≡ Menu

The Alpha Centauri Angle

Apropos of yesterday’s article on the discovery of Proxima Centauri, it’s worth noting that Murray Leinster’s story “Proxima Centauri,” which ran in Astounding Stories in March of 1935, was published just seven years after H. A. Alden’s parallax findings demonstrated beyond all doubt that Proxima was the closest star to the Sun, vindicating both Robert Innes and J. G. E. G. Voûte. Leinster’s mile-wide starship makes the first interstellar crossing only to encounter a race of intelligent plants, the first science fiction story I know of to tackle the voyage to this star.

proxima_astounding

The work surrounding Proxima Centauri was intensive, but another fast-moving star called Gamma Draconis in Draco, now known to be about 154 light years from Earth thanks to the precision measurements of the Hipparcos astrometry satellite, might have superseded it. About 70 percent more massive than the Sun, Gamma Draconis has an optical companion that may be an M-dwarf at about 1000 AU from the parent. Its bid for history came from the work of an astronomer named James Bradley, who tried without success to measure its parallax. Bradley was working in the early 18th Century on the problem and found no apparent motion.

Stellar parallax turned out to be too small an effect for Bradley’s instruments to measure. Most Centauri Dreams readers will be familiar with the notion of observing the same object from first one, then the other side of the Earth’s orbit, looking to determine from the angles thus presented the distance to the object. It’s no wonder that such measurements were beyond the efforts of early astronomers and the apparent lack of parallax served as an argument against heliocentrism. A lack of parallax implied a far greater distance to the stars than was then thought possible, and what seemed to be an unreasonable void between the planets and the stars.

It would fall to the German astronomer Friedrich Wilhelm Bessel to make the first successful measurement of stellar parallax, using a device called a heliometer, which was originally designed to measure the variation of the Sun’s diameter at different times of the year. As so often happens in these matters, Bessel was working on 61 Cygni at the same time that another astronomer — his friend Thomas Henderson — was trying to come up with a parallax reading for Alpha Centauri. Henderson had been tipped off by an observer on St. Helena who was charting star positions for the British East India Company that Alpha Centauri had a large proper motion.

Henderson was at that time observing at the Cape of Good Hope, using what turned out to be slightly defective equipment that may have contributed to his delays in getting the Alpha Centauri parallax into circulation. In any event, Bessel’s heliometer method proved superior to Henderson’s mural circle and Dollond transit (see this Astronomical Society of Southern Africa page for more on these instruments), and Bessel’s findings on 61 Cygni were accepted by the Royal Astronomical Society in London in 1842, while Henderson’s own figures were questioned.

Friedrich_Wilhelm_Bessel_(1839_painting)

Bessel thus goes down as the first to demonstrate stellar parallax. Henderson went on to tighten up his own readings on Alpha Centauri, using measurements taken by his successor at the Royal Observatory at the Cape of Good Hope, but it took several decades for the modern value of the parallax to be established. But both astronomers were on to the essential fact that parallax was coming within the capabilities of the instruments of their time, and by the end of the 19th Century, about 60 stellar parallaxes had been obtained. The parallax of Proxima Centauri, for the record, is now known to be 0.7687 ± 0.0003 arcsec, the largest of any star yet found.

Image: A portrait of the German mathematician Friedrich Wilhelm Bessel by the Danish portrait painter Christian Albrecht Jensen. Credit: Wikimedia Commons.

While the Hipparcos satellite was able to extend the parallax method dramatically, it falls to the upcoming Gaia mission to measure parallax angles down to an accuracy of 10 microarcseconds, meaning we should be able to firm up distances to stars tens of thousands of light years from the Earth. Indeed, working with stars down to magnitude 20 (400,000 times fainter than can be seen with the naked eye), Gaia will be able to measure the distance of stars as far away as the galactic center to an accuracy of 20 percent. The Gaia mission’s planners aim to develop a catalog encompassing fully one billion stars, producing a three-dimensional star map that will not only contain newly discovered extrasolar planets but brown dwarfs and thousands of other objects useful in understanding the evolution of the Milky Way.

One can only imagine what the earliest reckoners of stellar distance would have made of all this. Archimedes followed the heliocentric astronomer Aristarchus in calculating that the distance to the stars, compared to the Sun, was proportionally as far away as the ratio of the radius of the Earth was to the distance to the Sun (thanks to Adam Crowl for this reference). Using the figures he was working with, that works out to a stellar distance of 100 million Earth radii, a figure then all but inconceivable. If we translated into our modern values for these parameters, the stars Aristarchus was charting would be 6.378 x 1011 (637,800,000,000) kilometers away. The actual distance to Alpha Centauri is now known to be roughly 40 trillion (4 x 1013) kilometers.

tzf_img_post

Comments on this entry are closed.

  • GaryChurch April 25, 2013, 8:27

    http://www.gutenberg.org/wiki/Science_Fiction_%28Bookshelf%29

    Some Astounding stories; some still read well, many do not. If you go through a dozen or so you will quickly realize this is where screenwriters and directors have pirated all their “original” works.

  • ljk April 25, 2013, 13:05

    Another relevant Leinster story is “First Contact”, of which you can find three different radio play versions of it here, along with some other stories that appear to be variations on similar themes:

    http://www.sffaudio.com/?page_id=4072

    Just think, Aristarchus of Samos had the mostly right version of the Sol system setup and the stars over two thousand years ago. One does have to wonder how our knowledge might have improved sooner if we had gone with his ideas, rather than stick with the geocentric version of existence.

    Would we have sent vessels to the stars centuries earlier as Sagan suggested in Cosmos? At the least we would have accepted the idea of other solar systems and the connecting logic of worlds with life much sooner, with its own important implications.

  • Thomas Mazanec April 25, 2013, 13:14

    What I don’t understand is why not some c1800 astronomer assumed all stars to be alike. He would think Sirius was the closest star, and would have gotten a distance almost close enough to measure a parallex. If he figured stars were like most anything in nature and were of varying brightness, and that Sirius was unusually bright as well as unusually close, he could have gotten a good reason for not detecting the parallex, however.

  • Robert Feyerharm April 25, 2013, 14:03

    Is it feasible astronomers will eventually catalogue *all* of the stars in our Galaxy? If Gaia will measure up to 1 billion, how soon before all 200-400 billion stars in the Milky Way (going by Wikipedia) have been observed, in visual light or IR to peer through the dust?

  • FrankH April 25, 2013, 15:57

    The error in the modern distance to Proxima Centauri is about 105AU… that’s the width of the Kuiper belt, at least out to the “Kuiper cliff”. I don’t know if I should be impressed at the parallax accuracy or depressed by the same.

  • Peter Chapin April 25, 2013, 16:49

    I’m really excited about the Gaia mission. What a treasure trove of information it will provide! It’s great to be living in a time when such missions can be launched and when the information gathered by them can be made readily available to all thanks to the miracle of the Internet.

  • GaryChurch April 25, 2013, 17:35

    “One does have to wonder how our knowledge might have improved sooner if we had gone with his ideas, rather than stick with the geocentric version of existence.”

    Two steps forward, one step back.
    Charles Pellegrino authored “Return to Sodom and Gomorah”- a fascinating work about ancient history and what could have been if Santorini had not exploded.
    Unfortunately he has been stripped of his creds and his recent work revealed to be innaccurate.
    http://en.wikipedia.org/wiki/Charles_Pellegrino

    Which does not change my opinion of his book. An excellent read.

  • coolstar April 25, 2013, 20:29

    Nicely done Paul and I’m always happy to reclaim Bessel from the maths folks. I think you neglected to mention that Bessel’s first parallax was from 61 Cygni though, and his value was 0.314 arc-seconds, less than half that of Alpha Cen.
    The current best value is 0.286. The system is actually a visual binary of 61 Cyg A & B and contains two similar K dwarfs (K5 & K7). And I don’t know which star Bessel measured or if it was both. 61 Cgy A is about 0.8 magnitudes brighter. Both stars are spotted and belong to the BY Dra class of variable stars.

  • Paul Gilster April 26, 2013, 8:40

    Right you are, coolstar! I did entirely leave out 61 Cygni, an oversight I’ve just now corrected in the text. Thanks for noting the slip.

  • ljk April 26, 2013, 9:29

    Pellegrino’s SF novel The Killing Star brings up some very interesting and rather frightening possibilities regarding our emergence into the galaxy and what might happen when we gain the notice of advanced ETI:

    http://www.projectrho.com/public_html/rocket/aliens.php#id–The_Fermi_Paradox–The_Killing_Star

    The novel also discusses his design for an antimatter-powered starship, which was the basis for the ISV Venture Star in the 2009 film Avatar:

    http://www.projectrho.com/public_html/rocket/realdesigns.php#id–Avatar_ISV_Venture_Star

  • GaryChurch April 28, 2013, 9:09

    “-his design for an antimatter-powered starship-”

    Anti-matter may be just a little too difficult to contain safely- and it is not clear if it can ever be produced in quantity. However his Valkrie concept is far ahead of any other real world design- there is no arguing that.

    But IMO, the pure anti-matter rocket is not going to be used though it may be part of a pulse propulsion system. While igniting fusion bombs with a little anti-matter may work well in the near future for a “slow boat”, the most probable candidate for a definitive future star drive is the small black hole engine sometime in the next century.

  • Eniac April 28, 2013, 23:13

    Black holes as a propulsion system are even much more remote than antimatter. There is absolutely no realistic path known to obtain one. Small ones don’t last long enough for a trip, and you can’t feed them because of their minuscule cross-section. Larger ones are too heavy to go anywhere on the energy they produce. Might as well have an FTL drive….

  • GaryChurch April 29, 2013, 9:43

    “There is absolutely no realistic path known to obtain one.”

    Uh-huh. Not according to the guy who wrote the paper.

    As for an FTL drive, that is impossible- black holes are real.

    http://www.phys.ksu.edu/news/2012/westmoreland.html

  • Eniac April 30, 2013, 1:28

    There is absolutely no realistic path known to obtain one.

    Uh-huh. Not according to the guy who wrote the paper.

    Right, indeed not. Or would you like to point out where in the paper there is described a realistic way to obtain a black hole? I did not think so…

    From the paper:

    “A black hole with a mass of 1.8 million tons would last about 100 years and would output about 17 million billion watts of power,” Shawn said. “That’s about 1000 times the amount of power that the entire world currently consumes on average. What’s really mind boggling is that this incredible power source is 300 times smaller than a proton!”

    17 million billion watts sounds like a lot, but it is only good for 60 million Newtons of thrust. Apply this to 1.8 million tons, and you get an acceleration of 0.003 g. Not stellar, really.

    The way around this, of course, would be a smaller hole that is being fed. I have some very serious doubts about that, though. As they say in the paper, even the 1.8 Mt hole is 300 times smaller than a proton. It would be very hard to cram enough matter down such a tiny throat to make any difference in the mass loss. And you’d be going against a strong headwind of Hawking radiation coming the other way.

    In summary: There is absolutely no realistic path known to obtain a black hole. Small ones don’t last long enough for a trip, and you can’t feed them because of their minuscule cross-section. Larger ones are too heavy to go anywhere on the energy they produce.

  • GaryChurch April 30, 2013, 10:50

    “-would you like to point out where in the paper there is described a realistic way to obtain a black hole? I did not think so…”

    http://arxiv.org/pdf/0908.1803.pdf

    IV. Theoretical Feasibility
    In this section we want to discuss whether the Physics of black holes discussed
    above, together with the laws of Physics of matter as we know them, make it
    possible to produce artificial BHs which would be useful, either as power plants
    or as starships.
    7
    Since the mass of a black hole decreases with its radius, while its energy
    output increases and its life expectancy decreases, this is a delicate question.
    List of criteria: We need a black hole which
    1. has a long enough lifespan to be useful,
    2. is powerful enough to accelerate itself up to a reasonable fraction of the speed
    of light in a reasonable amount of time,
    3. is small enough that we can access the energy to make it,
    4. is large enough that we can focus the energy to make it,
    5. has mass comparable to a starship.
    We could easily imagine that this would be impossible. Somewhat surprisingly,
    it turns out that there is a range of BH radii, which according to the
    semiclassical approximation, fit these criteria.
    Using the formulae from the section above, we find that a black hole with
    a radius of a few attometers at least roughly meets the list of criteria (see
    Appendix). Such BHs would have mass of the order of 1,000,000 tonnes, and
    lifetimes ranging from decades to centuries. A high-efficiency square solar panel
    a few hundred km on each side, in a circular orbit about the sun at a distance of
    1,000,000 km, would absorb enough energy in a year to produce one such BH.
    A BH with a life span on the order of a century would emit enough energy
    to accelerate itself to relativistic velocity in a period of decades. If we could let
    it get smaller and hotter before feeding matter into it, we could get a better
    performance.
    In Section V below, we discuss the plausibility of creating SBHs with a
    very large spherically converging gamma ray laser. A radius of 1 attometer
    corresponds to the wavelength of a gamma ray with an energy of about 1.24
    TeV. Since the wavelength of the Hawking radiation is 82 times the radius of
    the BH, the Hawking temperature of a BH with this radius is on the order of
    16 GeV, within the limit of what we could hope to achieve technologically.
    Now the idea that the wavelength of the radiation should match the radius
    of the BH created is very likely pessimistic. The collapsing sphere of radiation
    would gain energy from its self-gravitation as it converged, and there is likely
    to be a gravitational self-focussing.
    This is a problem that can be studied using standard techniques from classical
    general relativity in which Einstein’s equation is coupled to Maxwell’s
    equations in vacuum, or “electrovac.” We intend to investigate this in the future.
    Thus it seems that making an artificial black hole and using it to drive a
    starship is just possible, because the family of BH solutions has a “sweet spot.”

  • andy April 30, 2013, 19:32

    The error in the modern distance to Proxima Centauri is about 105AU… that’s the width of the Kuiper belt, at least out to the “Kuiper cliff”. I don’t know if I should be impressed at the parallax accuracy or depressed by the same.

    My preference is to characterise it in terms of how well we know the multiplicity of the system. We still don’t know for certain if Proxima is actually gravitationally bound to Alpha Centauri.

  • ljk May 1, 2013, 9:52

    Forget making a black hole, what government or business is going to authorize the funds for a “high-efficiency square solar panel a few hundred km on each side, in a circular orbit about the sun at a distance of
    1,000,000 km” ?

    Tell your typical congressman or person on the street that it is for making a black hole and you can say adios to that plan.

    I do not want to be in the group that declares “Man will never fly”, but there has to be some level of reality here. Otherwise we can just have another fifty years of starship symposiums with white papers and fancy slide presentations but no actual star probe let alone a Worldship.

  • GaryChurch May 1, 2013, 19:18

    “I do not want to be in the group that declares “Man will never fly”, but there has to be some level of reality here.”

    The small black hole engine IS the reality- until someone comes up with unobtanium or finds a stargate. Or definitively proves it will not work. Everything else requires exotic matter that so far does not exist except in the imagination. Black holes exist. Solar energy exists. The math is based on things that are real. There is nothing else except bombs, beams, and freezing people for the forseeable future- and we have yet to “authorize the funds for” any research on how to freeze people. So, whether you want to be or not, your comment shows you are effectively in the never fly group.

    Reality.

  • Eniac May 1, 2013, 23:15

    Gary Church: If you consider this wild speculation about theoretical possibilities ending in “We intend to investigate this in the future” to be “a realistic way” you are deluded. There is not even a realistic way to make any gamma ray laser at all. Most physicists would call that impossible. Much less one capable of the mindboggling energy density necessary to even just theoretically allow the formation of a black hole. And as we all know, showing that there is a theoretical possibility is very far from showing that it can actually be done. Time travel and wormholes, for example, fall into this category. The unobtainium you keep talking about is, also, much more realistic than the creation of a black hole using gamma lasers. Antimatter and controlled fusion are child’s play, in comparison.

  • GaryChurch May 2, 2013, 7:53

    Would you like to point out in some paper you have had published and peer reviewed that there is absolutely no way to build a gamma ray laser? I did not think so…

    Why don’t you try a little cup half full commenting for a change?

    http://www.sciencedaily.com/releases/2007/09/070912154633.htm

    http://www.sciencedaily.com/releases/2010/05/100501013620.htm

    http://phys.org/news/2011-05-gamma-ray-laser-emit-nuclear.html

    http://www.laserfocusworld.com/articles/2011/06/laser-physics-nuclear-laser-idea-hints-at-gamma-ray-laser-future.html

  • Eniac May 2, 2013, 20:52

    GaryChurch: Unfortunately, scientists rarely bother to publish on things they consider impossible. On the other hand, it is always easy to come up with flights of fancy in the popular science press on every conceivable subject, including warp drives, wormholes, antigravity, free energy, the works. One person’s half full cup is another’s fantasy ….

  • GaryChurch May 3, 2013, 2:35

    “-as we all know, showing that there is a theoretical possibility is very far from showing that it can actually be done.”

    “-scientists rarely bother to publish on things they consider impossible.”

    Good points, but what point are you trying to make besides just saying NO?

    My point is this; we started with muscle energy, then molecular energy in all it’s variations beginning with camp fires and ending with rocket engines. We moved on to fission of heavy elements and then to effect fusion of light elements we combined molecular energy in the form of explosives to intensify a fission process to make those light elements fuse. That is as far as we have come. It is theoretically possible to have a fusion reactor but I am very skeptical on this next step. My new talking point is that while a star or a bomb deliver fusion energy as advertised, making a star burn in a little box is not like lighting off a bomb at all. Though people with little or no basic knowledge of science may not get my point I am sure you do.

    After fusion the next more powerful force is gravity- and a black hole is the form we can theoretically harness for propulsion. Whether this is possible or not is much like my skepticism concerning fusion reactors. But I am no critic of fusion bombs for propulsion- while most people cannot wrap their heads around that concept.

    In any case a small black hole engine is- or is not- in the future. We can neither confirm (as I may seem to be trying to do) nor deny (as your “absolutlely no way” statement seems to indicate) which way it will go. I am merely pointing out there is nothing else to even speculate about because the other solutions, unlike solar energy manufacured black holes, require an imaginary exotic ingredient.

    The present, IMO, is all about space travel as a medical problem, not an engineering problem. Freezing people is the most important topic for discussion. Yes, the beam is my dream, and it might send a slow boat loaded with frozen people on it’s way and hydrogen bombs might slow them down upon arrival centuries later. That is a scenario that depends on solving far less challengin problems than manufacturing black holes.

    Are we making any progress understanding each other yet?

  • Eniac May 3, 2013, 21:34

    If you look over my comments again, you will find that “absolutely no way” is not how I put it. The strongest words I used were “Most physicists would call it impossible”, and I stand by that.

    The difference between controlled fusion and making a black hole is that the former requires no imaginary exotic ingredient, like a gamma ray laser. Making a black hole is right up there with “harnessing the energy of the vacuum”, “antigravity”, and all the other such nonsense. If you look back over the bistory of this blog, you will find that I have myself speculated about black hole propulsion. As you say, at least black holes do exist. However, you have to keep your perspective, and at this point in time there is absolutely no realistic proposal on how one could be obtained.

  • GaryChurch May 5, 2013, 8:02

    “If you look over my comments again, you will find that “absolutely no way” is not how I put it. The strongest words I used were “Most physicists would call it impossible”, and I stand by that.”

    You wrote, “In summary: There is absolutely no realistic path known to obtain a black hole.”

    “Making a black hole is right up there with “harnessing the energy of the vacuum”, “antigravity”, and all the other such nonsense.”

    Whatever you say. Good luck with that fusion reactor.

  • Ron S May 5, 2013, 14:18

    I had every intention of entirely staying out of this discussion. Now that you’ve reached what appears to be a stalemate I think it may be worth making an observation.

    The fundamental challenge for both controlled fusion and micro-BH creation are not different. They are one and the same thing. In fact it is the very same challenge that faced the developers of both the fission and fusion bomb.

    Have you now realized what that is? In a word: confinement. All these things require confining sufficient energy within a volume to meet the energy density requirement for the target reaction.

    In the case of nuclear bombs the mechanisms were (and still are, I believe) a state secret of both the US and USSR/Russia. The subject is still not often openly discussed .

    To consider a what-if, imagine that the NIF (in the US), had a gamma ray laser of even very modest capability. I imagine they’d find a use for it.

    The energy density (confinement) required to create a micro-BH is orders of magnitude higher, among other fundamental problems. (A spectacularly, jaw-dropping, insane) “if” such a device as envisioned by Westmoreland existed it would long before, in its developmental stages, have been routinely used to fuse fuel pellets.

  • GaryChurch May 5, 2013, 20:20

    “In the case of nuclear bombs the mechanisms were (and still are, I believe) a state secret of both the US and USSR/Russia.”

    In Return to Sodom and Gomorrah, Pellegrino discusses the fact that if you have a chunk of plutonium in each hand and slam them together you will find out there is no secret to nuclear weapons. The secret is just a matter of efficiency. Shooting a piece down a cannon barrel at another raises the efficiency “orders of magnitude.”

    As for using black holes to fuse deuterium- that would be like using a hydrogen bomb to light a barbecue. Why would you do that?

    You would use it to reach a high percentage of C and so far it is the only possibile way to do it.

    Good luck confining that fusion reaction; a black hole is the opposite of confinement by the way.

  • Eniac May 5, 2013, 20:27

    @Ron, you are right, of course. The term “orders of magnitude” does not begin to address the magnitude of the problem, though. You need to focus an enormous amount of power onto a volume a few attometers across. For fusion, it is sufficient to get a much smaller amount of power onto a volume of a millimeter or so across. milli/atto is 10^12, to the third power (for density) is 10^36. Thus, as a very generous rough estimate, we are talking 30-40 orders of magnitude difference here, between fusion and black hole. Spectacular, jaw-dropping, and insane, indeed.

    That should give pause to anyone calling Westmoreland’s ideas “realistic”. They are great ideas, but they are better filed under “wild fantasy” than “realistic approach”, and I am pretty sure that Westmoreland himself would agree with this.

  • Eniac May 5, 2013, 20:39

    @Gary: I consider “not realistic” and “up there with nonsense” weaker than “impossible”, even when the latter is (slightly) moderated by “most physicists consider it”.

    Anyway, I stand by all of them.

    Remember, in order to get something done, you ALWAYS have to say NO to a lot of other options. Making this choice is, in fact, most of the battle. Making a black whole goes squarely in the NO category if “realistic” is supposed to play any part in the equation.

  • Ron S May 6, 2013, 10:50

    Gary, your complete misreading and misunderstanding of everything I said is simply astonishing.

  • GaryChurch May 6, 2013, 19:49

    “All these things require confining sufficient energy within a volume to meet the energy density requirement for the target reaction.”

    It is simply astonishing that you equate fissioning heavy elements with creating a small black hole. No two phenomenon could be more different.

    A nuclear weapon is the use of chemical explosives to create fast fission by concentrating, not confining. That fast fission is used to momentarily create the conditions that exist inside a star.

  • GaryChurch May 6, 2013, 19:58

    “Making a black whole goes squarely in the NO category if “realistic” is supposed to play any part in the equation.”

    It is as realistic as it gets. There is nothing else that comes close. You might consider creating a small black hole in the same category as wormholes and warp drive but the idea of using gargantuan solar energy collectors is not in the worm hole catergory and neither is a gamma ray laser.

    If you want realistic as in what you can build in your garage you are commenting on the wrong forum.

  • Eniac May 6, 2013, 22:04

    It is simply astonishing that you equate fissioning heavy elements with creating a small black hole. No two phenomenon could be more different.

    What Rob is saying, correctly, is that to create a black hole you need to contain an awful lot of energy into an awfully tiny space. Same with fusion. Only fusion is 40 orders of magnitude easier.

    Antimatter is also MUCH easier to make, gives you the same fuel mass to energy efficiency and does not come with that awkward trade-off between too heavy and too short-lived.

    If you want to hear my version of space propulsion technology: Nuclear or solar electric right now, to fly around in the solar system. Fission fragment rockets for the first interstellar probes. Fusion versions of both when the technology is ready. Maybe antimatter some longish time later. Black holes: probably never.

  • Ron S May 7, 2013, 19:41

    Gary: “It is simply astonishing that you equate fissioning heavy elements with creating a small black hole. No two phenomenon could be more different. ”

    I never said they were the same. Go back and read what I did say regarding the trait they most definitely do share. I can’t tell if you are deliberately avoiding the topic or that you just do not understand. Only with that understanding will you be in a position to discuss confinement in regards to fusion and the creation of spacetime horizons.

  • william f collins May 8, 2013, 13:40

    Gary
    You touched on a key piece for space travel – the medical items. It is quite possible that there will be faster or more sure fire developments re: human “adaptive” augmentations or life expectancy enhancements as opposed to unlikely wormhole /FTL/warp drive “propulsion” systems for deep space/interstellar travel. Humans who are longer-lived and who are more adaptive to space travel will be our future interstellar travelers. I would bet that the extensive experience gained from future exploration/exploitation of the interplanetary milieu will prepare humans for that leap to Alpha Centauri

  • D. Wayne Dworsky May 11, 2013, 8:52

    It’s just a matter of time. We are on the verge of discovering great new world in the vast ocean of space. We are at the forefront, looking out into space as did Christopher Columbus when he set out over the Atlantic in 1492. We’re living in a marvelous time. By pooling our efforts as a species (international cooperation) we can figure out how to beat the speed limit Albert Einstein set in his theory of relativity.

  • william f collins May 12, 2013, 7:32

    I absolutely agree that the the current international cooperation for NEO projects will have to continue on an even larger scale as humankind expands into interplanetary space. I strongly suspect that the Einstein “speed limit” is going to be insurmountable. Christopher Coumbus is a dubious model for discovery of new worlds since there were already human inhabitants (“intelligent life”) who had discovered the New World 14,000 year prior to Columbus showed up.

  • ljk May 28, 2013, 13:48

    No Planet of Alpha Centauri B?

    By Mark Zastrow

    The uncertain tale of our closest exoplanet neighbor — is it there or isn’t it? — may end on a cliffhanger.

    This artist’s impression of the Alpha Centauri system shows Alpha Centauri B at center, with its planet candidate in crescent phase. The companion star Alpha Centauri A is at left, while the faint dot in the upper right is our Sun.
    ESO/L. Calçada/Nick Risinger (skysurvey.org)

    Last October astronomers announced big news: The discovery of a rocky, scorching hot, Earth-sized planet circling our closest stellar neighbor, the orange dwarf star Alpha Centauri B just 4.3 light-years away. Exoplanet astronomer Debra Fischer (Yale) told the New York Times that the planet next door was the “story of the decade.”

    Almost lost in the excitement was the caveat that the planet’s detection was still iffy and required heroic efforts to extract any sign of it from the background noise of the star’s radial-velocity measurements.

    Now the plot has become more muddled. A new analysis of the data by an independent researcher has failed to confirm the planet’s existence.

    The new study, by Artie Hatzes (Thuringian State Observatory, Germany), is not a death sentence for Alpha Cen Bb, as it’s named. But both sides say it illustrates the need for more data collection and confirmation before it is accorded full planethood — or, Hatzes adds, feted by the media. “Although big discoveries are exciting, they should be treated with caution,” he says.

    Full article here:

    http://www.skyandtelescope.com/news/Exoplanet-in-Alpha-Centauri-remains-unconfirmed-208860591.html

Next post:

Previous post: