Seth Shostak

Quote Topics Cited
A century ago, scientists believed there was only one obvious stomping ground for alien biology in our solar system: Mars. Because it was reminiscent of Earth, Mars was assumed to be chock-a-block with animate beings, and its putative inhabitants got a lot of column inches and screen time. Time
A factory that can turn carbon nanotubes into a sheet a yard wide and long enough to stretch one-fourth of the way to the moon is not something you'll find at your local industrial park. That's the show-stopper for the space elevator. The ribbon.
A practical way to travel between the stars is a must-have for space opera, and a sine qua non for our frequently vaunted future as a galactic society. Society ;Future ;Travel
About the only things that are unique to Earth are our biota and our culture. If aliens ever come here, they'd most likely be either biologists or music fans. Neither one has much reason to antagonize our armed forces. Music, Chants & Rapps
According to 'Star Trek' mythos, Starfleet Command - operational headquarters for a flotilla of craft that keep the cosmic peace - is located in San Francisco's Presidio, in the shadow of the Golden Gate Bridge (still carrying traffic, even in the 23rd century). War & Peace
Admittedly, it would take industrial-grade chutzpah and a massive dose of malevolence for anyone to bulldoze the spot where Neil Armstrong stepped off the Eagle lander. But even innocent visits could be damaging.
America's popular heroes have seldom been its great thinkers, and even less its scientists. The success of TV's 'Big Bang Theory,' which seems to give the lie to this claim, is more the exception that proves the rule. Success
Any beings advanced enough to traverse interstellar distances are at least a thousand years beyond our technical level. Spending gobs of time examining our missiles is equivalent to sending the Air Force back to the Middle Ages and insisting they examine the chain mail factories. Time
Any society that could come here could pick up the lights from New York. What should we do about that? Should we darken New York from now until the last human expires? Would we want to turn off all the radars at JFK airport? Society
Are two eyes, four appendages and an upright posture really essential for any creature that can ace the galactic SAT's? Maybe not. In fact, I'd venture that any aliens we ever detect or (less likely) encounter will look quite different than this self-referential stereotype.
Are we the only members of the Galaxy that can actually understand what a galaxy is? Could Homo sapiens really be the pinnacle of Creation - the cleverest critters in the cosmos? If we learn the answer is 'no,' that would affect our philosophies forever.
As far as I can tell, the only unambiguous consequence of the claimed invasion of Earth by beings from another star system has been a nonstop torrent of TV specials. So if you're one of the many who believe the aliens are here, you really do have to admit this: They're the best houseguests ever.
Astronomers still can't decide what the shape of our universe is. Is it closed and finite, which is to say, is there a countable tally of all the galaxies that exist, even beyond the ones we can see? Or is it infinite? The latter possibility is still on the table.
'Battleship' is not a film that Francois Truffaut would have made. Nor would any of those other namby-pamby European directors. Nope, this picture eschews that Continental obsession with small stories, set in quaint towns filled with pockmarked folk doing their banal things.
Buying insurance is no one's idea of fun. And it's especially easy to berate something as funky-sounding as writing checks to defend our neighborhoods against apartment-size rocks from space. But this is one insurance pitch that makes perfect sense. Ask the dinos.
By 2020, most home computers will have the computing power of a human brain. That doesn't mean that they are brains, but it means that in terms of raw processing, they can process bits as fast as a brain can. So the question is, how far behind that is the development of a machine that's as smart as we are? Power ;Science, Mathematics, Engineering & Technology
Certainly the history of astronomy shows that every time we thought we were special, we were wrong. Time ;History
Charles Darwin sailed around the world for two years on the 'Beagle,' and he had quite a bit of interest in things like the iguanas of the Galapagos, even though they were primitive compared to your average Englishman.
Clearly, enriching the cosmos with heavy elements takes a while. So there's inevitably an interval between the sterile aftermath of the Big Bang and a time when the cosmic chemistry set had enough ingredients to make rocky planets (and squishy biology). Time
Clearly, unless thinking beings inevitably wipe themselves out soon after developing technology, extraterrestrial intelligence could often be millions or billions of years in advance of us. We're the galaxy's noodling newbies. Science, Mathematics, Engineering & Technology
Consider that the overwhelming majority of those 40,000 near-Earth asteroids are small enough to fit on the parking lot at the mall. And while these rocky runts won't cause Armageddon, they could still flatten such popular hominid hangouts as Manhattan or downtown Des Moines.
Consider: Life arose on Earth close to four billion years ago. Four billion years of slithering, swimming, and soaring life forms. But only in the last 200 thousand years has a species arisen that can fathom the laws of nature and build hardware able to signal its presence. Life ;Nature
Consider: The human genome consists of about 3.3 billion base pairs. Since there are only four types of pair, that amounts to 0.8 gigabytes of information, or about what you can fit on a CD. With a microwave radio transmitter, you could beam that amount of information into space in a few minutes, and have it travel to anyone at light speed. Travel
Data from orbiting telescopes like NASA's Kepler Mission hint that the tally of habitable planets in our galaxy is many billion. If E.T.'s not out there, then Earth is more than merely special - it's some sort of miracle.
'Dating Game' wasn't social commentary, political analysis, Shakespearean-level drama or even blunt-force comedy. It was just the televised equivalent of meeting someone at a bar. But it appealed to our most basic Darwinian instinct: selecting a good mate. You can't go wrong when a show's premise is hard-wired into human DNA.
Despite tantalizing suggestions of fossilized microbes in meteorites, puzzling and possibly biogenic methane gas in the martian atmosphere, and a long-standing controversy over the Viking lander experiments of nearly 40 years ago, there's still no Exhibit A that points unequivocally to biology in our own back yard.
Despite the impression you may have from watching too much TV, movies are not about reproducing reality. They're about telling stories. Arts, Culture, Entertainment & Lifestyle
Diminutive worlds are more likely to be rocky, and lapped by oceans and atmospheres. In the vernacular of 'Star Trek,' these would be M-class planets: life-friendly oases where biology could begin and bumpy-faced Klingons might exist.
Disasters happen. We still have no way to eliminate earthquakes, wildfires, hurricanes, floods or droughts. We cope as best we can by fortifying ourselves against danger with building codes and levees, and by setting aside money to clean up afterwards. Money, Coins & Minting
'E.T.' was far-fetched. 'E.T.' was this wimpy-looking kid that came to Earth to pick some plants, but he came from the Andromeda Galaxy to do that.
Each year, thousands of UFOs are sighted and reported, which is an impressive tally of unidentified aerial phenomena. Surveys show that roughly one-third of the populace believes that at least some of this sky show is due to extraterrestrial spacecraft, here to probe our airspace and, when that proves boring, our bodies.
Engineers are now experimenting with 4,096-line TV systems, suggesting that with the next generation of sets you'll be able to count the grass blades on the Superbowl field, an obvious lifestyle improvement.
Estimates are that at least 70 per cent of all stars are accompanied by planets, and since the latter can occur in systems rather than as individuals (think of our own solar system), the number of planets in the Milky Way galaxy is of order one trillion.
'Eternal inflation,' as it's called - the endless generation of new universes - may be a hyper-cosmic imperative. It seems that it must happen.
Even if the Moon didn't exist - even if it had been vaporized billions of years ago by cantankerous Klingons - there would still be (somewhat lower) tides raised by the Sun. For creatures dependent on the oceans' ebb and flow, life could go on. Life
Ever since the infamous quiz show scandals of the 1950s, the feds had insisted that TV game shows be honest - or that at least they didn't cheat. So as a 'Dating Game' bachelor, I didn't know what I was going to be asked. The other bachelors and I were required to concoct our answers in real time. Time
Ever since the Second World War, television signals (as well as FM radio and radar) have served as Homo sapiens' emissaries into deep space. High-frequency, high-power broadcasts have filled an Earth-centered bubble more than 60 light-years in radius with signals. War & Peace
Every day, the temperature of Sol's surface increases by five billionths of a degree, a change of no consequence for thousands of millennia to come. But a few hundred million years from now, barring a fix by our descendants, this relentless heating will substantially change Earth's biosphere in ways that might not be survivable for us.
Everything you see is filtered through your visual system (imperfect) and your brain (also imperfect, despite what your mom told you). Witness testimony is the worst kind of evidence in science. Science, Mathematics, Engineering & Technology
Exploration is an oft-lauded human activity, and one that resonates in the same way that music and good stories do. It's hard-wired into our species (and into many others), no doubt because it has survival value. Exploration occasionally rewards those who accept its risks, usually with new resources. Music, Chants & Rapps
Explorers tend to be the aggressive types - why else would they risk scurvy, mutiny and other bad things to go out there? So, you could say that any aliens that are actually moving and interested in going somewhere are likely to be more aggressive. But who knows?
Faith is a personal matter, and should never be a cudgel to stifle inquiry. We tried that approach about 1,200 years ago. The experiment was called the Dark Ages. Religion & God
Five centuries ago, Copernicus upset humanity's applecart with the news that the Earth is not the center of the cosmos. It could be that, before you've paid off your house, we'll learn that the universe is not the center of the universe, either!
Five centuries from now - barring unimaginable catastrophe - the moon will be developed real estate. There's economic incentive to exploit the moon - the helium-3 will be useful in powering fusion reactors, and the rare earth elements could supplant the limited terrestrial supply of these materials.
Forecasting Armageddon has become trendy of late, with a great deal of attention being given to an interpretation of the Mayan Calendar suggesting that Mother Earth is destined for doom in December of 2012.
Frankly, I'll believe in horoscopes the day I can describe my personality to an astrologer and they tell me what date I was born.
Give consideration to the fact that alien astronomers could have scrutinized Earth for more than 4 billion years without detecting any radio signals, despite the fact that our world is the poster child for habitability.
Given the tendency of many to picture God's realm as somewhere high above Earth - an idea that sounds suspiciously like the Greek stories of deities perched on inaccessible mountain tops - it may seem plausible to assume that astronomers have special insight. Well, of course they don't. Religion & God
Heads are a good deal, and I think they would be a common feature. It's hard to think of species that don't have heads, although there are some. It's good to have a head because it puts some of the sensory organs - eyes, ears, whiskers or whatever - next to the CPU, the brain.
Here's a news flash: scientists can be wrong. That's no big deal (unless the scientist is you), since research is self-correcting. Consequently, most errors by scientists become historical curiosities, with little long-term importance.
Hollywood usually guesses that extraterrestrials would only be interested in one of three things: (1) They want to breed with us, because their own reproductive machinery is on the blink; (2) They want Earth's resources; or (3) They want the Earth. All of it.
Humans have existed only for the last 0.001 percent of cosmic time. All of which says that - unless the Homo sapiens brain is the one-and-only instance of cogitating machinery - nearly all the intelligence that's out there is beyond our level. And that intelligence is more than just a little bit beyond. Time
I actually think the chances that we'll find E.T. are pretty good.
I got interested in astronomy at the age of 8 because I was looking at an atlas of the planets in my parents' apartment in Arlington, where I grew up. I got a telescope at age 10, which is pretty normal, and by the time I was in eighth grade, I had already seen a lot of cheesy sci-fi films. Time
I still remember my dismay in the summer of 2007 when - for the first time in the history of planet Earth - America's share of auto production dropped below 50 percent. Time ;History
I studied Latin in high school, and I was reading stuff from Cicero. And that signal took a few thousand years to get to me. But I was still interested in what he had to say.
I think a lot of kids are interested in two science subjects: dinosaurs and aliens. The reason is almost genetic; we're hard-wired to be interested in things that might be a little dangerous. Science, Mathematics, Engineering & Technology
I think there's a lot of intelligence out there, but that's just my guess. Question is: Are they peaceable or hostile? You could say that the peaceable ones are just going to stay at home and play with their Nintendos, so if you do meet any of them, they might be hostile.
I you look at the drawings of aliens made by people who believe that Earth is under saucer attack, you'll quickly note that most of these invaders fit the Tinseltown mold. But you have to admit: the grays are highly anthropomorphic.
If aliens are really hanging out in our 'hood, it's hard to imagine any other fact more worthy of study. If not, then why does such a large fraction of the populace insist on believing they're here?
If gravity were somewhat stronger or weaker, stars wouldn't exist, and neither would you. And the same can be said of other constants of physics. Several have to be 'just right.'
If the cosmos isn't finite, then far, far away, floating duplicates of your brain - with all its experiences, thoughts, and emotions - are occasionally (and temporarily) thrown together by the random combining of atoms. Such 'Boltzmann brains,' as they're called, are a disturbing consequence of an unlimited universe.
If this is the only planet on which not only life, but intelligent life, has arisen, that would be very unusual. Life
If you could drive straight down, into a tunnel bored through the crust of the planet, you'd hit this molten mess in about an hour. It's called the asthenosphere - a sluggish sea, several hundred miles thick, on which floats the Earth's cool epidermis - the so-called tectonic plates.
Imagine if the dinosaurs had tried picturing the rulers of their planet 100 million years hence. They'd undoubtedly envision these creatures as... dinosaurs! Conceiving of aliens as polished versions of ourselves is appealing, but unconvincing.
In 1908, there was a persuasive demonstration of the power of high-speed, low-mass asteroids in rural Siberia. The Tunguska impactor iced millions of pine trees and about a zillion mosquitoes - and was no larger than an office building. Power
In a movie, it's often important to have aliens whose gestures and facial expressions can be 'read' by humans. And in the days before sophisticated computer animation, most extraterrestrial bit players were guys in rubber suits. Such practical considerations forced Hollywood's hand when it came to aliens - they look like us for good reasons.
In archaeology, context is the basis of many discoveries that are imputed to the deliberate workings of intelligence. If I find a rock chipped in such a way as to give it a sharp edge, and the discovery is made in a cave, I am seduced into ascribing this to tool use by distant, fetid and furry ancestors.
In days gone by, scientists would speak solemnly about our solar system's 'habitable zone' - a theoretical region extending from Venus to Mars, but perhaps not encompassing either, where a planet would be the right temperature to have liquid water on its surface.
In general, when moviemakers talk to scientists, they usually see them as a resource to solve particular technical problems or script problems for them. So, something like: what sort of weaponry would aliens be able to wield?
In the 19th century, if you had a basement lab, you could make major scientific discoveries in your own home. Right? Because there was all this science just lying around waiting for somebody to pick it up. Science, Mathematics, Engineering & Technology
In the four years since its launch, Kepler has chalked up 122 new and confirmed planets. It's also caught the scent of nearly three thousand additional objects, of which probably 80 percent or more will turn out to be other-worldly orbs.
Is E.T. out there? Well, I work at the SETI Institute. That's almost my name. SETI: Search for Extraterrestrial Intelligence. In other words, I look for aliens, and when I tell people that at a cocktail party, they usually look at me with a mildly incredulous look on their face. I try to keep my own face somewhat dispassionate. Work, Workers & The Labor Force
It bears mentioning that the Milky Way is only one of 150 billion galaxies visible to our telescopes - and each of these will have its own complement of planets.
It seems obvious that if a species has the brainpower for speech, along with the sort of appendages that can manipulate a pair of pliers, it will eventually blunder into science, technology, and radio. Science, Mathematics, Engineering & Technology
It seems that 'rocket scientist' is a job category that's here for the long haul, like 'mortician.' But all this activity masks an important point: rockets are not a terribly efficient way to lift things into space.
It will be the mother of all telescopes, and you can bet it will do for astronomy what genome sequencing is doing for biology. The clumsy, if utilitarian, name of this mirrored monster is Large Synoptic Survey Telescope, or LSST. You can't use it yet, but a peak in the Chilean Andes has been decapitated to provide a level spot for placement.
It's always a tough call deciding whether, as a scientist, you should argue publicly with the creationists. It's a dilemma that I encounter frequently in another subject area: Does it make sense to bandy words with someone from the UFO community?
It's easy to reckon that the oomph to hurl even a Smart Car-size spacecraft to another star at, say, 20 percent the speed of light (and land it when it arrives) is the energy contained in 50 billion gallons of gasoline. The tank's not big enough.
It's hard to imagine anything more interesting than learning how we're woven into the enormous tapestry of existence. Where did our universe come from? How special is our world, and how special are we? We allocate tens of billions of dollars annually to NASA, NSF and academia in search of the answers. Education, Learning, Knowledge & Training
It's hardly a secret that I'm skeptical of declarations that the aliens are out and about on our planet. Still, I try to answer every one of these mails and phone calls because, after all, it's not a violation of physics to travel from one star system to another. Travel
It's the default premise in science: If you observe something in nature only once, you assume that what you've seen is typical. That's because 'typical' is just another way of saying 'most probable.' Nature ;Science, Mathematics, Engineering & Technology
It's worth noting that invoking God as the entity who set our universe in motion isn't contradicted by the data. Of course, scientists would say the supreme being hypothesis is faith, and outside the realm of science - that it's not amenable to experiment. But we currently have the same problem with the notion of parallel universes. Religion & God ;Science, Mathematics, Engineering & Technology
I've often fantasized about visiting the Bahamian beach where Columbus first stumbled ashore in 1492. Sadly, no one knows where that beach is. In fact, no one's even sure which island Columbus first encountered (there are three candidates). It's a pity, a disappointment, and a lost revenue source for the Bahamians.
Judging by informal observation, most young Americans burn up their spare time buffing their emotional IQ and self-esteem with social media and non-stop texting. That's great for eye-thumb coordination, but what about the satisfaction of actually making something? Time
Junk, redundancy, and inefficiency characterize astrophysical signals. It seems they characterize cells and sea lions, too. These biological constructions have lots of superfluous and redundant parts, and are a long way from being optimally built or operated.
Jupiter, a world far larger than Earth, is so warm that it currently radiates more internal heat than it receives from the Sun.
Just knowing that there's somebody else out there - that what's happened on this planet has also happened in many other places - that might change our lives in a very subtle way, but it's interesting to know and worth looking for.
Lamentably, alien audiences may be frustrated by the switch to digital television. That's because the transmitter power for DTV is fairly evenly spread across the spectrum. The spikiness is gone, and from afar, the attention-grabbing squeals of analog television's carriers have been replaced by DTV's smooth, low hiss. Power
Like prospecting in the 19th century, reconnaissance of the asteroids would of necessity take place in an arena where trouble is likely and help is distant. Heroic stories of individual triumph and failure, set on landscapes never seen by humankind, are in the cards. Failure
Look, science is hard, it has a reputation of being hard, and the facts are, it is hard, and that's the result of 400 years of science, right? I mean, in the 18th century, in the 18th century you could become an expert on any field of science in an afternoon by going to a library, if you could find the library, right? Science, Mathematics, Engineering & Technology
Many people suggest using mathematics to talk to the aliens, and Dutch computer scientist Alexander Ollongren has developed an entire language (Lincos) based on this idea. But my personal opinion is that mathematics may be a hard way to describe ideas like love or democracy. Love, Romance, Marriage & Sex
Mars still remains the astrobiology community's number one choice for 'nearest rock with life,' but there are many researchers who argue that the moons of Jupiter are better bets. In particular, Europa, Ganymede, and Callisto are all thought to hide vast oceans of liquid water beneath their icy, outer skins. Life
Mining asteroids is a well-oiled trope of science-fiction. But someday, actually doing it will make economic sense. Many of the essential metals of our society, such as platinum, copper and zinc, are rapidly becoming scarce. The asteroids might offer a replacement supply, providing the materials our descendants will need for a high quality life. Society ;Life
Most of the intelligence out there must be artificial intelligence. We keep looking for critters like us living on a planet like ours, where in fact the majority of the intelligence out there is not biological. That would be my argument.
Most of the things at the zoo don't look like us. We're one design that works. Our chimp pals sort of look like us, so that's a different take on the same basic design. But fish don't look like us, and giraffes don't. They look a little like us, but not too much. And insects certainly don't look like us, and they work just fine. Work, Workers & The Labor Force
Mountains aren't eternal: even the most imposing massifs are smoothed away by weathering in a few hundred million years or less. Plate tectonics makes new ones, and without it, our future would be flat. Future
NASA's Office of Commercial Exploration has been concerned about protecting the landing zones where humans first walked on the Moon, and one of my colleagues, ecologist Margaret Race, has been part of their deliberations.
Neil Armstrong was no Christopher Columbus. In most respects, he was better. Unlike the famous fifteenth century seafarer, Armstrong knew where he landed. He also spent his time in public service, not in jail, and his passing was marked by world-wide encomiums. He ended his days as a celebrated explorer rather than a royal inconvenience. Time ;Fame
Note to academics: Aristarchus' track record of astronomical research would probably have guaranteed him tenure somewhere, if tenure had been invented. His stack of reprints included measuring the distances of the Moon and Sun.
Of course there is still unexplored terrestrial territory, but most of it is waterlogged. Submersed secret places, such as the Challenger Deep, which today lure hi-tech adventurers like Richard Branson and James Cameron, will undoubtedly provide welcome fodder for 'National Geographic.'
Of course, Sol is a big ball of hot gas, but one that - thanks to its endlessly boiling innards - shakes and vibrates. By studying patterns on the Sun's surface, astronomers can learn much about Sol's internal construction.
On Mars, where the air is spare - a hundred times less dense than on Earth - someone could hear you scream. But you'd have to really strain to get anyone's attention. On the Red Planet, where the wind is high-pitched and faint, even a symphony orchestra will sound as thin as cheap gruel.
Once typecast as the indispensable altarpiece of a well-appointed living room, TVs have infected every human environment. The average American household has more television sets than people.
One of the jovian moons, Europa, is coated with twice as much liquid water as is sloshing around our planet.
Our brains are continuing to evolve, and perhaps a few tens of thousands of years from now, our descendants will walk around with five pound brains, allowing them insights that we can't imagine.
Our computers double in capability on time scales of only a few years. It's hardly outrageous to believe that we will successfully develop thinking machines within a handful of decades, or at most a century or two. If that happens, these artificial sentients will quickly leave us behind. Time ;Science, Mathematics, Engineering & Technology
Our retinas and brains have been wired by a hundred million years of evolution to find outlines in a visually complex landscape. This helps us to recognize prey and predators.
People don't learn science in movies. You don't go to the movies thinking, 'I hope I learn some quantum mechanics this afternoon.' But on the other hand, movies are instrumental and influential in getting young people interested in science. Hope ;Science, Mathematics, Engineering & Technology ;Arts, Culture, Entertainment & Lifestyle
Planets that don't currently sport plate tectonics, such as Venus and Mars, are scarcely habitable. Tectonics might be a requirement of any world that aspires to a rich diversity of life. Life ;Sports & Athletics
Plate tectonics is not all havoc and destruction. The slow movement of continents and ocean floors recycles carbon dioxide dissolved in the oceans back into the atmosphere. Without this slow speed carbon cycle, Earth's temperatures would cool dozens of degrees below your comfort zone.
Recent results from astronomers who study the occasional gravitational lensing of unknown worlds by intervening stars suggest that orphan planets could be at least as numerous as the stars. In other words, there could be hundreds of billions of orphan worlds shuffling through our galaxy.
Scientists - who prefer explanations subject to laboratory tests - figure that everything we see today was as inevitable as wrinkles, once the Big Bang established physics. Stars and planets were cooked up as huge clouds of matter collapsed and coalesced.
Sending greeting cards to aliens is hardly a new idea. In 2005, Craigslist solicited messages for broadcast to space by a transmitter in Florida, and in 2008, NASA beamed a Beatles song to the North Star (Polaris), on the assumption that any putative Polarians would appreciate the Fab Four's 1960s-genre compositions.
Since the Renaissance, a concept called 'progress' has been baked into our society. Progress - founded on an accumulation of knowledge through experience (and in the case of science, through experiment). To build on the past rather than endlessly relive it. That's what separates us from the beasts. Education, Learning, Knowledge & Training
Some pundits have proposed that the aliens have come here to breed with us. Apparently, too much bike riding or something similar has rendered them incapable of reproducing within their own species. But do extraterrestrial infants toddle through your neighborhood?
Star Trek's genial premise is that the cosmos is flush with intelligent species, and our descendants will interact with them face-to-face, thanks to warp drive and some winsome space cadets.
Studying Sol's interior by looking for analogous patterns on its incandescent face is known as helioseismology, an active - if largely unpronounceable - research area that uses sound as a probe of our home star.
Sure, nobody will make a fortune if we figure out why the Big Bang happened. But just about everyone would like to know.
Sure, our three-pound brains might be inadequate to understand the universe. But perhaps they're just good enough to build something that can.
Television is ephemeral, a fact that some will find reassuring. But earthlings will continue to pump the kilowatts into the ether. And eventually, when those signals have washed over a few hundred thousand star systems, someone may notice.
Thanks to the fact that the Earth isn't a perfect sphere, and invoking a bunch of Newtonian physics, you can deduce that our planet wobbles, too, taking roughly 26,000 years to trace out a small circle on the sky, a phenomenon known as precession.
The bottom line is that finding orphan planets - small, faint, and located who-knows-where - is not for the faint of heart. The task is comparable to observing a match flame at the distance of Pluto. The WISE satellite, a hi-tech, space-based infrared telescope especially suited for such work, has found only a few. Work, Workers & The Labor Force
The bottom line is that the position of the Sun relative to the stars slowly changes for any given date, and over the course of 26,000 years, it can easily slide between constellations. So you may think you're a Pisces, but you're actually an Aquarius.
The bottom line is, like, one in five stars has at least one planet where life might spring up. That's a fantastically large percentage. That means in our galaxy, there's on the order of tens of billions of Earth-like worlds. Life
The central region of the Milky Way, known as the bulge, is stuffed with literally tens of billions of stars. And most of these are old - considerably older than our Sun or its neighbors - because this part of the galaxy formed first. Consequently, bulge stars are generally deficient in heavy elements.
The cosmos is three times as old as Earth. During most of creation's 14 billion year history, our solar system wasn't around. Nonetheless, the early universe still had the right stuff for life, and contained worlds that were just as suitable for spawning biology and intelligence as our own. Life ;History
The Earth has been lawned with life for something over 3.5 billion years. That's a span of time great enough to encompass some honest-to-goodness catastrophe. For example, 700 million years ago, Earth underwent a planet-wide deep freeze, with ice covering the oceans from the poles to the equator. Life ;Time
The era during which only governments could put hardware on the Moon is coming to an end. There are 26 private teams competing for the $30 million Google Lunar X-Prize - to be awarded for sending a robotic spacecraft to this nearby world that can roam at least 500 meters, and send back data such as a photo.
The fact that we can't easily foresee clues that would betray an intelligence a million millennia farther down the road suggests that we're like ants trying to discover humans. Ask yourself: Would ants ever recognize houses, cars, or fire hydrants as the work of advanced biology? Work, Workers & The Labor Force
The idea of close encounters of the zero'th kind - which is to say, not a close encounter at all, but simply uncovering evidence that someone's out there - dates back to the Victorian era.
The ideas of science germinate in a matrix of established knowledge gained by experiment; they are not lonesome thoughts, born in a rarified realm where no researcher has ever gone before. Education, Learning, Knowledge & Training ;Science, Mathematics, Engineering & Technology
The limitless content of our universe might be only one instance of a large (and possibly infinite) number of other universes.
The longtime standard for American TV was 525 lines from top to bottom of the image. As a practical matter, that was roughly equivalent to 350 thousand pixels - pretty crude, given that photos made with your iPhone boast five million pixels.
The majority of my UFO diet consists of reports describing suspected encounters. This is not surprising, as there are thousands of sightings annually. The emailer has seen something unusual in the sky that he interprets as probable evidence of alien presence.
The math is dead simple: it seems that the frequency of planets able to support life is roughly one percent. In other words, a billion or more such worlds exist in our galaxy alone. That's a lot of acreage, and it takes industrial-strength credulity to believe it's all bleakly barren. Life
The mission of NASA's Kepler telescope is to lift the scales from our eyes and reveal to us just how typical our home world is. Kepler operates by measuring the dimming of stars as planets pass ('transit') in front of them. It has found thousands of previously unknown worlds.
The Moon is a ball of left-over debris from a cosmic collision that took place more than four billion years ago. A Mars-sized asteroid - one of the countless planetesimals that were frantically churning our solar system into existence - hit the infant Earth, bequeathing it a very large natural satellite.
The Moon stabilizes Earth's obliquity. Well, almost. The tilt actually varies between 22 and 24.5 degrees - and the variation is enough to induce such environmental inconveniences as the occasional ice age. Without the Moon, it might be much worse.
The most attractive habitats for synthetic sentience might be the vicinities of exceptional sources of energy - for example black holes, or even the neighbourhoods of large stars, which routinely boil off the energy of ten thousand suns. These are the destinations they may seek.
The next time you check your moves in the mirror and reflect on how special you are, consider that somewhere in this universe or in another parallel universe, your double might be doing the same. This would be the ultimate Copernican Revolution. Not only are we not special, we could be infinitely ordinary. Time
The overwhelming bulk of the cosmos is deathly quiet. But here and there - on worlds where matter is thick and conditions are right - noises are commonplace. And in some cases, these noisy worlds may ring with the sounds of life - the bleats and bellows of creatures we have never seen, but may someday discover. Life
The planets and moons of our solar system are blatantly visible because they reflect sunlight. Without the nearby Sun, these planets would be cryptic and dark on the sky.
The principal reason for the universe's poker face is that its constituents are far away. Stars careen through space, and galaxies spin at speeds thousands of times faster than a jet plane. But given their distance, you'd need the patience of Job to notice much change in their appearance or position. Patience
The space elevator's not just another competitive technology, promoted by people who simply like the idea of diminishing the luster of the thrusters. It would open wide the doors to space. Science, Mathematics, Engineering & Technology
The split between religion and science is relatively new. Isaac Newton, who first worked out the laws by which gravity held the planets and even the stars in their traces, was sufficiently impressed by the scale and regularity of the universe to ascribe it all to God. Religion & God ;Science, Mathematics, Engineering & Technology
The stars look the same from night to night. Nebulae and galaxies are dully immutable, maintaining the same overall appearance for thousands or millions of years. Indeed, only the sun, moon and planets - together with the occasional comet, asteroid or meteor - seem dynamic.
The strongest signals leaking off our planet are radar transmissions, not television or radio. The most powerful radars, such as the one mounted on the Arecibo telescope (used to study the ionosphere and map asteroids) could be detected with a similarly sized antenna at a distance of nearly 1,000 light-years.
The thing to keep in mind is that we're still in the very early days when it comes to the search for extraterrestrial intelligence. Saying there's a silence is a bit like if Columbus, looking to discover a new continent, only sailed 10 miles off the coast of Spain before turning back to say, 'Nothing out there!'
The total funding of SETI (the Search for Extraterrestrial Intelligence) in the U.S. is 0.0003 percent of the tax monies spent on health and human services. And it's not even tax money. The SETI Institute's hunt for signals is funded by donations. Health, Healthcare & Medicine ;Money, Coins & Minting
The total number of people that do a job that has the same description as mine in the entire world is fewer than 10. There's a lot of effort looking for life in space - that's a lot of what NASA does, but they're not necessarily looking for the kind of life that can hold up its side of a conversation. Life
The usual metric for whether a planet is habitable or not is to ascertain whether liquid water could exist on its surface. Most worlds will either be too cold, too hot or of a type (like Jupiter) that may have no solid surface and be swaddled in noxious gases.
There will be an end point to how good TV pictures can get. The boob tube has hugely benefited from the rapid advance of digital electronics. Consequently, the strategy for hardware has changed. In the old days, sets had to be as simple as Elmer Fudd to keep them inexpensive. All the technical 'smarts' were at the transmitter end.
There's no doubt that the Moon is more than a handy night light and a hair restorer for werewolves. It's responsible for the substantial amplitude of earthly ocean tides. These are of obvious influence if you're a geoduck, a type of clam that people dig up at low tide.
This plucky NASA telescope is able to find planets en masse. If you compare planet hunting to prospecting for gold, then Kepler is equivalent to trading in your trusty pan for a diesel-powered sluice box.
Three-fourths of the universe is hydrogen, and oxygen is incredibly abundant, too. So H2O is something you can find nearly everywhere.
Today's voguish threats, including climate change, population growth, massive war, and resource depletion, are all amenable to a fix if we act prudently. And even if we don't, these problems are incapable of obliterating all of humanity, let alone destroying the Earth. No, the real End of Days will happen slowly, as the Sun ages. War & Peace
Typically, only about 2 percent of the American populace tunes in to PBS's 'Nova' series - the most successful science show on the tube. 'Survivor' and 'X Factor' get twice the ratings. Science, Mathematics, Engineering & Technology
Very few societies on Earth developed science as we know it today. On the other hand, the number is not zero - the Greeks, the Chinese, and the Maya did, among others. Once invented, science proved so useful that it spread like mold on a petri dish. Science, Mathematics, Engineering & Technology
Virtually any pointed edifice is considered a candidate for alien engineering. After all, how could the Egyptians or Mayans have possibly stacked up stone blocks into pyramids?
We can never prove that we're alone in the universe. But the Allen Telescope Array could prove that we're not.
We can no better imagine what will be happening on the moon 500 years from now than Columbus could imagine contemporary Manhattan. Except to say that it will be a place familiar to billions of people.
We haven't yet found a speck of evidence for biology on another world, so we have no objective way to judge whether life is a onetime fluke or a near-inevitable phenomenon. Life
We'll be 'outsourcing' our creativity and our thought processes to manufactured components that could be inconspicuously implanted beneath our coiffeurs. Welcome to the Borg. You might not be entirely comfortable with such cybernetic enhancements, but all the smart money says it's going to happen. Money, Coins & Minting
We're interested in things that have big teeth, and you can see the evolutionary value of that, and you can also see the practical consequences by watching 'Animal Planet.' You notice they make very few programs about gerbils. It's mostly about things that have big teeth.
We're not just any star stuff, most of which is humdrum hydrogen and listless helium. Our bodies include fancier ingredients like carbon, oxygen, nitrogen, phosphorous, and a few other herbs and spices.
We've accounted for 95 percent of all the stars in the Milky Way. The other 5 percent are big, bright stars - the kind that dominate the night sky, but are lamentably both rare and short-lived. If biology's your thing, you can forget those guys.
'What was there before the Big Bang?' That's a question that both kids and adults love to pose to anyone who seems sympathetic. After all, if the universe has only been around for roughly 14 billion years, isn't it legitimate to ask what was in existence before the mother-of-all-events cranked up the cosmos? Love, Romance, Marriage & Sex
What's a space elevator? Simply described, it's a thin ribbon, about 3 feet wide and 60 thousand miles long, stretching upwards from the surface of the Earth. The lower end is bolted to a heavy anchor (think of an oil drilling platform), and the top is capped with a counterweight.
When I graduated high school, nearly a half-million people subscribed to 'Popular Electronics' magazine. Soldering up some radio or hi-fi amplifier on the basement workbench was not just a personal passion - a lot of young people were doing the same. The magazine expired in 1999 for lack of interest.
When I was a kid, which was just after Edison invented moving pictures, there were films that involved aliens coming to Earth for bad purposes.
When it comes to brains, size matters. It's not all that matters, of course. Whales and dolphins have brains that are larger than humans', but few of the flippered and fluked set win tenure at Stanford. Our brains are the largest in proportion to body size, and they're also highly sophisticated.
When was the last time you bought an American-made radio or television? If you're Gen X or younger, the answer is 'never.' Does the label on that shirt or skirt you're wearing say 'Made in the U.S.A.'? If so, you probably got it at Goodwill, or maybe at a Smithsonian garage sale. Time
While human space travel is daunting, machines - with their indefinitely long lifetimes - could travel the galaxy. It might make little difference to them that bridging the distance from one star to the next could take hundreds of thousands of years or more. Travel
While I have always thought that the motivation for looking for E.T. was both self-evident and patently worthy, it's possible that I'm a victim of my own job description. Others don't inevitably agree. Some will opine that there are better ways to spend the money. Money, Coins & Minting
While it may be disappointing, I have to confess to people who ask for my insights on the meaning of it all that astronomy doesn't provide any clearly useful data on matters of sin and souls.
You may not see massive UFO exhibits at your local science museum, but there's no dearth of saucer stories infesting my email. Every day, I receive several reports of alien sightings, extraterrestrial plans for Earth, and agitated screeds about the reluctance of scientists to take the whole subject seriously. Science, Mathematics, Engineering & Technology