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SciTechPress

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  1. I just read the following on another forum talking about the long term prospects for Earth: "...And we’re cooling off down below at a far faster rate (about 5x) than the sun is warming up. The point is… in about a billion years… maybe 1.5 (we’re still measuring and guessing to be honest)… the Earth will be very cold, with most of our remaining water trapped permanently below the surface as part of the lithosphere. We won’t be much better off than mars is now. And as the dynamo at the center of the earth wanes (and it is), the magnetic field that keeps the sun from punishing our atmosphere worse than it already does will no longer be up to the job… so not only will the crust beneath our feet by cold, but the air will be a looooot thinner (and thus also cold.) Radiation will get through much more easily and you’ll be lucky to see an equatorial summer’s afternoon reach 10C. Of course, dry as as a bone as it would be, you probably wouldn’t see any liquid water anyways… not even at high noon." ---------------------------------------------------- So ... Could Global Warming end up being a good thing for planet Earth long term?
  2. The humble pine cone is more than a holiday decoration. It's an ancient form of tree sex. Flowers may be faster and showier, but the largest living things in the world? The oldest? They all reproduce with cones.
  3. How to make hobby rocket “sugar motors” using sugar and kitty litter, that shoot up over 2,300 feet high, and cost less than $0.50 to make.
  4. Our star will expand into a red giant in about 4.5billion years. At this point will extend to 0.8AU or more. 500,000 years later it will shed the outer layers of gas(think of it like an onion) and the end result will be two things. 1: a planetary nebula 2: a White Dwarf A white dwarf is the core of the star and since it was the core, it is still very very very hot. It can easily be about 40,000K which is about 4000 x the boiling point of water. Since these objects are no longer generating heat they’re cooling down. But since space has no air they only way they cool down is via radiating the heat out. The time it will take for a white dwarf to cool to 2K is over 10,000,000,000,000 years, yup. They will take longer to cool than the universe has been around for. In the future when their is not enough Hydrogen to form any new stars the only thing that will be left is these white dwarfs. Once these reach 0K the universe will be dead, black.
  5. National and international efforts to develop new sources of carbon-free energy are exploring a nuclear power concept first introduced in the 1950s and 1960s: the Molten Salt Reactor. This design is vastly different from our current light water nuclear power plant and is inspiring a fresh look at the technology. Researchers at Pacific Northwest National Laboratory are working on many solutions necessary for the design, construction, and operation of a full-scale molten salt reactor. We have expertise in radiochemistry and real-time online monitoring, as well as materials design and performance testing.
  6. Dude! Poison nerve agent?! Seriously? Hold my beer. or I enjoyed those dismembering pics you sent. Thank you! or Do we know how to take care of pesky journalists or what?
  7. Yes. Very unfortunate move. How many cases of Carpal Tunnel syndrome has he caused? How much has he slowed down the entire world by stealing 2 seconds from every living typing person worldwide since the dawn of the PC? How can we collectively tax Microsoft for this lost time and productivity?
  8. The NBA has signed deals with sports data providers Genius Sports Group and Sportradar to provide betting data to U.S. sportsbooks. The partnership is the first of its kind for a major U.S. sports league. Promoting in-game betting We're in the second quarter—will Lebron James make his next free throw? It's halftime—do you want to bet the "over," now bumped up 15 points given that high-scoring first half? This type of live gambling requires fast and reliable data transmission, which is at the crux of the NBA's new partnerships. NBA Commissioner Adam Silver wants the league to earn a cut from wagers on its games, but that's going to require legislative action. So...selling proprietary data might be the next best way to make a buck on the growing trend of live betting. Need proof? In the U.K., more money is bet during a match than before it.
  9. Yesterday, New Zealand blocked Chinese telecom firm Huawei from building out a 5G network in the country—after Australia did the same in August. New Zealand intelligence officials informed a major NZ carrier that using Huawei's 5G equipment would "raise significant national security risks." About the risks: Some countries worry that Huawei will use its powerful technology to spy on or disrupt communications on behalf of the Chinese government. The threat is so real that the U.S. government has reportedly started an "extraordinary" effort to encourage allies to block Huawei (the largest telecom equipment maker in the world) from supplying 5G infrastructure. As the U.S.-China conflict rages on, we are seeing a divide between countries that are comfortable with using next-gen Chinese tech...and ones that aren't. On Monday, Papua New Guinea said it's sticking to its deal with Huawei.
  10. I had that same bike back in the day.
  11. Add this one to the long list of Star Trek Prophecies come true: Wouldn't this be very similar to their "impulse drive"? Smiling.
  12. Another Star Trek prophecy comes true..... The Impulse drive! :-)
  13. Imagine an aircraft engine that has no moving parts, produces no harmful exhaust and makes no noise. That's what researchers at the Massachusetts Institute of Technology (MIT) in the US have created by adapting a technology previously only used in spacecraft so it can power flight over the Earth. Ion drives have been used on spacecraft since the 1960s and work by firing out a stream of charged particles that propel the vessel forward. As well as being carbon neutral, they are less likely to go wrong and cheaper to maintain than conventional engines because they have no propellers, turbines or fuel pumps to break down. The only problem was that, in Earth's gravity, the thrust produced by the drive wasn't enough to overcome the weight of the batteries needed to power them. Until now. The timely new research, published in Nature, paves the way for the possibility of silent drones in the very near future. With further advances in materials and power conversion, silent crewed aircraft and eventually commercial flights could also be on the horizon. In fact, this breakthrough could be the first step in changing how we all fly around the world in the future. All aircraft engines work by pushing something backwards so that the craft moves forward. Usually this is air, whether cold air driven by electric propellers or hot air fired out by jet engines. Ion propulsion instead sends out charged particles or ions generated in the gap between two electrodes with a high voltage inbetween. The ions interact with the air, creating an ionic wind that is sent backwards, propelling the aircraft forward. As with propeller-driven solar powered aircraft, ion drive craft are powered by electricity and so don't need to carry fuel, other than batteries filled with charged particles. The new research shows that, with some clever modifications to the battery setup and the way the electrical power is converted, it's possible to reduce the battery weight enough to make this technology fly. Compromise design A craft with an ion drive also needs a large front area to generate the ionic wind in the right way. But this would usually make the aircraft heavier, so the researchers had to balance these conflicting limitations. They designed a wingspan that was small enough to reduce risks and make the testing cheaper and easier, while being large enough to use standard remote control components. The researchers flew ten flights using an aircraft with a 5-metre wingspan, weighing less than 2.5 kilograms. They were able to fly it for up to 9 seconds over a distance of 45 metres at a speed of 5 metres a second. The craft needed around 20 seconds to build up its power and was then launched using a mechanical bungee system. While this flight time and distance might not seem like much, the researchers point out that they're actually similar to the those of the first flight of aeroplane inventors the Wright Brothers in 1903. Making further advances in materials and power electronics, and optimising the airframe, could enable the craft to fly faster and for longer. It may also be possible to use solar panels to generate the electricity needed to power the ion drive. One of the big advantages of an ion-powered craft is its near-zero levels of noise. So it's likely the technology will find its first application in silent drones. Its lack of moving parts should make it relatively easy to scale the system down for smaller craft and make it easier to scale up. But bigger craft will also need a bigger increase in power. To build an ion-powered airliner you would need to increased the amount of power relative to the craft's size 300 fold. But look how far we have come since the Wright Brothers' first flight. The sky may be the limit with this new technology. Journal reference: Nature Provided by: The Conversation
  14. Remarkably, the question cannot be answered. Einstein's theory of relativity gives the rate of time in any "inertial frame" relative to that in any other inertial frame. (Inertial frames are traditionally called Lorentz frames, after the person who first introduced the transformation.) According to relativity theory, there is no inertial frame that travels at the speed of light. Therefore, according to our current theory, the question is fundamentally unanswerable. What we can say is this: compared to an Earth-bound clock, the clock in a frame moving at velocity v progresses at a slower rate. In the limit as the frame velocity approaches the speed of light, that rate approaches zero. But that does not mean that the value at c is zero. To do that, mathematically, you must first show that the limiting situation exists. According to relativity theory, it does not. Some future theory might give a different answer, but in the present day, no alternative to relativity theory has made predictions that show it to be correct. - Richard Muller, Prof Physics, UCBerkeley, author of "Now-Physics of Time" (2016)

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