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Voyager: Looking Backward and Forward

The Voyager spacecraft have run into their share of problems as they move toward true interstellar space, but on the whole their continued operations have been a testament to what well designed equipment can do. Voyager 2’s camera platform locked for a time not long after the Saturn flyby but controllers were able to restore the system by experimenting with similar actuators on Earth. Three years ago the craft began having data problems resulting from a flipped bit in an onboard computer but a reset from Earth corrected the fault. Even the failure of the primary radio receiver not long after launch was resolved by the use of the onboard backup.

Obviously both craft are living on borrowed time as the power output of their radioisotope thermoelectric generators (RTGs) continues to decline, but we should still be getting signals for another decade or so. With the Voyagers now on what is designated their ‘interstellar mission,’ it’s pleasing to note that Alpha Centauri is the guide star that Voyager 1 used to reorient itself to resume transmissions to Earth following 2011 maneuvering to allow better detection of the solar wind. We continue to push deeper into a region of space that is now little understood.

Leaving the Solar System

Yesterday’s brief skirmish over Voyager 1’s true situation tells us how much we have to learn about the Solar System’s edge. A paper by William Webber (New Mexico State) and the late Frank McDonald (University of Maryland) reported that a sudden change in cosmic rays detected by Voyager 1 last summer showed that the spacecraft was in a new region of the Solar System they called the ‘heliocliff.’ What evidently confused matters was that the American Geophysical Union, publisher of Geophysical Review Letters — the publication at which the paper had been accepted — sent out a news release saying the craft had left the Solar System.

While the cosmic ray changes were marked, with galactic cosmic ray intensity suddenly doubling last August, Caltech’s Ed Stone issued a statement saying that a change in the magnetic field will be the true indication of Voyager 1’s arrival in interstellar space. No such change has yet been detected, and the AGU soon revised the news release headline to say that the spacecraft had ‘entered a new region of space.’ The ‘heliocliff,’ in other words, is apparently the same region that NASA scientists had already noted as a previously unknown ‘highway’ of magnetic particles. Nancy Atkinson straightened all this out quickly on Universe Today.

So Voyager 1 hasn’t yet left the Solar System, even if it is in a curious boundary region we’re still learning about. Stone said last December that he believes true interstellar space may be months or at most a couple of years away. Whenever the transition does occur, it will mark our species’ first penetration of the realm beyond the heliosphere, and we’re fortunate indeed to have two spacecraft still functional enough to report back their findings as it occurs. After all, the Voyagers were never designed to be interstellar craft and have far exceeded our expectations.

Titan_3E_with_Voyager_1

Image: The launch of Voyager 1 on September 5, 1977. Credit: NASA.

Voyager and the Archaeological Record

Meanwhile, another take on the Voyagers was offered up last January at the World Archaeology Conference in Jordan, where the spacecraft were treated as artifacts of our civilization. Colleen Beck (Desert Research Institute) and Ben McGee (Astrowright Spaceflight Consulting LLC) looked at the probes as meaning-bearing objects with or without their famous ‘Golden Records,’ markers of the culture that made them. Their presentation was titled “The bottle as the message: Solar System escape trajectory artifacts.” Matthew Battles uses Beck and McGee’s work as a launching pad for his own insights into the Voyagers in The Ache for Immortality.

Surely the Golden Records will never be snared by an extraterrestrial civilization, but compiling them taught us much about ourselves and our need to be remembered. Carl Sagan wrote about the Golden Record project in Murmurs of Earth (1978) where, Battles reminds us, he invoked the name of Esarhaddon, a 7th C. BC Assyrian king who saw to it that plaques were placed in the foundations of monuments in his kingdom as messages to the future. Thus the idea of a votive impulse focused not on the gods but rather posterity, an impulse to connect with successor generations that appears to be hard-wired in the species.

It turns out that another probe designed for our descendants is already in space. The Laser Geodynamic Satellite (LAGEOS) was launched in 1976 and joined by a second LAGEOS in 1992, both designed to study continental drift. Battles describes the satellite as a ball of brass more than half a meter in diameter, weighing 450 kg and carrying no instrumentation. The working principle is that ground-based lasers use the satellites to measure accurate distances, allowing scientists to detect tiny movements in the Earth’s crust. LAGEOS is in an orbit that will take over 8 million years to decay. It, too, contains a plaque, this one showing Earth’s continents over 16 million years of projected continental drift, a kind of time capsule in its own right.

What to make of gestures like this? From the essay:

There is a peculiar quality in these plaques and golden records — a compound of the Quixotic and the Ozymandian; an acknowledgement of our cosmic insignificance, paired with pride in the craft that pries that knowledge loose from the world — which is deeply characteristic of science in the late 20th century. Sagan stated as much when he wrote of the first Voyager mission, ‘the launching of this “bottle” into the cosmic “ocean” says something very hopeful about life on this planet’ — a hope that, however slim, was still vastly greater than the chance that one of the Voyagers would ever encounter life elsewhere. These messages in a bottle were among the more telling transmissions in a mythology of wonder that American science generated in the mid-20th century — an attempt, through science itself, to preserve a record of life on Earth, in light of destructive powers unleashed by science in the atomic age.

But an archaeological look at human monuments scattered throughout the Solar System — probes in long orbits, abandoned equipment on the Moon, networks of communications satellites — might see them in the same light that we now examine Esarhaddon’s works, for, as Battles puts it, “…like the monuments of ancient Mesopotamia, they embody our wonder tales as well.” I think any future archaeologist, human or otherwise, would read into the Voyager spacecraft the desire of a species to transcend itself, hopeful of finding a bridge to other intelligence but pressing on regardless as a way of building meaning into the cosmos.

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  • ljk March 21, 2013, 10:43

    ‘Friends of Space, How Are You All? Have You Eaten Yet?’ Or, Why Talk to Aliens Even if We Can’t

    Trevor Paglen

    In late 1971 science reporter Richard Hoagland climbed up the metal ladder at the hangar-like thermal-vacuum test facility at TRW Systems in Redondo Beach, just south of Los Angeles. It was dark. Inside a cavernous chamber, the Pioneer 10 spacecraft was undergoing a week-long test regimen designed to simulate the vacuum and extreme temperatures of deep space. As he climbed up towards the quartz-glass viewing window, Hoagland could see light emanating from the chamber.

    Pioneer 10 was going to do something unprecedented. The spacecraft would mark humanity’s first venture towards the outer planets and would deliver the first close-up pictures of Jupiter on a fly-by of the great gas giant. But there was something else. On its fly-by, Pioneer would accumulate so much speed from the slingshot effect of Jupiter’s gravity that it would achieve escape velocity from the sun. After studying Jupiter, Pioneer would hurtle on towards the infinite blackness of interstellar space.

    Full article here:

    http://www.afterall.org/journal/issue.32/friends-of-space-how-are-you-all-have-you-eaten-yet-or-why-talk-to-aliens-even-if-we-can-t

    To quote:

    Despite the Record’s grand ambition, the team deliberately veered away from anything controversial: ‘We reached a consensus that we shouldn’t present war, disease, crime and poverty,’ Lomberg recounted. ‘We felt that we were making something that would survive us and our time — something that might be the only token of earth the universe would have. We decided the worst in us needn’t be sent across the galaxy.’15

    Furthermore, the team wanted to ‘avoid any political statement’ or any images that might ‘seem threatening or hostile to recipients (“Look how tough we are”), which is why we didn’t send a picture of a nuclear explosion’.16There are no religious images (‘there are so many human religions that if we had shown any, we felt we would have to give equal time to all’).

    No images of art (‘mostly because we didn’t feel competent to decide what art should be sent… And we thought extraterrestrials would have enough trouble interpreting photographs of reality or simple diagrams without including a photograph of a painting, which in itself is an interpretation of reality’).17

  • GaryChurch March 21, 2013, 11:25

    That picture of a Titan reminds me of the SLS soon to come. Very exciting!
    70 tons to LEO equals a large payload to escape velocity. Like the Webb if they ever get it finished.

    “-in light of destructive powers unleashed by science in the atomic age.”

    Now we have other worries, both external and internal. While a nuclear winter may have killed off most of civilization a small rock can throw enough debris into the atmosphere to start world war C (the c is for cannibalism).
    And internally we have to worry about a modest backwater lab somewhere letting the geni out of the bottle- an engineered pathogen that unlike a naturally evolved bug would leave no survivors.

    We need a Moonbase as a survival colony and from which to launch nuclear interceptor missions.

  • NS March 21, 2013, 14:19

    All of the probes, monuments etc. had immediate or near-term usefulness for the people that created them. Their longer-term usefulness (if any) was luck. And there’s a selection effect — old things that aren’t useful get thrown away or destroyed to make way for the new. The plaques and records for future generations were more or less afterthoughts. There’s nothing wrong with that; in fact it’s the right approach to take when trying to guess what the future may be interested in. What doesn’t make sense is building something that may be useful only (if ever) in a distant future whose interests we can have no clue about. Chances are it will end up as little more than an expensive time capsule.

  • ljk March 21, 2013, 14:58

    Paul Gilster said in his article above, and I quote:

    “Surely the Golden Records will never be snared by an extraterrestrial civilization, but compiling them taught us much about ourselves and our need to be remembered.”

    Paul, shame on you! :^) About the ETI never finding either of the Voyager Interstellar Records (and by default I bet you also meant the two Pioneer Plaques). Yes the odds are slim, but they do improve for the chances of terrestrial descendants finding one of them. However, our future “children” may be so different from us they might as well be alien.

    Paul then said:

    “Carl Sagan wrote about the Golden Record project in Murmurs of Earth (1978) where, Battles reminds us, he invoked the name of Esarhaddon, a 7th C. BC Assyrian king who saw to it that plaques were placed in the foundations of monuments in his kingdom as messages to the future. Thus the idea of a votive impulse focused not on the gods but rather posterity, an impulse to connect with successor generations that appears to be hard-wired in the species.”

    That ancient ruler’s name was used for S. R. Hadden in Sagan’s Contact, the powerful and smart rich guy, played notably by John Hurt in the 1997 film version, who was basically a demigod, living in the sky most of the time and manipulating people and events at his whim.

    By the way, Sagan was also heavily involved in the creation and making of the LAGEOS plaque, which was used as one of the 118 photographs in the Voyager Records to denote Earth’s continental drift. The original design came from the book Planets of the Time-Life Science series first published in 1966, which had Sagan as its science consultant. His influence there was quite obvious based on his later works.

    If you look at this closeup of the Voyager 6 (V’Ger) Plaque from the 1979 film Star Trek: The Motion Picture, you can see the diagram from LAGEOS on the far right (scroll down the article):

    http://hilobrow.com/2013/02/03/voyager-ex-voto/

    Is that article by Beck and McGee available online anywhere? All I can find of it is the abstract from the conference:

    http://www.academia.edu/2463507/The_bottle_as_the_message_Solar_System_escape_trajectory_artifacts

  • ljk March 21, 2013, 15:56

    So Beck and McGee (and Battles) say that the space probes carrying the plaques, the records, and whatever other direct information about their makers and their world are just as valuable if not more so as “meaning-bearing objects”.

    https://www.conftool.com/wac7/index.php?page=browseSessions&search=bottle+as+the+message

    Fair enough. Obviously they are (or were) functioning representations of the technological sophistication level of the species which launched them. Without their existence, the plaques and records would likely never have been made, to say nothing of the exploration of numerous alien worlds being delayed or having yet to happen.

    Do not forget that all five vessels leaving our Sol system are also being trailed by the last stages of the rockets that got them into space, so make that ten major human artifacts heading out into the wider Milky Way galaxy. Note that all five boosters are lacking any information packages on them, so far as I know. Many do (or did) not even realize (or care) that they were sailing on their own trajectories into the void.

    Nevertheless, it is rather presumptuous to declare that our first interstellar probes (and any other deep space vessel) would be sufficient in and of themselves to explain to anyone who finds them (presumably an intelligence that did not originate from Earth) about the beings that made them and the place they came from. Find me the archaeologist who would not appreciate or care about having a written or visual document accompanying some ancient artifact they found, and I will show you a nonprofessional on his or her way to creating a cult.

    If an alien probe was discovered moving through our Sol system, would we not want to know exactly what it is, what is its purpose, and why is it in our celestial neck of the woods? Do you honestly think the human populace would be reassured by some scientist declaring his or her assumption that the alien vessel is not a threat to us just by looking at it and guessing at the motives of an alien mind? Or would it help significantly if the ETI makers of this spacecraft put some kind of information about themselves and the vessel’s mission made with the intent of being understood by those different from them? I suspect the reverse will also be true for those who will come across our interstellar machines one day in deep space.

    I can also say with confidence that the multiple values of and interest in the EchoStar XVI communications satellite placed in geosynchronous orbit last November rose significantly with the addition of The Last Pictures art project encased in a golden container and attached to its hull.

    https://centauri-dreams.org/?p=26171

    Otherwise how many here and elsewhere would have paid much attention to the lofting of yet another commercial comsat on a mission to beam cable television programming to millions of couch potatoes?

    Methinks that Beck and McGee (and Battles) are getting a wee bit too caught up in the romanticism and mysticism of finding some mysterious object from another place and time. A fictional mystery for entertainment purposes and even engagement is fine, but science demands empirical evidence. Too much ambiguity not only threatens to have the true meaning of an artifact be muddled or misinterpreted, but could even cause an otherwise important piece of history and knowledge be outright rejected by science, creating a tragic lost opportunity.

    So play around with mystery stories and romantic adventures for a bit if you want, but make sure there is an operator’s manual handy when you actually need to know what that strange alien thing is really about!

  • ljk March 21, 2013, 16:34

    Quoting Paul Gilster in the very last sentence of the very last paragraph of his article above:

    “I think any future archaeologist, human or otherwise, would read into the Voyager spacecraft the desire of a species to transcend itself, hopeful of finding a bridge to other intelligence but pressing on regardless as a way of building meaning into the cosmos.”

    Carl Sagan had similar things to say about the Voyager Interstellar Records in the Epilogue to Murmurs of Earth:

    “But one thing would be clear about us: No one sends a message on such a journey, to other worlds and beings, without a positive passion for the future. For all the possible vagaries of the message, they could be sure that we were a species endowed with hope and perseverance, at least a little intelligence, substantial generosity and a palpable zest to make contact with the cosmos.”

  • Paul Gilster March 21, 2013, 16:46

    ljk writes:

    That ancient ruler’s name was used for S. R. Hadden in Sagan’s Contact, the powerful and smart rich guy, played notably by John Hurt in the 1997 film version, who was basically a demigod, living in the sky most of the time and manipulating people and events at his whim.

    I certainly remember S. R. Hadden from the movie but hadn’t put it together with Esarhaddon! Very glad you mentioned this.

  • ljk March 21, 2013, 17:43

    In the 1985 novel version of Contact, S. R. Hadden has himself flung out of the Sol system (with some help from Jupiter, though he wanted to flyby Saturn for the view) with the hope that the natural intense cold of deep space will eventually seep into his spacecraft to freeze and preserve him, to be revived in a future time and place somewhere else in the galaxy. How’s that for a “meaning-bearing” object!

    In the 1997 film version, Hadden (played by actor John Hurt) died of cancer while living aboard the Soviet/Russian space station Mir (to stave off the disease). The resident cosmonauts had him “buried” in space in a manner similar to sailors being buried at sea from a nautical ship.

    Ironically, John Hurt’s character in the classic 1979 SF film Alien was also buried in space from the Nostromo, after he had died from quite different and much messier circumstances.

    And I quote from Chapter 22 of the novel:

    In two years, this flying sarcophagus would fall into the gravitational potential well of Jupiter, just outside its radiation belt, be slingshot around the planet and then flung off into interstellar space. For a day he would have a view still more spectacular than that out the window of his study on Methuselah—the roiling multicolored clouds of Jupiter. the largest planet.

    If it were only a matter of the view. Hadden would have opted for Saturn and the rings. He preferred the rings. But Saturn was at least four years from Earth and that was, all things considered, taking a chance. If you’re stalking immortality, you have to be very careful.

    At these speeds it would take ten thousand years to travel even the distance to the nearest star. When you’re frozen to four degrees above absolute zero, though, you have plenty of time. But some fine day—he was sure of it, though it be a million years from now—Gilgamesh would by chance enter someone else’s solar system. Or his funeral bark would be intercepted in the darkness between the stars, and other beings—very advanced, very far-seeing—would take the sarcophagus aboard and know what had to be done.

    It had never really been attempted before. No one who ever lived on Earth had come this close. Confident that in his end would be his beginning, he closed his eyes and folded his arms experimentally across his chest, as the engines flared again, this time more briefly, and the burnished craft was sleekly set on its long journey to the stars.

    Thousands of years from now, God knows what would be happening on Earth, he thought. It was not his problem. It never really had been. But he, he would be asleep, deep-frozen, perfectly preserved, his sarcophagus hurtling through the interstellar void, surpassing the Pharaohs, besting Alexander, outshining Qin. He had contrived his own Resurrection.

  • will March 21, 2013, 19:15

    @GaryChurch

    “-in light of destructive powers unleashed by science in the atomic age.”

    Now we have other worries, both external and internal. While a nuclear winter may have killed off most of civilization a small rock can throw enough debris into the atmosphere to start world war C (the c is for cannibalism).
    And internally we have to worry about a modest backwater lab somewhere letting the geni out of the bottle- an engineered pathogen that unlike a naturally evolved bug would leave no survivors.

    – what are you talking about?

  • James Jason Wentworth March 22, 2013, 9:20

    ljk wrote (in part):

    [Do not forget that all five vessels leaving our Sol system are also being trailed by the last stages of the rockets that got them into space, so make that ten major human artifacts heading out into the wider Milky Way galaxy. Note that all five boosters are lacking any information packages on them, so far as I know. Many do (or did) not even realize (or care) that they were sailing on their own trajectories into the void.]

    According to a Wikipedia article on human-made objects that are escaping from the solar system, Pioneer 11’s spent solid propellant third stage isn’t on an escape trajectory but is in a wide-ranging solar orbit instead. That sounds right, because Pioneer 11 was tossed above the ecliptic by Jupiter and “back” across the solar system to encounter Saturn, and Pioneer 11 had to make several mid-course burns (which its spent third stage couldn’t do) to aim itself to reach Saturn. Nonetheless, your point is an excellent one–those spent stages were potential “canvases” that could have carried additional messages…and speaking of “cosmic message bottles”:

    There is another, relatively cheap way that such physical messages could be launched into interstellar space. As Arthur C. Clarke mentioned on page 134 of “The Promise of Space”:

    “The first manmade objects ever to leave the Earth were small metal pellets launched by an explosive charge on an Aerobee rocket 50 miles above New Mexico on October 16, 1957. One of these artificial meteors attained a speed of 33,000 mph–far in excess of escape velocity. The experiment was conceived by Professor Fritz Zwicky of the California Institute of Technology.” Now:

    Similar projectiles (containing chip-encoded images, text, and audio, perhaps) could be fired from sounding rockets so that they would pass by Jupiter and be ejected from the solar system. In this way, multiple (and even updated, over time) interstellar messages could be sent to the stars. Also:

    If folks living around another star detected (which would require some fancy technology, indeed!) trains or swarms of such “anomalous meteoroids” passing rapidly through their stellar system, they might capture some to examine. “Molded-in” optical and/or microwave radar corner reflectors would make the projectiles unusually bright for their size. In addition:

    Launching such interstellar message projectiles might even become a “cultural business,” not unlike the companies which space enthusiast ordinary citizens pay to beam their personal radio messages to the stars.

  • GaryChurch March 23, 2013, 13:41

    “– what are you talking about?”

    I commented on the view that voyager was in part a response to the possibility of nuclear armageddon. Now we have other problems like impacts and plagues.

  • ljk March 25, 2013, 10:33

    Some earlier Centauri Dream articles have dealt with small-size interstellar probes, such as Mason Peck’s Sprites, also known as Spacecraft on a Chip:

    https://centauri-dreams.org/?p=18968

    Needle probes – whole swarms that perhaps have the task of gathering and relaying just a few bits of information on a target star system, yet as a whole can do more than any one large yet contained probe:

    https://centauri-dreams.org/?p=255

    Really tiny engines called NanoFETs:

    https://centauri-dreams.org/?p=8647

    I certainly recognize that small probes would be vulnerable to cosmic radiatin and other dangers while traveling at relativistic speeds through the galaxy. Plus they will need some form of propulsion to get them there relatively quickly. So we will still need some kind of large vessel, even if it is primarily a transport. But the probes themselves need not be a mere handful of multiton behemoths, with all due respect to Daedalus.

  • ljk March 25, 2013, 11:08

    GaryChurch said on March 23, 2013 at 13:41:

    “I commented on the view that voyager was in part a response to the possibility of nuclear armageddon. Now we have other problems like impacts and plagues.”

    As I pointed out in my Centauri Dreams article on Trevor Paglen’s The Last Pictures art project (https://centauri-dreams.org/?p=26171), David Zondy made a similar observation regarding the Voyager Records here:

    http://davidszondy.com/future/timecapsule/voyager.htm

    While we are certainly not out of the woods when it comes to a nuclear war (North Korea and Iran come to mind as just two current examples), few would have imagined when the Records were sent heavenward in 1977 that in a matter of mere years the USA and former USSR would no longer be deadly Cold War enemies and have gotten rid of tens of thousands of nuclear weapons between them.

    While Sagan and company were certainly wondering if their golden creations might indeed be among the last objects ever made by their species to survive should someone on Earth have pressed the proverbial button (anyone who was alive and aware during the Cold War era who did not at least ponder such things once in a while was truly not paying attention to global issues), they also saw it much more strongly as a symbol of hope for their species, that we could literally transcend our primitive problems and one day literally follow the Voyagers to the stars.

    Ironically, Paglen viewed the Records as signs of “old-fashioned” optimism, causing him to make a message to the present and future displaying our less enlightened and pleasant sides.

    The point I am trying to make is that humanity has been through far worse situations than we are in now, such the Great Plague that ravaged Medieval Europe, the Great Depression of the 1930s and the Second World War that followed. Anyone living during those times could be easily forgiven if they felt that humanity was on its way to an end to civilized society or even extinction.

    In many ways we are in a better position than ever before to solve our problems – if we have the will and ability to rise above our animal and tribal natures. I do not exaggerate when I say that we supporters of space exploration and colonization can and should play an important and even vital role in literally and socially uplifting our fellow humans.

    Do not make the Voyager Records and the EchoStar XVI Artifact be among the last things our species ever does of lasting effort.

  • GaryChurch March 25, 2013, 15:24

    “In many ways we are in a better position than ever before to solve our problems”

    If anything can be called a double edged sword it is technology; my biggest fear is an engineered pathogen.

    It would not leave survivors.

    And that is why we need survival colonies in space. Several.

  • Eniac March 25, 2013, 22:24

    It would not leave survivors.

    And you know that, how???

  • GaryChurch March 26, 2013, 12:21

    It would not leave survivors.
    “And you know that, how???”

    If I was designing a bioterror weapon I would want it as lethal as possible- and it is of course possible to make a completely lethal bug. Several organisms, like anthrax, come pretty close. Just tweeking some virus in a modest lab could be the end of humankind. Really.

  • Eniac March 28, 2013, 0:40

    “… and it is of course possible to make a completely lethal bug.”

    Of course. I admire the unmitigated certainty of your conviction, in total disregard of the substantial body of biological and epidemiological evidence which indicates otherwise. It reminds me of blind faith and religious extremism…

    “Several organisms, like anthrax, come pretty close.”

    And yet, anthrax has never been a serious threat, because it does not spread. The deadlier a disease, the less likely it is to spread. Non-contagious diseases only effect those directly exposed, and contagious ones are very effectively counteracted by isolation and quarantine.

    Ebola is a good example. It is very contagious, and very deadly, and precisely because of that outbreaks do not turn epidemic (i.e. stay locally confined).

    And that is only epidemiology. Biologically, you have to deal with the immune system, which is extremely variable and flexible. Only equally variable and flexible organisms (such as AIDS, for example) have a chance to effectively evade it for long. However, if you design your organism to be flexible, it will rapidly lose its virulence. If you want to retain the virulence, you have to make it stable and thus an easy prey for the immune system. Anthrax uses speed to overwhelm the immune system before it can react, but that deprives it of the ability to spread, because the incubation time is much too short.

    None of these of course are certain conclusions, and you may have a point, but that absolute certainty you display is born of naive, simplistic reasoning and totally unjustified in light of the evidence.

  • GaryChurch March 28, 2013, 14:51

    “-that absolute certainty you display is born of naive, simplistic reasoning and totally unjustified in light of the evidence.”

    That absolute certainty you display is………contrary to what some of the smartest people on Earth say. I will go with their advice.

    Stephen Hawking
    famous cosmologist who discovered that black holes are not completely black, but emit radiation and eventually evaporate and disappear.

    “It is important for the human race to spread out into space for the survival of the species. Life on Earth is at the ever-increasing risk of being wiped out by a disaster, such as sudden global warming, nuclear war, a genetically engineered virus or other dangers we have not yet thought of.”

    “In the long term, I am more worried about biology. Nuclear weapons need large facilities, but genetic engineering can be done in a small lab. You can’t regulate every lab in the world. The danger is that either by accident or design, we create a virus that destroys us.”

    “I don’t think the human race will survive the next thousand years, unless we spread into space. There are too many accidents that can befall life on a single planet.”

    Charles Krauthammer
    syndicated columnist who appears in the Washington Post and other publications and commentator on various TV programs. He earned his M.D. from Harvard University’s medical school in 1975 and won the Pulitzer Prize in 1987.

    “Resurrection of the [1918 Flu] virus and publication of its structure open the gates of hell. Anybody, bad guys included, can now create it. Biological knowledge is far easier to acquire for Osama bin Laden and friends than nuclear knowledge. And if you can’t make this stuff yourself, you can simply order up DNA sequences from commercial laboratories around the world that will make it and ship it to you on demand…

    And if the bad guys can’t make the flu themselves, they could try to steal it. That’s not easy. But the incentive to do so from a secure facility could not be greater. Nature, which published the full genome sequence, cites Rutgers bacteriologist Richard Ebright as warning that there is a significant risk “verging on inevitability” of accidental release into the human population or of theft by a ‘disgruntled, disturbed or extremist laboratory employee.’

    Why try to steal loose nukes in Russia? A nuke can only destroy a city. The flu virus, properly evolved, is potentially a destroyer of civilizations.

    Ray Kurzweil
    prophetic author of the 1990 book The Age of Intelligent Machines where he correctly predicted advancements in AI. He was also the principal developer of the first omni-font optical character recognition, the first print-to-speech reading machine for the blind, the first CCD flat-bed scanner, and the first commercially marketed large-vocabulary speech recognition. He is a member of the U.S. Army Science Advisory Group, our 2005 Guardian Award winner, and is on our Scientific Advisory Board.

    “…the means and knowledge will soon exist in a routine college bioengineering lab (and already exists in more sophisticated labs) to create unfriendly pathogens more dangerous than nuclear weapons.”

    “I advocate a one hundred billion dollar program to accelerate the development of technologies to combat biological viruses.”

    “We have an existential threat now in the form of the possibility of a bioengineered malevolent biological virus. With all the talk of bioterrorism, the possibility of a bioengineered bioterrorism agent gets little and inadequate attention. The tools and knowledge to create a bioengineered pathogen are more widespread than the tools and knowledge to create an atomic weapon, yet it could be far more destructive. I’m on the Army Science Advisory Group (a board of five people who advise the Army on science and technology), and the Army is the institution responsible for the nation’s bioterrorism protection. Without revealing anything confidential, I can say that there is acute awareness of these dangers, but there is neither the funding nor national priority to address them in an adequate way.”

    “The decision by the U.S. Department of Health & Human Services to publish the full genome of the 1918 influenza virus on the Internet in the GenBank database is extremely dangerous and immediate steps should be taken to remove this data.”

    “Grey goo certainly represents power — destructive power — and if such an existential threat were to prevail, it would represent a catastrophic loss… Although the existential nanotechnology danger is not yet at hand, denial is not the appropriate strategy.”

    “A self-replicating pathogen, whether biological or nanotechnology based, could destroy our civilization in a matter of days or weeks.”

    John Leslie
    author of The End of the World: The Science and Ethics of Human Extinction and a member of our Scientific Advisory Board.

    “Our failure to detect intelligent extraterrestrials may indicate not so much how rarely these have evolved, but rather how rapidly they have destroyed themselves after developing technological civilizations.”

  • GaryChurch March 28, 2013, 15:53

    “The danger is that either by accident or design, we create a virus that destroys us.”

    http://www.airforcetimes.com/news/2013/03/gannett-bioterror-lab-risks-remain-high-agencies-say-032513/

    I do not think your characterization of my fear of a super virus is accurate. Perhaps you might want to reevaluate your own “naive, simplistic reasoning.”

  • Eniac March 28, 2013, 23:44

    That absolute certainty you display is………contrary to what some of the smartest people on Earth say.

    I think if you go back and reread what I said, this time taking the trouble of actually understanding it, you will have to admit that, unlike you, I did NOT display any absolute certainty of any kind.

  • Eniac March 28, 2013, 23:48

    None of the many wonderful thinkers you cite supports your simple, yet blatantly made-up statement: “It would not leave survivors.”

  • GaryChurch March 29, 2013, 16:49

    “I did NOT display any absolute certainty of any kind.”

    I think you did; you are absolutely certain I am wrong.

    None of the many wonderful thinkers you cite supports your simple, yet blatantly made-up statement: “It would not leave survivors.”

    {Life on Earth is at the ever-increasing risk of being wiped out by a} disaster, such as sudden global warming, nuclear war, a {genetically engineered virus} or other dangers we have not yet thought of.
    In the long term, I am more worried about biology. Nuclear weapons need large facilities, but genetic engineering can be done in a small lab. You can’t regulate every lab in the world. {The danger is} that either by accident or design, we create {a virus that destroys us}.

    {Life on Earth is at the ever-increasing risk of being wiped out by a}{genetically engineered virus}

    {The danger is}{a virus that destroys us}.

    I think you are blatantly making things up, not me. Unless you want it word for word then one wonderful thinker did say no survivors. Unless you think I misinterpreted those statements by Stephen Hawking.

  • GaryChurch March 29, 2013, 16:57

    http://online.sfsu.edu/rone/GEessays/killervirus.html

    We can keep beating this horse or we can move on to another topic Eniac.

  • Eniac March 29, 2013, 17:36

    Unless you think I misinterpreted those statements by Stephen Hawking.

    I do, indeed. I am sure he would be the first to admit he was taking dramatic license, and would never seriously try to run roughshod over the finer points of epidemiology. He is a theoretical physicist, after all, not a biologist.

  • GaryChurch March 30, 2013, 13:54

    “He is a theoretical physicist, after all, not a biologist.”

    Good point. And maybe a fraction of a percent of humanity might survive a designer killer small pox plague. Perhaps life will find a way. You may be right Eniac.

    But while the difference between extinction and a depopulated humanity coming back from the brink is huge, the magnitude of such a catastrophe would be more than most minds could bear.

  • Rob Henry March 30, 2013, 17:42

    GaryChurch, what is this beating a horse business? Surely the discussion has only just started to become interesting.

    Unlike ENIAC (I think?), I have little doubt that it can, or soon will, be possible to engineer a virus that, if inoculated into everyone simultaneously, would leave zero to a handful of survivors. However it is very hard to come up with a scheme whereby most infections do not occur after they have been cycled through several other people first. Under such circumstances we would have to stop with many attenuated strains, activating their immune system against the epitopes of the virulent strain. So how can we overcome that problem?

    Our virus can replicate abnormally slowly and with high fidelity, yet still outpace the immune system. At least it could if, neither it, nor some of its transformed cells, expressed no epitopes remembered by the immune system.

    I was going to go no, but perhaps that’s sufficient. I would, however, like to note though, that if AIDS had been as infectious as it is now when it originated, it would have probably saturated its core group, and moved out into a large portion of the general population before it was even discovered. Not only would this have bankrupted our medical care system, but this large group of immunosuppressed would have seen the re-emergence of diseases such as antibiotic resistant tuberculosis in the non-HIV infected remainder of the population. Humans might survive but could civilisation?

  • Eniac March 30, 2013, 19:49

    Life has always found a way. For billions of years no cosmic catastrophe has had more than a minor dent in the planet’s populations. We call those mass extinctions, but that is a bit of an overdramatization.

    Our technological civilization may be more fragile than that (although you could argue the opposite), but then, civilizations are quite ephemeral, anyway. They do not last longer than a few hundred years, usually to be replaced by another, upstarts or invaders. And if you take the replacement of animal power by steam as the starting point, it took only about 200 years for all of our high technology to be created. This can always happen again.

    The fact is, neither impacts, nor total nuclear war, nor engineered organisms have the capacity to do more than temporary damage to the Earth’s populations. Although, minus the absolute statements, I agree with you that engineered pathogens would be somewhere near the top of the list, somewhere behind runaway nanotechnology, super AI, and antimatter pocket bombs.

  • ljk April 1, 2013, 10:37

    I think it is a testimony to life on Earth in general that in the four or so billion years there have been organisms on this planet, that we have not gone lifeless at some point, despite nature’s best efforts such as giant space rocks and supernovae radiation. Oh sure we have been rendered low numerous times, but never totally out (obviously).

    Even the Black Plague, which supposedly wiped out half of Europe in the Middle Ages when they knew nothing of microbiology and the methods employed to try and stop the plague were either largely ineffective or just made things worse, could not and did not kill everyone. In fact I read how there is evidence that surviving people began building up a natural defense to the plague in a few years after its arrival even without antibiotics. Note too how it also had the ironic result of triggering significant cultural and intellectual changes in Europe which resulted in the Renaissance, which led to the Enlightenment and onward to our modern civilization.

    This bodes well for us and for other life-bearing worlds in the Universe – though how many will have organisms that survive long enough to be technological and have space travel is another matter.

  • GaryChurch April 1, 2013, 13:24

    “The fact is, neither impacts, nor total nuclear war, nor engineered organisms have the capacity to do more than temporary damage to the Earth’s populations.”

    I used the paraphrase “life finds a way” from the movie Jurassic Park for a reason. The Dinosaurs did not find a way- and though we are a little smarter that does not take us off the endangered species list.

    The Permian extinction was not temporary damage by the way. It almost killed all complex life. You are intimating it will never happen again- I am saying it is inevitable. And since for practical purposes, it is a random event, I believe in this argument I am the one who comes out as being selected for survival and you for extinction.

  • Eniac April 1, 2013, 22:23

    It almost killed all complex life.

    Another one of your brash dramatizations. It did not “kill” all, not even “almost”. It was a change in types of organisms, probably caused by a drastic change in environment. There was not the slightest change that life itself was endangered.

    and though we are a little smarter that does not take us off the endangered species list

    So you claim. However, our technology totally changes the game, which may push us onto the list or take us off. Nobody really knows. Not even you, contrary to your attitude.

  • Eniac April 1, 2013, 22:35

    And, what, the damage from the Permian extinction was not temporary? What is that supposed to mean?

  • GaryChurch April 2, 2013, 13:08

    “-a change in types of organisms, probably caused by a drastic change in environment-”

    Kind of like global warming is not really “warming”- it is global “climate change.”

    I understand now. You really ARE selecting humankind for extinction.

  • GaryChurch April 3, 2013, 12:03

    http://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event

    Everyone else on Earth seems to be calling it an extinction. They are not even sure what caused it- 252 million years ago is a long time. And using those convenient probability graphs that always tell us we won’t get hit by a comet or asteroid or supervolcanoes for a million years; what do they say about this event that rendered extinct 96 percent of marine vertebrate species and 70 percent of land vertebrate species?

    It can happen tomorrow and we would join the great silence.

  • Eniac April 3, 2013, 23:50

    If you actually look at that Wikipedia reference, you will notice a few things:

    1) None of the”events” shown in the plot has more extinction going on in its period than the two preceding periods combined. Not even the fearsome Permian-Triassic. You can make it sound drastic in your typical dramatic style, but on geological timescales, it isn’t really. Simpy because species go extinct all the time.

    2) It says there “the recovery of life on Earth took significantly longer than after any other extinction event,[4] possibly up to 10 million years.” I would call that “temporary”, in geological terms.

    3) It says “that the extinction was spread out over a few million years, with a very sharp peak in the last 1 million years of the Permian”. So, not exactly a single-day cataclysm. A gradual, but unusually persistent change in the environment that caused the gradual replacement of one set of species by another, better adapted one. Not likely caused by a one-time event such as an impact or a volcanic eruption. More likely a chemical change caused by life itself, similar to the first occurrence of free oxygen, which must have caused quite some extinction at its time.

    It can happen tomorrow and we would join the great silence.

    Very dramatic. As if you were sure that we would.

    In fact, our species has transcended the effect of the environment as no other ever has. We can live in the arctic and on the equator, in the desert and in the rainforest. We have a much better than 30% chance to be among those 30% surviving land vertebrate species after that million year “event”, I would think.

    Unless, of course, we do ourselves in first, by our own hands. But then, neither the Permian-Triassic nor meteor impact statistics are of much relevance. And a bit of global warming is NOT going to be sufficient for that, contemporary conventional wisdom notwithstanding.

  • GaryChurch April 4, 2013, 13:10

    “You can make it sound drastic in your typical dramatic style, but on geological timescales, it isn’t really. Simpy because species go extinct all the time.”

    Oh. It’s OK then.

    “Unless, of course, we do ourselves in first, by our own hands.”

    Doing nothing is included in that category of doing ourselves in. You might be happy with your risk assessment and accept we might have some hard times ahead but your view is that we will survive no matter what so it is appropriate to do….nothing.

    If you turn on the news one day and someone is talking about a plague or an impact then you can thank yourself for contributing to the coming catastrophe- by doing nothing.

  • Eniac April 5, 2013, 22:47

    … but your view is that we will survive no matter what so it is appropriate to do….nothing

    Far be that from me. How did you get that idea? Where did I say that? Anyway, let me clearly say it now: We need to do plenty of things, but it has to be the right ones, the ones that will actually work.

    Fantasies about importing solar energy from the moon and using decommissioned nuclear warheads to kick million ton spaceships like soccer balls are not it, I am sorry to say.

    Neither is building up imagined or actual but manageable threats into bogeymen that will distract from real dangers that are lurking.

  • Eniac April 5, 2013, 22:52

    The Dinosaurs did not find a way-

    In fact – they did. They got smaller and took to the air. Their descendants are all around us today, you can hear them singing every day.

  • ljk April 8, 2013, 13:57

    Eniac said on April 5, 2013 at 22:52:

    [GC] “The Dinosaurs did not find a way-”

    “In fact – they did. They got smaller and took to the air. Their descendants are all around us today, you can hear them singing every day.”

    Some of them also made their way to the Delta Quadrant. :^)

    On a more serious vein in this subject, I wonder why the dinosaurs did not have at least one branch which evolved into creating a technological civilization? They had 160 million years on Earth while humans have only been around for 7 million years and that last figure is being generous in terms of calling those distant ancestors human.

    This is one of many reasons why I want SETI to succeed: Are humans flukes? Do only mammals and similar species get to build cell phones and starships? Or have we just not funded enough archaeological expeditions?

  • Eniac April 9, 2013, 3:54

    The fact that we are the first on Earth to develop technology can NOT be construed as meaning it is a fluke. Like all major evolutionary innovations, the development of technological civilization is irreversible. This means it happens once, exactly. Therefore, there is no way we could not be the first. Therefore, no conclusions can be drawn from us being the first about whether the occurrence is likely or not.

    The irreversibility of the process and the vast amount of time available make technological civilization seem quite inevitable. Sooner or later it was going to happen. Had it happened sooner, we (or rather, the dinosaurs) would still be asking why it did not happen even sooner. The very question is absurd, in this light.

  • ljk April 25, 2013, 9:13

    News feature: 2013-146 April 24, 2013

    NASA Invites the Public to Fly Along with Voyager

    The full version of this story with accompanying images is at:

    http://www.jpl.nasa.gov/news/news.php?release=2013-146&cid=release_2013-146

    A gauge on the Voyager home page, http://voyager.jpl.nasa.gov, tracks levels of two of the three key signs scientists believe will appear when the spacecraft leave our solar neighborhood and enter interstellar space.

    When the three signs are verified, scientists will know that one of the Voyagers has hurtled beyond the magnetic bubble the sun blows around itself, which is known as the heliosphere.

    The gauge indicates the level of fast-moving charged particles, mainly protons, originating from far outside the heliosphere, and the level of slower-moving charged particles, also mainly protons, from inside the heliosphere. If the level of outside particles jumps dramatically and the level of inside particles drops precipitously, and these two levels hold steady, that means one of the spacecraft is closing in on the edge of interstellar space. These data are updated every six hours.

    Scientists then need only see a change in the direction of the magnetic field to confirm that the spacecraft has sailed beyond the breath of the solar wind and finally arrived into the vast cosmic ocean between stars. The direction of the magnetic field, however, requires periodic instrument calibrations and complicated analyses. These analyses typically take a few months to return after the charged particle data are received on Earth.

    Voyager 1, the most distant human-made spacecraft, appears to have reached this last region before interstellar space, which scientists have called “the magnetic highway.” Inside particles are zooming out and outside particles are zooming in. However, Voyager 1 has not yet seen a change in the direction of the magnetic field, so the consensus among the Voyager team is that it has not yet left the heliosphere.

    Voyager 2, the longest-operating spacecraft, but not as distant as Voyager 1, does not yet appear to have reached the magnetic highway, though it has recently seen some modest drops of the inside particle level.

    NASA’s Eyes on the Solar System program, a Web-based, video-game-like tool to journey with NASA’s spacecraft through the solar system, has added a Voyager module that takes viewers along for a ride with Voyager 1 as it explores the outer limits of the heliosphere. Time has been sped up to show one day per second. Rolls and other maneuvers are incorporated into the program, based on actual spacecraft navigation data. The charged particle data are also shown. Visit that module at: http://1.usa.gov/13uYqGP .

    The Voyager spacecraft were built and continue to be operated by NASA’s Jet Propulsion Laboratory, Pasadena, Calif. Caltech manages JPL for NASA. The Voyager missions are a part of NASA’s Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate at NASA Headquarters in Washington.

    For more information about the Voyager spacecraft, visit:

    http://www.nasa.gov/voyager and http://voyager.jpl.nasa.gov

    Jia-Rui C. Cook 818-354-0850
    Jet Propulsion Laboratory, Pasadena, Calif.
    jccook@jpl.nasa.gov

    2013-146

  • ljk May 26, 2013, 21:24

    Voyager: Outward bound

    Ed Stone has spent 36 years guiding the twin Voyager spacecraft through the Solar System. Next stop, interstellar space.

    Alexandra Witze

    22 May 2013 Corrected: 23 May 2013

    The 44 notebooks lined up neatly in Ed Stone’s office span just half a metre of shelf space. But inside these journals, in meticulous black printing, Stone has chronicled the longest journey that humans have ever launched.

    Since they left Earth in 1977, the twin Voyager spacecraft have conducted pioneering explorations of Jupiter, Saturn, Uranus and Neptune, revealing these gas giants and their moons to be far more active than scientists had expected. Now the two probes are cruising towards the edge of the Solar System — a boundary that has yet to be crossed by any emissary from Earth.

    Stone has chaperoned the Voyagers from their conception. He is the mission’s first and so far only project scientist, tasked with juggling the competing needs of the scientists who use the Voyagers’ instruments against those of the engineers that fly the craft. By all accounts, he has succeeded. “Somehow he got that discordant orchestra to play together,” says Andrew Ingersoll, a planetary scientist at the California Institute of Technology (Caltech) in Pasadena who was on the team as the spacecraft flew past Jupiter and Saturn.

    To many, the Voyagers are synonymous with the unflappable Stone. The man and the mission are bound together, even as the probes enter yet another phase in their storied lifetime. Almost 19 billion kilometres from Earth, Voyager 1 is flirting with the edge of interstellar space, the medium between the stars. Last July, it saw the flood of charged particles from the Sun subside to a mere trickle — a sign that the spacecraft may soon break out of the Solar System.

    Full article here:

    http://www.nature.com/news/voyager-outward-bound-1.13040

  • ljk June 27, 2013, 16:27

    http://www.jpl.nasa.gov/news/news.php?release=2013-209&cid=release_2013-209

    NASA’s Voyager 1 Explores Final Frontier of Our ‘Solar Bubble’

    June 27, 2013

    PASADENA, Calif. — Data from Voyager 1, now more than 11 billion miles (18 billion kilometers) from the sun, suggest the spacecraft is closer to becoming the first human-made object to reach interstellar space.

    Research using Voyager 1 data and published in the journal Science today provides new detail on the last region the spacecraft will cross before it leaves the heliosphere, or the bubble around our sun, and enters interstellar space. Three papers describe how Voyager 1’s entry into a region called the magnetic highway resulted in simultaneous observations of the highest rate so far of charged particles from outside heliosphere and the disappearance of charged particles from inside the heliosphere.

    Scientists have seen two of the three signs of interstellar arrival they expected to see: charged particles disappearing as they zoom out along the solar magnetic field, and cosmic rays from far outside zooming in. Scientists have not yet seen the third sign, an abrupt change in the direction of the magnetic field, which would indicate the presence of the interstellar magnetic field.

    “This strange, last region before interstellar space is coming into focus, thanks to Voyager 1, humankind’s most distant scout,” said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. “If you looked at the cosmic ray and energetic particle data in isolation, you might think Voyager had reached interstellar space, but the team feels Voyager 1 has not yet gotten there because we are still within the domain of the sun’s magnetic field.”

    Scientists do not know exactly how far Voyager 1 has to go to reach interstellar space. They estimate it could take several more months, or even years, to get there. The heliosphere extends at least 8 billion miles (13 billion kilometers) beyond all the planets in our solar system. It is dominated by the sun’s magnetic field and an ionized wind expanding outward from the sun. Outside the heliosphere, interstellar space is filled with matter from other stars and the magnetic field present in the nearby region of the Milky Way.

    Voyager 1 and its twin spacecraft, Voyager 2, were launched in 1977. They toured Jupiter, Saturn, Uranus and Neptune before embarking on their interstellar mission in 1990. They now aim to leave the heliosphere. Measuring the size of the heliosphere is part of the Voyagers’ mission.

    The Science papers focus on observations made from May to September 2012 by Voyager 1’s cosmic ray, low-energy charged particle and magnetometer instruments, with some additional charged particle data obtained through April of this year.

    Voyager 2 is about 9 billion miles (15 billion kilometers) from the sun and still inside the heliosphere. Voyager 1 was about 11 billion miles (18 billion kilometers) from the sun Aug. 25 when it reached the magnetic highway, also known as the depletion region, and a connection to interstellar space.

    This region allows charged particles to travel into and out of the heliosphere along a smooth magnetic field line, instead of bouncing around in all directions as if trapped on local roads. For the first time in this region, scientists could detect low-energy cosmic rays that originate from dying stars.

    “We saw a dramatic and rapid disappearance of the solar-originating particles. They decreased in intensity by more than 1,000 times, as if there was a huge vacuum pump at the entrance ramp onto the magnetic highway,” said Stamatios Krimigis, the low-energy charged particle instrument’s principal investigator at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “We have never witnessed such a decrease before, except when Voyager 1 exited the giant magnetosphere of Jupiter, some 34 years ago.”

    Other charged particle behavior observed by Voyager 1 also indicates the spacecraft still is in a region of transition to the interstellar medium. While crossing into the new region, the charged particles originating from the heliosphere that decreased most quickly were those shooting straightest along solar magnetic field lines. Particles moving perpendicular to the magnetic field did not decrease as quickly.

    However, cosmic rays moving along the field lines in the magnetic highway region were somewhat more populous than those moving perpendicular to the field. In interstellar space, the direction of the moving charged particles is not expected to matter.

    In the span of about 24 hours, the magnetic field originating from the sun also began piling up, like cars backed up on a freeway exit ramp. But scientists were able to quantify that the magnetic field barely changed direction — by no more than 2 degrees.

    “A day made such a difference in this region with the magnetic field suddenly doubling and becoming extraordinarily smooth,” said Leonard Burlaga, the lead author of one of the papers, and based at NASA’s Goddard Space Flight Center in Greenbelt, Md. “But since there was no significant change in the magnetic field direction, we’re still observing the field lines originating at the sun.”

    NASA’s Jet Propulsion Laboratory, in Pasadena, Calif., built and operates the Voyager spacecraft. California Institute of Technology in Pasadena manages JPL for NASA. The Voyager missions are a part of NASA’s Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate at NASA Headquarters in Washington.

    For more information about the Voyager spacecraft mission, visit:

    http://www.nasa.gov/voyager and http://voyager.jpl.nasa.gov

    Jia-Rui C. Cook 818-354-0850
    Jet Propulsion Laboratory, Pasadena, Calif.
    jccook@jpl.nasa.gov

    Steve Cole 202-358-0918
    NASA Headquarters, Washington
    stephen.e.cole@nasa.gov

    2013-209

  • ljk July 12, 2013, 20:57

    http://www.guardian.co.uk/science/2013/jul/09/nasa-voyager-solar-system-edge

    Voyager 1 spacecraft’s latest find takes the edge off the solar system

    Probe discovers transitional zone bordering interstellar space to bring another surprise for Nasa scientists

    Joel Achenbach for the Washington Post

    Guardian Weekly, Tuesday 9 July 2013 08.59 EDT

    Voyager 1 … ‘it changed the way we view our place in the cosmos’.

    Photograph: National Geographic Image Collec/Alamy

    The edge of the solar system has no edge, it turns out. It has a fuzzy transitional area, not quite solar system and not quite interstellar space.

    This basic fact of our star’s environment has been discovered by Voyager 1, one of the most remarkable spaceships ever built. Our premier scout of deep space, Voyager 1, is currently 11bn miles from the sun, beaming data to Earth as it scoots at 24,000kmph toward the constellation Ophiuchus.

    Scientists had assumed that Voyager 1, launched in 1977, would have exited the solar system by now. That would mean crossing the heliopause and leaving behind the vast bubble known as the heliosphere, which is characterised by particles flung by the sun and by a powerful magnetic field.

    The scientists’ assumption turned out to be half-right. On 25 August, Voyager 1 saw a sharp drop-off in the solar particles, also known as the solar wind. At the same time, there was a spike in galactic particles coming from all points of the compass. But the sun’s magnetic field still registers, somewhat diminished, on the spacecraft’s magnetometer. So it’s still in the sun’s magnetic embrace, in a sense.

    This unexpected transitional zone, dubbed the “heliosheath depletion region,” is described in three new papers about Voyager 1 published online last month by the journal Science.

    “There were some surprises,” said Ed Stone, who has been the lead scientist of Nasa’s Voyager program since 1972. “We expected that we would cross a boundary and leave all the solar stuff behind and be in all the interstellar stuff. It turned out, that’s not what happened.” So, how big is this transitional zone at the edge of the solar system?

    “No one knows,” said Stone, 77, a professor of physics at the California Institute of Technology and the former head of NASA’s Jet Propulsion Laboratory, Voyager’s home base. “It’s not in any of the models. We don’t know. It could take us a few more months, it could take us several more years to get through it.”

    The dimensions and nature of the heliosphere are not a wholly esoteric matter. The sun’s magnetic field deflects much of the radiation coming from other parts of the galaxy that was created in supernova explosions. Interstellar space is not a benign environment. The heliosphere’s features make life easier for blue planets such as Earth.

    Voyager 1 can be counted as one of the great exploratory craft in history, and none has gone farther, nor cruised steadily at such astonishing speed (a few have briefly gone faster while falling into the sun). Two Voyager probes were launched in 1977. Both spaceships carried a gold-plated record crammed with digital information about human civilization, including mathematical formulas, an image of a naked man and woman, whale vocalizations, and clips of classical and rock-and-roll music. (The famous joke was that the aliens listened to the record and replied, “Send more Chuck Berry.”)

    The two Voyagers embarked on what was called the Grand Tour, taking advantage of an orbital positioning of the four outer planets that happens less than once a century. Voyager 1 flew by Jupiter and Saturn before angling “north,” as astronomers would describe it. (There’s no up or down in space, but there is a north or south relative to the orbital plane of the planets.) Voyager 2 went past Jupiter and Saturn and flew by Uranus and Neptune before heading “south.”

    The images of those planets and their moons, now taken for granted, were stunning triumphs of the Voyager mission. And in 1990, Voyager 1, nearly 4 billion miles from the sun, turned its camera toward Earth and took an image of what Carl Sagan called the “pale blue dot” of our home planet.

    Now Voyager 1 is 124 astronomical units from the sun – one AU being roughly the mean distance from Earth to the sun, or about 150m kilometres. Voyager 2 is at 102 AU.

    These spacecraft are not immortal, even if sometimes they act like it. They have a power supply from the radioactive decay of plutonium-238, which generates heat. The half-life of that system is 88 years. Small thrusters occasionally are fired to keep Voyager 1’s 23-watt radio antenna pointed toward Earth, where the faint signals are picked up on huge arrays of radio telescopes in the United States, Spain and Australia. But Stone anticipates that weakening power will force scientists to start shutting down scientific instruments on Voyager 1 in 2020 and that by 2025, the last instrument will be turned off.

    “It changed the way we view our place in the cosmos,” said Bill Nye, the “Science Guy” who is chief executive of the Planetary Society in Pasadena, Calif. He said the new discovery by Voyager 1 is a classic example of why we explore: “What are you going to find over the unknown horizon? We don’t know. That why we explore out there.”

    NASA’s associate administrator for space technology, Michael Gazarik, said of Voyager 1’s durability: “It is amazing, especially in the harsh environment of space. This piece of hardware has a life of its own.”

    In 40,000 years, Voyager 1 will be closer to another star (with the romantic name AC+79 3888) than to the sun. And then what? It will just keep going – a silent, dark craft on a seemingly eternal journey.

    “It will be orbiting the center of the Milky Way galaxy essentially for billions of years, like all the stars,” said Stone of what has been, for him, the spacecraft of a lifetime.

    This article appeared in the Guardian Weekly, which incorporates material from the Washington Post

  • ljk September 20, 2013, 16:36

    NASA’s Plutonium Problem Could End Deep-Space Exploration

    BY DAVE MOSHER 09.19.136:30 AM

    In 1977, the Voyager 1 spacecraft left Earth on a five-year mission to explore Jupiter and Saturn. Thirty-six years later, the car-size probe is still exploring, still sending its findings home. It has now put more than 19 billion kilometers between itself and the sun. Last week NASA announced that Voyager 1 had become the first man-made object to reach interstellar space.

    The distance this craft has covered is almost incomprehensible. It’s so far away that it takes more than 17 hours for its signals to reach Earth. Along the way, Voyager 1 gave scientists their first close-up looks at Saturn, took the first images of Jupiter’s rings, discovered many of the moons circling those planets and revealed that Jupiter’s moon Io has active volcanoes.

    Now the spacecraft is discovering what the edge of the solar system is like, piercing the heliosheath where the last vestiges of the sun’s influence are felt and traversing the heliopause where cosmic currents overcome the solar wind. Voyager 1 is expected to keep working until 2025 when it will finally run out of power.

    None of this would be possible without the spacecraft’s three batteries filled with plutonium-238. In fact, Most of what humanity knows about the outer planets came back to Earth on plutonium power. Cassini’s ongoing exploration of Saturn, Galileo’s trip to Jupiter, Curiosity’s exploration of the surface of Mars, and the 2015 flyby of Pluto by the New Horizons spacecraft are all fueled by the stuff. The characteristics of this metal’s radioactive decay make it a super-fuel. More importantly, there is no other viable option. Solar power is too weak, chemical batteries don’t last, nuclear fission systems are too heavy. So, we depend on plutonium-238, a fuel largely acquired as by-product of making nuclear weapons.

    But there’s a problem: We’ve almost run out.

    “We’ve got enough to last to the end of this decade. That’s it,” said Steve Johnson, a nuclear chemist at Idaho National Laboratory. And it’s not just the U.S. reserves that are in jeopardy. The entire planet’s stores are nearly depleted.

    Full article here:

    http://www.wired.com/wiredscience/2013/09/plutonium-238-problem/