want to."
To date, there is some preliminary evidence of ways that you can keep your brain younger longer. For instance, more education and a cognitively demanding job predicts having higher cognitive abilities in old age. Generally speaking, the adage of "use it or lose it" appears to hold true; having a cognitively active lifestyle helps to protect your brain in old age. So, it might be tempting to fill your golden years with beer and reruns of CSI, but it's unlikely to help you keep your edge.
Aside from these intuitive ways to keep your brain healthy, regular exercise appears to boost cognitive health in old age, as Dickinson mentioned. Diet is also a protective factor, especially for diets delivering omega-3 fatty acids (which can be found in fish oil), polyphenols (found in dark chocolate!), vitamin D (egg yolks and sunlight), and the B vitamins (meat, eggs, and legumes). There's also evidence that having a healthy social life in old age can protect against cognitive decline.
For many, the physical decline associated with old age is an expected side effect of a life well-lived. But the idea that our intellect will also degrade can be a much scarier reality. Fortunately, the existence of super-agers shows that at the very least, we don't have to accept cognitive decline without a fight.
The move comes one day before more than 1,500 Amazon employees are set to walk off the job as part of the global climate strikes.
- Amazon CEO Jeff Bezos announced on Thursday plans to swiftly combat climate change.
- Some parts of the plan include becoming carbon neutral by 2040, buying 100,000 electric delivery vans and reaching zero emissions by 2030.
- Some Amazon employees say the pledge is good but doesn't go far enough.