Posted on 08/13/2016 8:51:10 PM PDT by ckilmer
The hunt for exoplanets has been heating up in recent years. Since it began its mission in 2009, over four thousand exoplanet candidates discovered by the Kepler mission, several hundred of which have been confirmed to be “Earth-like” (i.e. terrestrial). And of these, some 216 planets have been shown to be both terrestrial and located within their parent star’s habitable zone (aka. “Goldilocks zone”).
(Excerpt) Read more at universetoday.com ...
I can’t wait for Death’s End. The story itself is sort of written poorly, IMHO but the wealth of new ideas is stunning.
Lol, good one.
On the contrary, Apollo technology from the 60s seems like magic today.
I don’t know, whose to we can’t come up with some “warp” like technology? Doesn’t mean humans can travel that fast but certainly artificial life (robotics) can. They are talking about nanotechnology that might be able to achieve some sort of warp speed so who knows.
Theoretically correct, but not possible practically. No power source even nuclear capable of it. Do the math. 200 days at 1G = 104,727 miles/second or 56% lightspeed. Much faster and you'll start getting into relativistic effects (Making the math a lot harder). 100% efficient conversion would require 1/2 mv2 energy. total conversion of the mass you're accelerating to energy is E=mC2.
If you take the ratio of the squared velocity of your probe to the squared velocity of light times 2 then you require 16% of the mass of the object you're accelerating to be completely converted to energy an that energy to be 100% efficiently converted to momentum. but the 2nd law of thermodynamics applies to ALL processes, so figure about 33% efficiency at best, so 48% of the mass would be required in a process that converts matter 100% to energy - a process that doesn't exist.
Travel to the stars will in a human lifespan remains possible only in science fiction
You know, as my wife and I were reading the first two books it occurred to me, go back and look, the really good books with great ideas that became reality were Jules Verne and HG Wells 100 years ago and the 50 years ago Bradbury, Assimov, etc. we’re American. So there was a shift from British to American and now we have these books which, of course, borrow heavily from precursors but are updated with current/future technology that gives insight to a brilliant mind. That mind is Chinese.
I am happy for the Chinese but sad to see America relinquishing the role of the world’s culture richest in ideas.
Kudos to you if you can delve into the realm of imagination and devolve yourself from the reality of physics on earth.
There are people rethinking the whole Venus is terrible theory, using its challenges as benefits. These links gives some examples:
Figured it was something like that. Couldn’t resist.
4.25 light-years away is a long way. "...unless we make a major breakthrough in the realms of fusion, antimatter, or laser technology, we will either have to be content with exploring our own Solar System, or be forced to accept a very long-term transit strategy…" http://www.universetoday.com/15403/how-long-would-it-take-to-travel-to-the-nearest-star/
Nuclear Thermal and Nuclear Electric Propulsion (NTP/NEP): Another possibility for interstellar space flight is to use spacecraft equipped with nuclear engines, a concept which NASA has been exploring for decades. In a Nuclear Thermal Propulsion (NTP) rocket, uranium or deuterium reactions are used to heat liquid hydrogen inside a reactor, turning it into ionized hydrogen gas (plasma), which is then channeled through a rocket nozzle to generate thrust...
However, despite these advantages in fuel-efficiency and specific impulse, the most sophisticated NTP concept has a maximum specific impulse of 5000 seconds (50 kN·s/kg).
...adjusted for a one-way journey to Proxima Centauri, a nuclear rocket would still take centuries to accelerate to the point where it was flying a fraction of the speed of light. It would then require several decades of travel time, followed by many more centuries of deceleration before reaching it destination. All told, were still talking about 1000 years before it reaches its destination. Good for interplanetary missions, not so good for interstellar ones.
Nuclear Pulse Propulsion: Nuclear pulse propulsion is a theoretically possible form of fast space travel...
But of course, there the inevitable downsides to the design. For one, a ship of this size would be incredibly expensive to build. According to estimates produced by Dyson in 1968, an Orion spacecraft that used hydrogen bombs to generate propulsion would weight 400,000 to 4,000,000 metric tons. And at least three quarters of that weight consists of nuclear bombs, where each warhead weights approximately 1 metric ton.
All told, Dyson’s most conservative estimates placed the total cost of building an Orion craft at 367 billion dollars. Adjusted for inflation, that works out to roughly $2.5 trillion dollars – which accounts for over two thirds of the US government’s current annual revenue. Hence, even at its lightest, the craft would be extremely expensive to manufacture.
There’s also the slight problem of all the radiation it generates, not to mention nuclear waste. In fact, it is for this reason that the Project is believed to have been terminated, owing to the passage of the Partial Test Ban Treaty of 1963 which sought to limit nuclear testing and stop the excessive release of nuclear fallout into the planet’s atmosphere.
Fusion Rockets: Another possibility within the realm of harnessed nuclear power involves rockets that rely on thermonuclear reactions to generate thrust...
But of course, the project also identified numerous stumbling blocks that made it unfeasible using then-current technology – most of which are still unresolved.
For instance, there is the fact that helium-3 is scare on Earth, which means it would have to be mined elsewhere (most likely on the Moon). Second, the reaction that drives the spacecraft requires that the energy released vastly exceed the energy used to trigger the reaction. And while experiments here on Earth have surpassed the “break-even goal”, we are still a long way away from the kinds of energy needed to power an interstellar spaceship.
Third, there is the cost factor of constructing such a ship. Even by the modest standard of Project Daedalus’ unmanned craft, a fully-fueled craft would weight as much as 60,000 Mt. To put that in perspective, the gross weight of NASA’s SLS is just over 30 Mt, and a single launch comes with a price tag of $5 billion (based on estimates made in 2013).
More: http://www.universetoday.com/15403/how-long-would-it-take-to-travel-to-the-nearest-star/
Well said.
That is far far from what would be necessary. The Incredible Design of the Earth and Our Solar System
http://www.islandone.org/Propulsion/ProjectOrion.html
The space vehicles themselves should have cost less, since they were to be built “like battleships” without the expensive materials and engineering components required for the Saturn V and associated capsules.
I think the bigger problem, aside from fallout, would be the need to have several generations of space travelers. You'd have to send people in the early twenties with young kids, and commit them and their children's children to the round trip. Perhaps a better approach would be to send a probe, with the ability to send back data by light transmission:
4.25 light-years away is a long way.
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agree but given the rate of technological acceleration —its not implausible that even 20 years from now — we’ll have very different and more powerful tech to work with.
If judgment and the Lord tarries, but so also would the tech for development on Mars. But far far more is necessary for human life to actually have an alternative to Earth, and we know very little about these "habitable zone" planets. I am interested in investigating Mercuy however, not to live but to know more about the neglected planet.
Not if we ‘jack one of those gray, almond eyed bitchez rides!
Alright - 13,000 light years is still 3000 times further away than Centauri, right?
I either read about this or watched it on an earthly station just recently! It is so exciting! I want to go to the one in Red Dwarf. You never know, we might find a cat.
Thank you for posting this thread! It really is exciting!
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