[Home] [Headlines] [Latest Articles] [Latest Comments] [Post] [Sign-in] [Mail] [Setup] [Help]
Status: Not Logged In; Sign In
|
Science/Tech See other Science/Tech Articles Title: The Search for Eath 2.0: Will We Make It Out Alive? Someday, this world's gonna end. So we have to get off it. The good news is that we have some time to solve a couple major problems: finding another habitable planet and developing the technology to get us there. Although we did manage to make it through the Cold War without a nuclear holocaust, we keep inventing new possibilities for self-destruction. So there's that to consider. But it's a fact: Our sun, like all stars, will eventually burn out. Setting aside the ever-present (and, right now, waxing) possibility that we do ourselves in, about 5 billion years from now, the sun will expand and engulf the inner planets of the solar system. Eventually, Earth will be vaporized. But we don't have to be around to suffer the experience. That's the hope driving the search for Earth 2.0. And that hope was renewed last week with the announcement that a team of researchers using European Southern Observatory telescopes and other facilities "have found clear evidence of a planet orbiting the closest star to Earth, Proxima Centauri." That's not all: This "exoplanet" may look a lot like Earth. What we're calling Proxima b orbits its red dwarf star every 11 Earth days. And its temperature makes it "suitable for liquid water to exist on its surface," according to ESO. A "rocky world," it's a little bigger than Earth. A paper detailing the discovery was published by the journal Nature on Aug. 25, 2016. Eventually, Earth will be vaporized. The good news is we won't be around to suffer the experience. According to Dr. Caleb Scharf, director of astrobiology at Columbia University and a world-renowned research astrophysicist, "It means that at a cosmically trifling 24 trillion miles (4.243 light years) from where you are at this instant is an alien system with a planet that could conceivably harbor life as we know it." "Cosmically trifling" is still a long distance, nearly 300,000 times the distance from the Earth to the sun. Finding Earth 2.0 is one thing. Actually getting there is another. It's a question of how we power a spacecraft that will allow us to make such a journey, which boils down to fuel, weight and time. Even the strongest conventional rockets won't work. It would take 78,000 years to travel to Proxima Centauri using technology used to power the New Horizons spacecraft that reached Pluto 9½ years after it launched. The unmanned Voyager 1 and Voyager 2 probes are about to leave our solar system. If they'd been headed for Proxima Centauri, it would have taken tens of thousands of years. "And at a maximum speed of about 17,600 miles per hour, it would have taken a space shuttle about 165,000 years," adds EarthSky's Deborah Byrd. NASA has explored the limits of existing technology, most notably with Project Longshot, "a conceptual interstellar spacecraft design." "It would have been an unmanned probe, intended to fly to and enter orbit around Alpha Centauri B," in the cosmic neighborhood of Proxima Centauri and Proxima b, "powered by nuclear pulse propulsion," Wikipedia tells us. "Developed by the U.S. Naval Academy and NASA, from 1987–88, Longshot project researchers had "existing technology in mind, although some development would have been required." Indeed, Longshot assumed "a three-order-of-magnitude leap over current propulsion technology," said Real Clear Science. The researchers focused on nuclear pulse propulsion, a concept suggested in 1947 by Stanislaw Ulam and explored via Project Orion in the 1950s and 1960s and Project Daedalus in the 1970s. Finding Earth 2.0 is one thing. Actually getting there is another. The primary enabling technology for the Longshot rocket would be "a pulsed fusion microexplosion drive with 1 million seconds of specific impulse. "A large, long-life nuclear fission reactor with 300 kilowatts of power output" would support the running of the probe's systems, say the original specifications. According to Wikipedia, "the journey to Alpha Centauri B orbit would take about 100 years, at an average velocity of approximately 13,411 kilometers per second, or about 4.5% the speed of light." A manned mission would, obviously, have to go faster than that — approaching the speed of light. And it's not possible…right now. But research into a concept known as the Alcubierre warp drive is already underway. This particular brand of Star Trek tech is named for theoretical physicist Miguel Alcubierre, who, in a paper published in 1994, described a solution to Einstein's equations of general relativity. Alcubierre says the warp drive is essentially "a modification of space time in a way that allows a space ship to travel at an arbitrarily large speed." According to NASA, this is simply a "credible concept" right now. It's too soon to know if it's viable. Other theoretical approaches to deep space travel include aerospace engineer Roger Shawyer's EmDrive, which was once described as snake oil but is now generating buzz because other researchers have been able to reproduce Shawyer's results. The EmDrive is basically a truncated cone. Bouncing microwaves back and forth inside the cone create thrust toward the narrow end of it, converting one type of energy into kinetic energy. Critics questioned how Shawyer's system increased momentum as it began to move in violation of the law of conservation of momentum. But in 2012, Chinese researchers measured thrust created by its own version of the EmDrive. And in 2015, NASA confirmed that the EmDrive does indeed create thrust. So far, six independent experiments have confirmed the viability of the EmDrive. A manned mission would obviously have to go faster than that — approaching the speed of light. And it's not possible…right now. For its part, the U.S. space agency is exploring ways to advance ion propulsion for missions to deep space and beyond. Several years ago, NASA tells us its "Evolutionary Xenon Thruster (NEXT) project… completed a test that powered the ion engine for over 48,000 hours, That's 5½ years of thruster operation, the longest-duration test of any space propulsion system in history. "NEXT consumed 860 kg of xenon propellant. A conventional rocket would require 10,000 kg of propellant to provide the same amount of total momentum." NEXT is a solar electric propulsion (SEP) engine. "SEP uses electricity generated by solar panels, to power an electric thruster." The primary breakthrough is that "because it reduces the amount of propellant needed for a given mission, it greatly reduces the weight of the vehicle." In addition to NASA's work, there are private efforts to solve the power/fuel/weight/time problem. In April 2016, Russian billionaire Yuri Milner announced a $100 million investment in proof-of-concept studies for new ways to reach the stars as part of his Breakthrough Initiatives. Breakthrough Starshot has significant intellectual and entrepreneurial heft behind it, including big names like Stephen Hawking and Mark Zuckerberg. The $100 million will fund research into the use of a 100-gigawatt light beam and light sails "to propel approximately 1,000 ultra-lightweight nanocraft to 20% of light speed," according to EarthSky. Immortality from the species' perspective is all about theoretical physics and aerospace technology. We're actually getting there, too. If possible, such a mission "could reach Alpha Centauri within about 20 years of launch." The Planetary Society is currently testing the use of light sails, with a privately funded project called, appropriately enough, LightSail. The first LightSail test, in 2015, didn't fly high enough to escape Earth's atmospheric drag and do some solar sailing — but the deployment system was successful. A second test — during which a SpaceX heavy-lift rocket will carry LightSail 2 into orbit, high enough to be free from atmospheric drag — is set for later this year. The organization's site tells us, "LightSail's primary contractor is Ecliptic Enterprises Corp…. Boreal Space and Aquila Space serve as contractors to Ecliptic. LightSail was built by Stellar Exploration Inc." Immortality from an individual perspective is a matter of emerging science and biotechnology. And we're actually getting there. Immortality from the species' perspective is all about theoretical physics and aerospace technology. We're actually getting there, too. This part of the 21st century space race — one we all win — is well underway. Poster Comment: In the Year 2525... Post Comment Private Reply Ignore Thread Top • Page Up • Full Thread • Page Down • Bottom/Latest
#1. To: BTP Holdings (#0)
Should We? :-) _____________________________________________________________ USA! USA! USA! Bringing you democracy, or else! there were strains of VD that were incurable, and they were first found in the Philippines and then transmitted to the Korean working girls via US military. The 'incurables' we were told were first taken back to a military hospital in the Philippines to quietly die. – 4um
|
||
|
[Home]
[Headlines]
[Latest Articles]
[Latest Comments]
[Post]
[Sign-in]
[Mail]
[Setup]
[Help]
|
||