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Tagged with “stars” (8)

  1. Caravans in Space

    Is the Earth too perfect? The Moon too grey? Mars too dusty? Then how about setting up a human colony in the depths of space?

    Richard Hollingham travels to the Tennessee Valley Interstellar Workshop in Chattanooga, Tennessee to meet scientists, engineers, doctors and anthropologists planning human colonies in space and spaceships that will take humanity to the stars.

    These are not dreamers - although they all have an ambitious dream - but well qualified experts. Several work at Nasa, others have day jobs at universities and research institutes.

    Richard hears of proposals to build giant space stations and worldships - vessels packed with the best of humanity. These caravans in space might be lifeboats to escape an approaching asteroid or perhaps the first step to colonising the galaxy.

    —Huffduffed by adactio

  2. How to fly to Alpha Centauri

    Talking about building an interstellar space ship makes you sound like a sci-fi fan who’s lost touch with the real world. Unless you’re Mae Jemison, a former astronaut — the first African-American woman in space. Then you might legitimately wonder, “How in the hell do you get to another star system?”

    Jemison actually needs to answer that question; she’s the head of 100 Year Starship, an organization the home page of which boldly commands, “Let’s make human interstellar travel capabilities a reality within the next hundred years.”

    “That time frame is reasonable, why?” she asks rhetorically. “If you said ten years — ‘Nah, we know that’s not long enough.’ If you said 500 years, people would say, ‘I can kick back for another two to three hundred years because I don’t have to worry about it.’ One hundred years is close enough."

    The problem: space is big, and our current rocket technology isn’t cutting it. “If you’re travelling with technology we can already conceive, like say the Voyager spacecraft, it’s going to take about 80,000 years to travel a distance to our nearest neighboring star," says Marc Millis, the head of the Tau Zero Foundation. “And it is going 0.00006 times the speed of light.” Nuclear-powered spacecraft might go much faster, and have their proponents, but are politically and environmentally dangerous: no one wants to risk a nuclear meltdown during liftoff.

    The heads of yet another interstellar organization, Starship Century, think they are on the right track. James Benford is president of a company that does microwave research; his identical twin brother Gregory is an astrophysicist at the University of California, Irvine. The Benfords make a strong case for a technology right out of a science fiction novel. The technology is the beam sail, and the book is Rocheworld, written by Robert Forward in 1982. “[It’s] a very solid scientific concept for a starship,” James says.

    A beam sail is like a regular sail — “envision it as a giant umbrella, maybe 100 meters across,” says Gregory — pushed with microwave beams, instead of wind, to extremely high speeds. Beam sails are still in the experimental phase, and far more tests will be necessary on Earth and in space before we know if they can propel an object across the galaxy. Even Jemison admits that the hundred-year estimate is kind of a tease — it’s more about figuring out the physics than building the Enterprise.

    But Gregory Benford likes to remind us of how greatly we underestimate the pace of change. “Thomas Jefferson said in 1812 that it will take 1,000 years for the republic to reach the Pacific. He never envisioned that 57 years later, a train would run all the way to San Francisco.”

    —Huffduffed by adactio

  3. Will sci-fi save us?

    What does today’s sci-fi mean for our real-life future? Cyberpunk author Neal Stephenson argues that it’s time to get over our love of dystopia. A class at MIT searches sci-fi classics for technologies they can invent right now, although maybe they shouldn’t. Geoengineers take a tip from Carl Sagan – who saw a green future for Mars – to see if we can save Earth. And we meet some scientists who think that if we ever want to see the stars, we’d better start building the starship.

    —Huffduffed by adactio

  4. Astronomycast 145: Interstellar Travel

    In science fiction it’s easy to hop into your spaceship and blast off for other stars. But the true distances between stars, and the limits of relativity make interstellar travel almost impossible with our current technology. What would it really take to travel from star to star, exploring the galaxy?

    —Huffduffed by adactio

  5. Peter Schwartz: The Starships ARE Coming - The Long Now

    We now know, Schwartz began, that nearly all of the billions of stars in our galaxy have planets. If we can master interstellar travel, "there’s someplace to go." Our own solar system is pretty boring—-one planet is habitable, the rest are "like Antarctica without ice" or worse.

    So this last year a number of researchers and visionaries have begun formal investigation into the practicalities of getting beyond our own solar system. It is an extremely hard problem, for two primary reasons—-the enormous energy required to drive far and fast, and the vast amount of time it takes to get anywhere even at high speed.

    The energy required can be thought of in three ways. 1) Impossible—-what most scientists think. 2) Slow. 3) Faster than light (FTL). Chemical rockets won’t do at all. Nuclear fission rockets may suffice for visiting local planets, but it would take at least fusion to get to the planets of other stars. Schwartz showed Adam Crowl’s scheme for a Bussard Ramjet using interstellar ions for a fusion drive. James Benford (co-author of the book on all this, Starship Century) makes the case for sail ships powered by lasers based in our Solar System.

    As for faster-than-light, that requires "reinventing physics." Physics does keep doing that (as with the recent discovery of "dark energy"). NASA has one researcher, Harold White, investigating the potential of microscopic wormholes for superluminal travel.

    Standard-physics travel will require extremely long voyages, much longer than a human lifetime. Schwartz suggested four options. 1) Generational ships—-whole mini-societies commit to voyages that only their descendents will complete. 2) Sleep ships—-like in the movie "Avatar," travelers go into hibernation. 3) Relativistic ships—-at near the speed of light, time compresses, so that travelers may experience only 10 years while 100 years pass back on Earth. 4) Download ships—-"Suppose we learn how to copy human consciousness into some machine-like device. Such ‘iPersons’ would be able to control an avatar that could function in environments inhospitable to biological humans. They would not be limited to Earthlike planets."

    Freeman Dyson has added an important idea, that interstellar space may be full of objects—-comets and planets and other things unattached to stars. They could be used for fuel, water, even food. "Some of the objects may be alive." Dyson notes that, thanks to island-hopping, Polynesians explored the Pacific long before Europeans crossed the Atlantic. We might get to the stars by steps.

    Futurist Schwartz laid out four scenarios of the potential for star travel in the next 300 years, building on three population scenarios. By 2300 there could be 36 billion people, if religious faith drives large families. Or, vast wealth might make small families and long life so much the norm that there are only 2.3 billion people on Earth. One harsh scenario has 9 billion people using up the Earth.

    Thus his four starship scenarios… 1) "Stuck in the Mud"—-we can’t or won’t muster the ability to travel far. 2) "God’s Galaxy"—-the faithful deploy their discipline to mount interstellar missions to carry the Word to the stars; they could handle generational ships. 3) "Escape from a Dying Planet"—-to get lots of people to new worlds and new hope would probably require sleep ships. 4) "Trillionaires in Space"—-the future likes of Elon Musk, Jeff Bezos, and Richard Branson will have the means and desire to push the envelope all the way, employing relativistic and download ships or even faster-than-light travel.

    Schwartz concluded that there are apparently many paths that can get us to the stars. In other words, "Galactic civilization is almost inevitable."

    —Huffduffed by adactio

  6. The 100 Year Starship

    Dr. Mae Jemison was the first black woman in space. Now, she’s leading a wildly ambitious project: to achieve interstellar travel in the next 100 years. She’s with us.

    Think Star Trek and you won’t be far off. A new Pentagon project is putting out seed money for interstellar travel. Humans, rambling around among the stars. It’s called the 100 Year Starship project. It’s as wildly ambitious as just about anything you can imagine.

    The spaceship, its energy source, its passengers’ survival – full-blown or just as DNA… all giant challenges. Not to mention that we’re sort of broke and not even flying space shuttles right now. Leader of the new effort: astronaut Mae Jemison, the first black woman in space. She’s with us.

    This hour, On Point: the 100 Year Starship.

    —Huffduffed by adactio

  7. Lord Martin Rees: Life and the Cosmos

    It’s famously called the Final Frontier, and thanks to rapidly developing technology we now know more about the outer reaches of our galaxy than ever. But that leaves unknowns.

    Does the universe have any limits? Are there any other earth-like planets out there? And the big one, are we alone?

    Addressing the University of Melbourne recently, Britain’s Astronomer Royal, Lord Martin Rees, reports on the latest research.

    —Huffduffed by adactio