Is there a ninth planet lurking beyond the orbit of Neptune?
Astronomers have been observing strange gravitational patterns of a cluster of bodies known as “trans-Neptunian objects,” or TNOs, that could be explained by the presence of massive ninth planet in our solar system. The hypothetical planet, dubbed “Planet Nine,” would orbit our star at hundreds of times the distance between the Earth and the Sun.
It’s been a contentious topic, with some writing off the odd behavior of TNOs as being caused by a cluster of much smaller space rocks. Others predict that such a planet would be five times the mass of the Earth, orbiting our star at about 400 times the Earth’s distance from the Sun.
Finally, there’s the possibility that Planet Nine is actually a teeny-tiny black hole left over from the Big Bang. So tiny, in fact, that it’d only measure about five centimeters across — basically impossible to see with any kind of telescope.
“There has been a great deal of speculation concerning alternative explanations for the anomalous orbits observed in the outer solar system,” explained Amir Siraj, a Harvard undergraduate student, in a statement. “One of the ideas put forth was the possibility that Planet Nine could be a grapefruit-sized black hole with a mass of five to 10 times that of the Earth.”
So which is it then? In a new paper accepted into the The Astrophysical Journal Letters, Siraj, alongside a team of astronomers from Harvard University and the Black Hole Initiative outlined a newly developed method that could hopefully answer that question once and or all.
Their plan is to look for accretion flares given off as the tiny black hole gobbles up matter surrounding it. If they find some, it’d mean that Planet Nine is actually a black hole. “In the vicinity of a black hole, small bodies that approach it will melt as a result of heating from the background accretion of gas from the interstellar medium onto the black hole,” Siraj said.
“Because black holes are intrinsically dark, the radiation that matter emits on its way to the mouth of the black hole is our only way to illuminate this dark environment,” added Avi Loeb, professor of science at Harvard who was also involved in the research.
The team is placing their bets on the upcoming Legacy Survey of Space and Time (LSST) mission taking place at the Vera C. Rubin Observatory in Chile. Astronomers involved in the mission are hoping to answer questions about the nature of dark energy and dark matter as well as the formation and properties of planets in our solar system.
“LSST has a wide field of view, covering the entire sky again and again, and searching for transient flares,” Loeb said. “Other telescopes are good at pointing at a known target, but we do not know exactly where to look for Planet Nine. We only know the broad region in which it may reside.”
According to Loeb, the LSST’s “unprecedented depth” will be able to spot even the smallest of flares.
It’s not the only attempt to uncover the mysteries behind Planet Nine. Most recently, a different team of astronomers announced it’s hoping to launch a fleet of thousands of “nanospacecraft” to search for the mysterious object.
Unfortunately, that vision is still a moonshot, with cost estimates breaking the $1 billion mark — that is, if it’s even feasible from a technological standpoint in the first place.
READ MORE: Scientists propose plan to determine if Planet Nine is a primordial black hole [Harvard]
More on Planet Nine: A Black Hole May Be Orbiting Our Sun. This Guy Wants to Find It.
“America will never be destroyed from the outside. If we falter and lose our freedoms, it will be because we destroyed ourselves.”
~ Abraham Lincoln ~
This past autumn, a professor at Wuhan University named Jau Tang was hard at work piecing together a thruster prototype that, at first, sounds too good to be true.
The basic idea, he said in an interview, is that his device turns electricity directly into thrust — no fossil fuels required — by using microwaves to energize compressed air into a plasma state and shooting it out like a jet. Tang suggested, without a hint of self-aggrandizement, that it could likely be scaled up enough to fly large commercial passenger planes. Eventually, he says, it might even power spaceships.
Needless to say, these are grandiose claims. A thruster that doesn’t require tanks of fuel sounds suspiciously like science fiction — like the jets on Iron Man’s suit in the Marvel movies, for instance, or the thrusters that allow Doc Brown’s DeLorean to fly in “Back to the Future.”
But in Tang’s telling, his invention — let’s just call it a Tang Jet, which he worked on with Wuhan University collaborators Dan Ye and Jun Li — could have civilization-shifting potential here in the non-fictional world.
“Essentially, the goal of this technology is to try and use electricity and air to replace gasoline,” he said. “Global warming is a major threat to human civilization. Fossil fuel-free technology using microwave air plasma could be a solution.”
He anticipates this happening fast. In two years, he says, he thinks Tang Jets could power drones. In a decade, he’d like to see them fly a whole airplane.
That would all be awesome, obviously. But it’s difficult to evaluate whether Tang’s invention could ever scale up enough to become practical. And even if it did, there would be substantial energy requirements that could doom aerospace applications.
One thing’s for sure: If the tech works the way he hopes, the world will never be the same.
Tang’s curriculum vitae flits between a dazzling array of strikingly disparate academic topics, from 4D electron microscopy to quantum dot lasers, nanotechnology, artificial photosynthesis, and, of course, phase transitions and plasmonics.
He’s held several professorships, done research at Caltech and Bell Laboratories, published scores of widely-cited papers, edited several scientific journals, and won a variety of awards. He holds a U.S. patent for a device he calls a “synchrotron shutter,” designed to capture electrons traveling near the speed of light.
Tang says he first stumbled onto the idea for the plasma thruster when he was trying to create synthetic diamonds. As he tried to grow them using microwaves, he recalls, he started to wonder whether the same technology could be used to produce thrust.
Other huge stories, like the coronavirus pandemic and the baffling saga of Elon Musk naming his baby “X Æ A-12,” were sucking a lot of oxygen out of the news cycle in early May, when Tang announced his invention to the world. A few outlets picked up Tang’s story, including New Atlas, Popular Mechanics, and Ars Technica, but no journalist appears to have actually talked to him.
Because of that, there was little fanfare surrounding the sheer scope of his ambition for the technology — and it went overlooked that Tang sometimes sounds as though he’s invented a hammer and is now seeing a lot of things as nails.
After describing his plans to conquer aerospace with his new thruster, for instance, he starts to describe plans to take on the automotive industry as well — with jet-powered electric cars.
“I think the jet engine is more efficient than the electric motor, you can drive a car at much faster speeds,” he mused. “That’s what I have in mind: to combine the plasma jet engine with a turbine to drive a car.”
But you wouldn’t want to drive behind it, he warned, because you could be scorched by its fiery jet stream.
Over the course of our interview, Tang also brought up the possibilities of using the technology to build projectile weapons, launch spaceships, power boats, and even create a new type of stove for cooking. On that last point, Tang said that he’s already built a prototype kitchen stove powered by a microwave air plasma torch — but it’s so deafeningly loud that it sounds like a constant lightning strike.
Technically, the Tang Jet is an attempt to build a “plasma thruster,” a concept that’s periodically gained attention in scientific circles. Michael Heil, a retired aerospace and propulsion engineer with a long career of Air Force and NASA research, told Futurism that Tang’s research reminds him of several other attempts to build air propulsion tech that he’s encountered over the years.
Plasma thrusters like those that would power a Tang Jet have been around for a while. NASA first launched a satellite equipped with plasma thrusters back in 2006, but its capabilities are a far cry from what Tang is proposing with his research.
Engineers have long dreamed of a plasma jet-powered plane, but every attempt has been smacked down by the technological limitations of the day. For example, New Scientist reported in 2017 that a team from the Technical University of Berlin attempted to build a similar thruster — but like every attempt over the previous decade, their work never became useful outside of the lab.
The problems with these attempts aren’t so much faults with the theory — the concept of generating thrust with a plasma torch is fairly sound. Rather, issues begin to pop up when working out the logistics of building a vehicle that actually works.
Tang has little interest in commercializing the jet himself. Instead, he wants to demonstrate its merits in hopes that well-funded government leaders or titans of industry will be inspired to take the ideas and run with them.
“The steps toward realization of a full plasma jet engine would cost lots of money, time and energy,” he said. “Such investment is beyond our present resources. Such tasks should be taken by aerospace industries or governmental agencies.”
That’s a common mindset for scientists, said Christopher Combs, an aerodynamics researcher at the University of Texas at San Antonio.
“That’s what us academics do, we figure out the physics and say ‘Well I don’t want to make a product,’” he told Futurism. “It’s kind of a common refrain to see people in academia who have had something that gets a lot of attention.”
Though he’s intrigued by the underlying principles of the Tang Jet, Combs says it’s unlikely that it will scale up to the size needed to lift a plane — in other words, the same challenges that proved insurmountable to previous plasma thrusters will rear their heads once again. The current prototype, for perspective, only produces about 10 Newtons of thrust — about the same as a medium-sized model rocket.
“You’re talking about scaling something by five orders of magnitude — more than 100,000 times!” Combs said. “Which almost never works linearly. Lots of engineering happens in the middle.”
And even if it were to scale perfectly, there’s the issue of power. Iron Man’s suit was powered by an “Arc Reactor,” and the flying DeLorean was powered by a “Mr. Fusion” unit that turned household trash into more than a gigawatt of power — both of which, unfortunately, are fictional.
Fossil fuels store vastly more energy by weight than batteries, and that’s unlikely to change any time soon. And that’s too bad, because the Tang Jet needs a whole lot of power.
According to a paper Tang and his collaborators published about the thruster prototype in the journal AIP Advances in May, the technology produces about 28 Newtons of thrust per kilowatt of power. The engines on the Airbus A320, a common commercial jet, produce about 220,000 Newtons of thrust combined, meaning that a comparably-sized jet plane powered by Tang Jets would require more than 7,800 kilowatts.
For perspective, that would mean loading an aircraft up with more than 570 Tesla Powerwall 2 units for a single hour of flight — an impractical load, especially because the A320’s payload could only carry about 130 of the giant battery units. Long story short, no existing battery tech could provide enough juice.
“Does this thing just become a flying Tesla battery?” Combs said. “With the weight of these batteries, you don’t have room for anything else.”
The battery weight issue doesn’t doom the Tang Jet, but it pushes options for its power source into the fringe. Tang is banking on improvements to battery technology over the next years and decades; those Technical University of Berlin researchers speculated about nuclear fusion. Unfortunately, any possible answers could be decades away or impossible.
It is worth noting that there exist compact nuclear fission reactors, like Russia’s KLT-40S, that produce enough power and weigh little enough that they could fit in a passenger plane or rocket.
But the safety and environmental implications of nuclear-powered aircraft are grim, and Heil was quick to point out that generating enough power isn’t the only problem facing a Tang Jet. Actually getting the electricity from the power source to the thrusters would pose its own difficulties, perhaps requiring superconducting materials that don’t exist yet.
“You need power to generate thrust. And how do you move that power around on the aircraft?” Heil said. “Moving and controlling megawatts from the reactor to the jet is a huge challenge. You have to use big thick copper wires, that adds a lot of weight.”
Overall, both Combs and Heil questioned the feasibility of a practical Tang Jet based on the technology we have today. Without a quick fix to the energy problem, it’s certainly a tall order.
But both said they were fascinated by the research and hoped to see future progress. They also pointed out that a plasma thruster could be useful for pushing satellites or spacecraft that are already in orbit — though at that point it would need to bring propellant with it rather than using atmospheric air, since there’d be none in the vacuum of space.
The bottom line, Heil and Combs agreed, is that we won’t have a firmer grasp of the future of the tech until Tang’s colleagues have evaluated and experimented with it.
“I’m rooting for this, and I’d love to see it pan out,” Combs said. “But the scientist in me has some questions and some concerns.”
More on Tang’s plasma jets: Scientists Create Jet Engine Powered by Only Electricity
“The shadow moves. It’s flapping like the wings of a bird!”
NASA’s Hubble Space Telescope just caught the “bat shadow” of a newborn star moving — a sight the space agency evocatively compared to a pair of flapping bat wings.
“The shadow moves. It’s flapping like the wings of a bird!” Klaus Pontoppidan, an astronomer at the Space Telescope Science Institute (STScI) in Baltimore, and lead author of a paper about the discovery in the Astrophysical Journal, said in a statement.
The star, called HBC 672 and located some 1,400 light years away in the Serpent nebula, is just one or two million years old — practically a baby in cosmic terms. It casts the shadow due to a warped and flared disk surrounding it.
“You have a star that is surrounded by a disk, and the disk is not like Saturn’s rings — it’s not flat,” explained Pontoppidan. “It’s puffed up. And so that means that if the light from the star goes straight up, it can continue straight up — it’s not blocked by anything.”
But if the ring does block it, the light “doesn’t get out and it casts a shadow,” he added.
The disk surrounding the young star is likely made out of gas, dust and rock and has two peaks on opposite ends, like a horse saddle. Light cast through this ring ends up looking like a pair of flapping wings.
The disk itself is too small and far away for Hubble to observe it directly, so the team had to resort to examining its massive shadow.
The astronomers suspect a planet in the star’s orbit could be warping and shifting the shape of the ring, and therefore the movement of its shadow. Such a planet would take an estimated 180 Earth-days to circle its parent star.
The star may be extremely young, but its ring of rock and dust is enormous. The size of just the shadow alone would be hundreds of times the size our entire solar system, according to NASA. Light would take more than a month to travel that distance.
By taking additional pictures using filters, the team was able to create a gorgeous, colored image of the star and its “bat shadow.”
READ MORE: Hubble Sees Cosmic Flapping ‘Bat Shadow’ [NASA]
What is AI?
From SIRI to self-driving cars, artificial intelligence (AI) is progressing rapidly. While science fiction often portrays AI as robots with human-like characteristics, AI can encompass anything from Google’s search algorithms to IBM’s Watson to autonomous weapons.
Artificial intelligence today is properly known as narrow AI (or weak AI), in that it is designed to perform a narrow task (e.g. only facial recognition or only internet searches or only driving a car). However, the long-term goal of many researchers is to create general AI (AGI or strong AI). While narrow AI may outperform humans at whatever its specific task is, like playing chess or solving equations, AGI would outperform humans at nearly every cognitive task.
Why research AI safety?
In the near term, the goal of keeping AI’s impact on society beneficial motivates research in many areas, from economics and law to technical topics such as verification, validity, security and control. Whereas it may be little more than a minor nuisance if your laptop crashes or gets hacked, it becomes all the more important that an AI system does what you want it to do if it controls your car, your airplane, your pacemaker, your automated trading system or your power grid. Another short-term challenge is preventing a devastating arms race in lethal autonomous weapons.
How can AI be dangerous?
Most researchers agree that a superintelligent AI is unlikely to exhibit human emotions like love or hate, and that there is no reason to expect AI to become intentionally benevolent or malevolent. Instead, when considering how AI might become a risk, experts think two scenarios most likely:
- The AI is programmed to do something devastating: Autonomous weapons are artificial intelligence systems that are programmed to kill. In the hands of the wrong person, these weapons could easily cause mass casualties. Moreover, an AI arms race could inadvertently lead to an AI war that also results in mass casualties. To avoid being thwarted by the enemy, these weapons would be designed to be extremely difficult to simply “turn off,” so humans could plausibly lose control of such a situation. This risk is one that’s present even with narrow AI, but grows as levels of AI intelligence and autonomy increase.
- The AI is programmed to do something beneficial, but it develops a destructive method for achieving its goal: This can happen whenever we fail to fully align the AI’s goals with ours, which is strikingly difficult. If you ask an obedient intelligent car to take you to the airport as fast as possible, it might get you there chased by helicopters and covered in vomit, doing not what you wanted but literally what you asked for. If a superintelligent system is tasked with a ambitious geoengineering project, it might wreak havoc with our ecosystem as a side effect, and view human attempts to stop it as a threat to be met. More Information – HERE