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The argument claiming that extraterrestrials don’t exist was actually proposed by the astronomer Michael Hart, in a paper he published in 1975. Hart supposed that if an extraterrestrial civilization arose in the galaxy it would develop interstellar travel and launch colonizing expeditions to nearby stars. These colonies would, in turn, launch their own starships spreading a wave of colonization across the galaxy. How long would the wave take to cross the galaxy? Assuming that the starships traveled at one tenth the speed of light and that no time was lost in building new ships upon arriving at the destination, the...

The Fermi Paradox By Tim Urban Facebook275k Twitter0 Google+0 Pinterest0 Everyone feels something when they’re in a really good starry place on a really good starry night and they look up and see this:Some people stick with the traditional, feeling struck by the epic beauty or blown away by the insane scale of the universe. Personally, I go for the old “existential meltdown followed by acting weird for the next half hour.” But everyone feels something.Physicist Enrico Fermi felt something too—”Where is everybody?”________________A really starry sky seems vast—but all we’re looking at is our very local neighborhood. On the very...

Enlarge Image Ray maker. The "Jellyfish nebula" (IC 443) and another supernova remnant gave researchers firm evidence that cosmic rays come from exploding stars. Credit: NASA/JPL-Caltech/UCLA For the past century, physicists have puzzled over cosmic rays, particles (mostly protons) that hurtle through space at high speed and seem to come from all directions equally. What's the source of these galactic projectiles? And how do they come to be traveling so fast? Today, an international team announced a major step toward answering those questions: conclusive evidence that at least some of the cosmic rays come from supernova remnants—expanding shells of...

The finding that fission releases huge amounts of energy launched a scientific and military race to understand and use this new atomic source of power Over Christmas vacation in 1938, physicists Lise Meitner and Otto Frisch received puzzling scientific news in a private letter from nuclear chemist Otto Hahn. When bombarding uranium with neutrons, Hahn had made some surprising observations that went against everything known at the time about the dense cores of atoms—their nuclei. Meitner and Frisch were able to provide an explanation for what he saw that would revolutionize the field of nuclear physics: A uranium nucleus could...

Explanation: If you could only see gamma-rays, photons with up to a billion or more times the energy of visible light, the Moon would be brighter than the Sun! That startling notion underlies this novel image of the Moon, based on data collected by the Fermi Gamma-ray Space Telescope's Large Area Telescope (LAT) instrument during its first seven years of operation (2008-2015). Fermi's gamma-ray vision doesn't distinguish details on the lunar surface, but a gamma-ray glow consistent with the Moon's size and position is clearly found at the center of the false color map. The brightest pixels correspond to the...

Two big ideas often come up in discussions about the search for extraterrestrial intelligence, or SETI. One is the Drake Equation, which estimates the number of civilizations in our Galaxy whose signals we might be able to detect--potentially thousands, according to plausible estimates. The other is the so-called Fermi paradox, which claims that we should see intelligent aliens here if they exist anywhere, because they would inevitably colonize the Galaxy by star travel--and since we don't see any obvious signs of aliens here, searching for their signals is pointless. The Drake Equation is perfectly genuine: it was created by astronomer...

Suddenly, space is getting interesting again. After decades of going boldly nowhere in low Earth orbit, Man, or rather his robotic emissaries, have made some startling discoveries in our Solar System. Cold, distant Pluto is – who would have thought it? – turning out to be one of the most interesting planets (yes, it is a planet) in the Solar System. Before the New Horizons probe turned up earlier this month, astronomers assumed it would be a dull, grey cratered rock. [SNIP] If we find life of any kind out there – whether it be Martian microbes (we have several...

During the walk to the Fuller Lodge, the physicists discussed a recent spate of UFO sightings, and a cartoon in the New Yorker Magazine depicting aliens and a flying saucer. Although the topic of conversation moved on as the group sat down for lunch, Edward Teller recalls “in the middle of the conversation, Fermi came out with the quite unexpected question ‘Where is everybody?’…The result of his question was general laughter because of the strange fact that in spite of Fermi’s question coming out of the clear blue, everybody around the table seemed to understand at once that he was...

This week marks the 70th anniversary of a turning point in human history. It was on December 2, 1942, that Enrico Fermi ordered the control rods pulled from the nuclear reactor he had built under the west stands of the University of Chicago’s Stagg Field stadium, thereby initiating the first artificial sustained-fission reaction in human history. A cryptic message flashed the electrifying news back to Washington. “The Italian navigator has landed in the new world.” The consequences of Fermi’s success were profound. Within two and a half years, the Manhattan Project advanced to build both uranium-isotope-separation and plutonium-manufacturing facilities on...

The story begins with a letter from Albert Einstein to Franklin D. Roosevelt in 1939. The celebrated physicist warned the president that Nazi Germany was developing the makings of an atomic bomb. Roosevelt knew what would happen if Hitler got such a weapon. The president ordered a massive secret project to make sure the U.S. beat him to it. Scientists from all over the country were enlisted in the effort. Early in 1942 Enrico Fermi and a team of physicists gathered at the University of Chicago's Metallurgical Laboratory. Their goal was to develop a self-sustaining nuclear pile. This was the...

"Fermi Bubbles, " which might appear as a void in visible light in spiral galaxies. is the term used by Richard Carrigan at the Fermi National Accelerator Laboratory in his work on the search for cosmic-scale artifacts like Dyson spheres or Kardashev civilizations. A Fermi bubble would grow as the civilization creating it colonized space, according to Carrigan... Searching for signatures of cosmic-scale archaeological artifacts such as Dyson spheres or Kardashev civilizations is an interesting alternative to conventional SETI. Uncovering such an artifact does not require the intentional transmission of a signal on the part of the original civilization... James...

Enrico Fermi’s paradox has occupied us more than occasionally in these pages, and for good reason. ‘Where are they,’ asked Fermi, acknowledging an obvious fact: Even if it takes one or two million years for a civilization to develop and use interstellar travel, that is but a blip in terms of the 13.7 billion year age of the universe. Von Neumann probes designed to study other stellar systems and reproduce, moving outward in an ever expanding wave of exploration, could easily have spread across the galaxy long before our ancestors thought of building the pyramids. Where are they indeed. Kelvin...

Thursday November 08 09:37 AM EST Fermi's Paradox II: What's Blocking Galactic Civilization? Or Are We Just Blind To It? By Seth ShostakAstronomer, Project Phoenix, SPACE.com    Could galactic empires exist? In a previous article, we noted that there has been plenty of time for aliens keen on colonizing the Milky Way to pull it off. However, we see no signs of galactic federation ("Star Trek" aside). Why does the cosmos look so untouched and unconquered? What is keeping advanced extraterrestrials from claiming every star system in sight? This puzzle, known as the Fermi Paradox, has burned up a lot ...

Fermi's Paradox Fermi's Paradox (i.e. Where are They?): The story goes that, one day back on the 1940's, a group of atomic scientists, including the famous Enrico Fermi, were sitting around talking, when the subject turned to extraterrestrial life. Fermi is supposed to have then asked, "So? Where is everybody?" What he meant was: If there are all these billions of planets in the universe that are capable of supporting life, and millions of intelligent species out there, then how come none has visited earth? This has come to be known as The Fermi Paradox. Fermi realized that any...

The error is the a priori assumption that UFOs cannot exist therefore no evidence to the contrary will be considered, never mind accepted. Few scientists would allow such faulty logic to prevail in their own field of expertise. Yet, in the emotionally laden field of UFOs, scientists let Condon stand uncorrected and disregarding pertinent facts has become the accepted norm... There are over 3000 cases reported by pilots, some of which include interference with flight controls. On numerous occasions air traffic controllers and other radar operators have noted unexplained objects on their scopes. So too have several astronomers and other...

The Fermi paradox—the estimation that extraterrestrial civilizations are common and would naturally expand into space, contradicting the lack of evidence that they exist anywhere—is the subject of fascinating speculation and guesswork. Every possible fate of extraterrestrial intelligence is proposed and explored. These thought experiments are not only interesting in their own right, but may help evaluate the state of a more terrestrial civilization. What will happen to humankind in the future? By examining the possible futures of extraterrestrial civilizations, we are simultaneously examining the possible futures of our own civilization. Put in another way, if an alien civilization somewhere had...

The failure of "Alexander," the newspaper wrote, has "brutally exposed the cultural and moral divide which slices America in two." Uh-huh. "It is being suggested that a film about a global warrior with dyed blond hair and waxed legs was never going to conquer an America fresh out of a presidential election in which gay rights became a major issue." Is there another America they might be talking about? Major issue? Brutally exposed? The last thing an American movie brutally exposed was Kathy Bates in the hot-tub scene of "About Schmidt."