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Perry Gerakines and his colleagues in the Cosmic Ice Lab at NASA's Goddard Space Flight Center in Greenbelt are working on something very simple – ice – but in a truly extraordinary way. Gerakines not just making regular ice or snow flakes, but a microscopically thin cosmic ice, which requires intense cold and extremely low pressure, to create. His creation is unique and can reproduce some of the most critical chemical reactions in space thereby allowing us to learn on how life first began.
Reggie Hudson, head of the Cosmic Ice Lab remarks that this is not high school chemistry, but bitter cold chemistry in extreme conditions of pressure and exposure to intense radiation. Researchers world-wide have been given this exclusive opportunity to study the ‘mega cool’ formation of cosmic ice using a particle accelerator that could mimic the cosmic radiation that drives such reactions. This offers valuable information on the chemistry of ice under the surface of moons and planets alike.
The recipe created by Gerakines involves pumping out air to a level that is a billion times lower than normal for our planet, chilled to 433 degree Fahrenheit. During this phase, molecules are altered instantly from their gaseous state into the rebellious solid called “amorphous ice”. These crystals are widespread in interstellar space, especially in comets and icy moons.
Gerakines spikes this amorphous ice with amino acids (glycine, alanine or phenylalanine), the main ingredients for life on Earth and finally bombards the ice with radiation energy using a proton beam. It is clear that the OH group generated acts as a radiation shield, absorbing tons of proton energy. Surprisingly, the acids last longer at higher temperatures. This conclusion clearly supports the view that amino acids could last longer at extreme radiation and depth.
Dozens of extraterrestrial civilizations likely exist in the universe, scientists say
June 15 (UPI) -- In a newly published paper, scientists have offered a narrower estimate range for the number of possible extraterrestrial civilizations lurking within our home galaxy.
Using the assumption that life evolves on alien planets similar to how it emerged on Earth, researchers determined there should be roughly 30 active communicating intelligent civilizations inside the Milky Way, according to a study published Monday in the Astrophysical Journal.
"There should be at least a few dozen active civilizations in our Galaxy under the assumption that it takes 5 billion years for intelligent life to form on other planets, as on Earth," lead researcher Christopher Conselice, professor of astrophysics at the University of Nottingham, said in a news release. "The idea is looking at evolution, but on a cosmic scale. We call this calculation the Astrobiological Copernican Limit."
To make a more precise estimate about the number of alien civilizations in the Milky Way, researchers relied on both a weak and hard limit. The weak limit is the time it takes for the evolution of intelligent civilizations, less than or approximately 5 billion years. Humans capable of long-distance communication emerged roughly 4.5 billion years after life began.
The hard limit is the metal content in sun-like stars. For a solar system to host intelligent life, scientists estimate the star must feature metal content equal to that of the sun.
"The classic method for estimating the number of intelligent civilizations relies on making guesses of values relating to life, whereby opinions about such matters vary quite substantially," said first author Tom Westby, a Nottingham astrophysicist. "Our new study simplifies these assumptions using new data, giving us a solid estimate of the number of civilizations in our galaxy."
As scientists acknowledged in their paper, there are other challenges -- besides the Astrobiological Copernican Limits -- facing intelligent civilizations and our ability to communicate with them.
In order for humans on Earth to make contact with an alien civilization, the faraway civilization must enjoy staying power. Humans have been capable of long-distance communication for roughly 100 years. If civilizations appear but don't last as long as humans -- if they blink in and out of existence -- we may never connect with them.
In order to communicate with one of the galaxy's intelligent civilizations, both humans and aliens need advanced communications technologies. According to the latest analysis, the average alien civilization would be 17,000 light-years away, complicating the sending and receiving of communication signals.
"Our new research suggests that searches for extraterrestrial intelligent civilizations not only reveals the existence of how life forms, but also gives us clues for how long our own civilization will last," Conselice said.
"If we find that intelligent life is common then this would reveal that our civilization could exist for much longer than a few hundred years, alternatively if we find that there are no active civilizations in our Galaxy it is a bad sign for our own long-term existence," he said. "By searching for extraterrestrial intelligent life -- even if we find nothing -- we are discovering our own future and fate."
Advanced Cosmic Ice Research Reveals Information About How Life Began - History
by Holli Riebeek· design by Robert Simmon· December 19, 2005
Richard Alley might have envied paleoceanographer Jerry McManus’ warm, ship-board lab. (See previous installment: “A Record from the Deep.”) One of the researchers in the Greenland Ice Sheet Project 2 (GISP2), Alley huddled in a narrow lab cut into the Greenland Ice Sheet, where “the temperature stayed at a ‘comfortable’ twenty below [Fahrenheit],” he wrote in his book about his research, The Two-Mile Time Machine. An assembly line of science equipment lined the twenty-foot-deep trench that served as a makeshift lab. For six weeks every summer between 1989 and 1993, Alley and other scientists pushed columns of ice along the science assembly line, labeling and analyzing the snow for information about past climate, then packaging it to be sent for further analysis and cold storage at the National Ice Core Laboratory in Denver, Colorado. Nearby, a specially built drill bored into the thick ice sheet twenty-four hours a day under the perpetual Arctic sun. Essentially a sharpened pipe rotating on a long, loose cable, the drill pulled up cores of ice from which Alley and others would glean climate information.
Throughout each year, layers of snow fall over the ice sheets in Greenland and Antarctica. Each layer of snow is different in chemistry and texture, summer snow differing from winter snow. Summer brings 24 hours of sunlight to the polar regions, and the top layer of the snow changes in texture—not melting exactly, but changing enough to be different from the snow it covers. The season turns cold and dark again, and more snow falls, forming the next layers of snow. Each layer gives scientists a treasure trove of information about the climate each year. Like marine sediment cores, an ice core provides a vertical timeline of past climates stored in ice sheets and mountain glaciers.
Ice sheets contain a record of hundreds of thousands of years of past climate, trapped in the ancient snow. Scientists recover this climate history by drilling cores in the ice, some of them over 3,500 meters (11,000 feet) deep. These photographs show experimental drilling on the Greenland Ice Cap in summer 2005. (Photographs copyright Reto Stöckli, NASA GSFC)
The seasonal snow layers are easiest to see in snow pits, writes Alley, the Evan Pugh Professor in the Environment Institute and Department of Geosciences at Pennsylvania State University. To see the layers, scientists dig two pits separated by a thin wall of snow. One pit is covered, and the other is left open to sunlight. By standing in the covered pit, scientists can study the annual snow layers in the snow wall as the sunlight filters through the other side. “I have stood in snow pits with dozens of people—drillers, journalists, and others—and so far, every visitor has been impressed. The snow is blue, something like the blue seen by deep sea divers, an indescribable, almost achingly beautiful blue,” writes Alley. “The next thing most people notice is the layering.”
Blue light filtered through the wall of an Antarctic snow pit illuminates "Tuck," the mascot for Tuckahoe Elementary School in Henrico County, Virginia. The furry white owl accompanied scientists to Antarctica as part of an educational program. In the wall of the pit, dark and light bands of slowly compacted snow distinguish snow deposited in the winter from snow deposited in the summer. (Photograph courtesy Christopher Shuman, NASA GSFC)
To pry climate clues out of the ice, scientists began to drill long cores out of the ice sheets in Greenland and Antarctica in the late 1960s. By the time Alley and the GISP2 project finished in the early 1990s, they had pulled a nearly 2-mile-long core (3,053.44 meters) from the Greenland ice sheet, providing a record of at least the past 110,000 years. Even older records going back about 750,000 years have come out of Antarctica. Scientists have also taken cores from thick mountain glaciers in places such as the Andes Mountains in Peru and Bolivia, Mount Kilimanjaro in Tanzania, and the Himalayas in Asia.
The gradually increasing weight of overlying layers compresses deeply buried snow into ice, but annual bands remain. Relatively young and shallow snow becomes packed into coarse and granular crystals called firn (top: 53 meters deep). Older and deeper snow is compacted further (middle: 1,836 meters). At the bottom of a core (lower: 3,050 meters), rocks, sand, and silt discolor the ice. (Photographs courtesy U.S. National Ice Core Laboratory)
The ice cores can provide an annual record of temperature, precipitation, atmospheric composition, volcanic activity, and wind patterns. In a general sense, the thickness of each annual layer tells how much snow accumulated at that location during the year. Differences in cores taken from the same area can reveal local wind patterns by showing where the snow drifted. More importantly, the make-up of the snow itself can tell scientists about past temperatures. As with marine fossils, the ratio of oxygen isotopes in the snow reveals temperature, though in this case, the ratio tells how cold the air was at the time the snow fell. In snow, colder temperatures result in higher concentrations of light oxygen. (See The Oxygen Balance.)
Researchers retrieve climate records from mountain glaciers in addition to the records from polar ice sheets. Drilling sites around the world help distinguish trends in local climate from trends in global climate. This drilling station is located at an elevation of 6,425 meters (21,080 feet) on the summit of Nevado Coropuna in the Peruvian Andes. (Photograph copyright Jason Box, Ohio State University/Byrd Polar Research Center)
Scientists can confirm these chemistry-based temperature measurements by observing the temperature of the ice sheet directly. The ice sheet’s thickness makes its temperature much more resistant to change than the six inches of snow that might fall on your driveway during a winter snowstorm. As Alley explained to the Earth Observatory, the ice sheet can be compared to a frozen roast that is put directly into the oven. The outside heats up quickly, but the center remains cold, close to the temperature of the freezer, for a long time. Similarly, the ice sheet has warmed somewhat since the Ice Age, but not completely. The top has warmed as global temperatures have warmed, while the bottom has been warmed by heat flow from deep inside the Earth. But in the middle of an ice sheet, the ice remains close to the Ice Age temperatures at which it formed. “Because we understand how heat moves in ice, [and] we know how cold the ice is today, we can calculate how cold the ice was during the Ice Age,” says Alley.
The ice core recovered from Vostok, Antarctica, records over 400,000 years of climate history. This interactive graph shows temperature measurements derived from the core. Temperatures equal to or greater than the recent average (gray line) delineate interglacial periods, while colder temperatures indicate ice ages.
Scroll the graph in time by dragging the slider on the miniature graph (lower). Zoom in and out on the data with the plus and minus buttons (lower left). [Interactive designed by Kristin Henry, (Galaxy Goo) and Robert Simmon (NASA GSFC)]
When scientists lower an ultra-precise thermometer into a hole in the ice, they can detect the temperature variations that have occurred since the Ice Age. The near-surface ice temperature, like the atmosphere today, is warm, and then the temperature drops in the layers formed roughly between AD 1450 and 1850, a period known as the Little Ice Age, one of several cold snaps that briefly interrupted the overall warming trend ongoing since the end of the Ice Age. As the thermometer goes deeper into the ice sheet, the temperature warms again, and then plummets to the temperatures indicative of the Ice Age. Finally, the bottom layers of the ice sheet are warmed by heat coming from the Earth. These directly measured temperatures represent a rough average—a record of trends, not variable, daily temperatures—but climatologists can compare the thermometer temperatures with the oxygen isotope record as a way to calibrate those results.
Scientists measure the temperature of an ice sheet directly by lowering a thermometer into the borehole that was drilled to retrieve the ice core. Like an insulated thermos, snow and ice preserve the temperature of each successive layer of snow, which reflects general atmospheric temperatures when the layer accumulated. Close to the surface of the bedrock, the lowest layers of the ice are warmed by the heat of the Earth. These physical temperature measurements help calibrate the temperature record scientists obtain from oxygen isotopes. (Graph based on data provided by Gary Clow, United States Geological Survey)
As valuable as the temperature record may be, the real treasure buried in the ice is a record of the atmosphere’s characteristics. When snow forms, it crystallizes around tiny particles in the atmosphere, which fall to the ground with the snow. The type and amount of trapped particles, such as dust, volcanic ash, smoke, or pollen, tell scientists about the climate and environmental conditions when the snow formed. As the snow settles on the ice, air fills the space between the ice crystals. When the snow gets packed down by subsequent layers, the space between the crystals is eventually sealed off, trapping a small sample of the atmosphere in newly formed ice. These bubbles tell scientists what gases were in the atmosphere, and based on the bubble’s location in the ice core, what the climate was at the time it was sealed. Records of methane levels, for example, indicate how much of the Earth wetlands covered because the abundance of life in wetlands gives rise to anaerobic bacteria that release methane as they decompose organic material. Scientists can also use the ice cores to correlate the concentration of carbon dioxide in the atmosphere with climate change—a measurement that has emphasized the role of carbon dioxide in global warming. (see “Explaining the Evidence.”)
Finally, anything that settles on the ice tends to remain fixed in the layer it landed on. Of particular interest are wind-blown dust and volcanic ash. As with dust found in sea sediments, dust in ice can be analyzed chemically to find out where it came from. The amount and location of dust tells scientists about wind patterns and strength at the time the particles were deposited. Volcanic ash can also indicate wind patterns. Additionally, volcanoes pump sulfates into the atmosphere, and these tiny particles also end up in the ice cores. This evidence is important because volcanic activity can contribute to climate change, and the ash layers can often be dated to help calibrate the timeline in the layers of ice.
Air bubbles trapped in the ice cores provide a record of past atmospheric composition. Ice core records prove that current levels of carbon dioxide and methane, both important greenhouse gases, are higher than any previous level in the past 400,000 years. (Photograph courtesy U.S. National Ice Core Laboratory)
Though ice cores have proven to be one of the most valuable climate records to date, they only provide direct evidence about temperature and rainfall where ice still exists, though they hint at global conditions. Marine sediment cores cover a broader area—nearly 70 percent of the Earth is covered in oceans—but they only give tiny hints about the climate over the land. Soil and rocks on the Earth’s surface reveal the advance and retreat of glaciers over the land surface, and fossilized pollen traces out rough boundaries of where the climate conditions were right for different species of plants and trees to live. Unique water and rock formations in caves harbor a climate record of their own. To understand the Earth’s climate history, scientists must bring together all of these scattered threads into a single, seamless story.
- Alley, R., 2000: The Two-Mile Time Machine, Princeton University Press, Princeton, New Jersey.
- Bradley, R., 1999: Paleoclimatology, Academic Press, Harcourt Brace and Company, San Diego, California.
- Imbrie, J. and K. P. Imbrie, 1979: Ice Ages, Enslow Publishers: Hillside, New Jersey.
- The Ice Core Record
Ash from volcanic eruptions becomes trapped in ice sheets along with snow and dust. Scientists use the volcanic ash found in ice cores to date the cores and to estimate the intensity of past volcanic activity. This satellite image shows black ash from the eruption of Hekla on top of bright white Icelandic snow on February 29, 2000. (NASA image courtesy Jesse Allen)
The Greenland ice cores & global warming temperatures
In the 1990’s, scientists began the immense task of drilling into the summit of the Greenland ice sheet. The meticulous extraction of pure ice cores were used to measure the history of earth’s climate change. The samples were extracted two miles deep, far away from ice flow that distorted previous data.
These pure ice core readings revealed a remarkable image of prehistoric climate change. Of interest, was the temperature change as from the last ice age, known as the Younger Dryas period.
When data from 11, 600 years ago was compared to present day readings it revealed regular patterns of temperature oscillation. The natural variation is an increase and decrease of 2-4 degrees Celsius every few decades.
One big feature the study revealed was that in the past 250,000 years, the last 11,600 have been the longest prolonged period of relatively stable climate.
Evidence of climate change over the past 10,000 years.
As the graph oscillates backward and forwards, we can see a pattern of cooling and warming through time. As the line moves to the right, temperatures are warming, and as it moves left, temperatures are cooling.
These fluctuations represent changes of a few degrees Celsius and which are part of earth’s natural cycle. As the line approaches the bottom of the graph, there is a slight cooling trend. The following graph then reveals the period is abruptly interrupted by the end of the Younger Dryas period.
So Where Are They?
If the Copernican principle is applied to life, then biology may be rather common among planets. Taken to its logical limit, the Copernican principle also suggests that intelligent life like us might be common. Intelligence like ours has some very special properties, including an ability to make progress through the application of technology. Organic life around other (older) stars may have started a billion years earlier than we did on Earth, so they may have had a lot more time to develop advanced technology such as sending information, probes, or even life-forms between stars.
Faced with such a prospect, physicist Enrico Fermi asked a question several decades ago that is now called the Fermi paradox: where are they? If life and intelligence are common and have such tremendous capacity for growth, why is there not a network of galactic civilizations whose presence extends even into a “latecomer” planetary system like ours?
Several solutions have been suggested to the Fermi paradox. Perhaps life is common but intelligence (or at least technological civilization) is rare. Perhaps such a network will come about in the future but has not yet had the time to develop. Maybe there are invisible streams of data flowing past us all the time that we are not advanced enough or sensitive enough to detect. Maybe advanced species make it a practice not to interfere with immature, developing consciousness such as our own. Or perhaps civilizations that reach a certain level of technology then self-destruct, meaning there are no other civilizations now existing in our Galaxy. We do not yet know whether any advanced life is out there and, if it is, why we are not aware of it. Still, you might want to keep these issues in mind as you read the rest of this chapter.
Is there a network of galactic civilizations beyond our solar system? If so, why can’t we see them? Explore the possibilities in the cartoon video “The Fermi Paradox—Where Are All the Aliens?”
Key concepts and summary
Life on Earth is based on the presence of a key unit known as an organic molecule, a molecule that contains carbon, especially complex hydrocarbons. Our solar system formed about 5 billion years ago from a cloud of gas and dust enriched by several generations of heavier element production in stars. Life is made up of chemical combinations of these elements made by stars. The Copernican principle, which suggests that there is nothing special about our place in the universe, implies that if life could develop on Earth, it should be able to develop in other places as well. The Fermi paradox asks why, if life is common, more advanced life-forms have not contacted us.
organic molecule: a combination of carbon and other atoms—primarily hydrogen, oxygen, nitrogen, phosphorus, and sulfur—some of which serve as the basis for our biochemistry
HEALING WITH ANIMALS Islamic medicine had some roots in folk remedies that used animals’ organs. Many manuscripts drew on these traditions, such as Book on the Usefulness of Animals by the 14th-century Syrian scholar Ibn al-Durayhim. Avicenna also wrote of the use of birds’ wings, pigeon’s blood, and donkey’s liver as cures for certain maladies.
“The viper is skinned and dried [to become] a hair-removal paste. If its ashes are mixed with vinegar and smeared on erysipelas [a skin infection] they cure it, and hemorrhoids too.”
Snake miniature, 14th century edition, from Marvels of Creation, by al-Qazwini
The History of Space Exploration
During the time that has passed since the launching of the first artificial satellite in 1957, astronauts have traveled to the moon, probes have explored the solar system, and instruments in space have discovered thousands of planets around other stars.
Earth Science, Astronomy, Social Studies, U.S. History, World History
Apollo 11 Astronauts on Moon
A less belligerent, but no less competitive, part of the Cold War between the Soviet Union and the United States was the space race. The Soviet Union bested its rival at nearly every turn, until the United States beat them to the finish line by landing astronauts on the moon. Neil Armstrong and Buzz Aldrin completed that mission in 1969.
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We human beings have been venturing into space since October 4, 1957, when the Union of Soviet Socialist Republics (U.S.S.R.) launched Sputnik, the first artificial satellite to orbit Earth. This happened during the period of political hostility between the Soviet Union and the United States known as the Cold War. For several years, the two superpowers had been competing to develop missiles, called intercontinental ballistic missiles (ICBMs), to carry nuclear weapons between continents. In the U.S.S.R., the rocket designer Sergei Korolev had developed the first ICBM, a rocket called the R7, which would begin the space race.
This competition came to a head with the launch of Sputnik. Carried atop an R7 rocket, the Sputnik satellite was able to send out beeps from a radio transmitter. After reaching space, Sputnik orbited Earth once every 96 minutes. The radio beeps could be detected on the ground as the satellite passed overhead, so people all around the world knew that it was really in orbit. Realizing that the U.S.S.R. had capabilities that exceeded U.S. technologies that could endanger Americans, the United States grew worried. Then, a month later, on November 3, 1957, the Soviets achieved an even more impressive space venture. This was Sputnik II, a satellite that carried a living creature, a dog named Laika.
Prior to the launch of Sputnik, the United States had been working on its own capability to launch a satellite. The United States made two failed attempts to launch a satellite into space before succeeding with a rocket that carried a satellite called Explorer on January 31, 1958. The team that achieved this first U.S. satellite launch consisted largely of German rocket engineers who had once developed ballistic missiles for Nazi Germany. Working for the U.S. Army at the Redstone Arsenal in Huntsville, Alabama, the German rocket engineers were led by Wernher von Braun and had developed the German V2 rocket into a more powerful rocket, called the Jupiter C, or Juno. Explorer carried several instruments into space for conducting science experiments. One instrument was a Geiger counter for detecting cosmic rays. This was for an experiment operated by researcher James Van Allen, which, together with measurements from later satellites, proved the existence of what are now called the Van Allen radiation belts around Earth.
In 1958, space exploration activities in the United States were consolidated into a new government agency, the National Aeronautics and Space Administration (NASA). When it began operations in October of 1958, NASA absorbed what had been called the National Advisory Committee for Aeronautics (NACA), and several other research and military facilities, including the Army Ballistic Missile Agency (the Redstone Arsenal) in Huntsville.
The first human in space was the Soviet cosmonaut Yuri Gagarin, who made one orbit around Earth on April 12, 1961, on a flight that lasted 108 minutes. A little more than three weeks later, NASA launched astronaut Alan Shepard into space, not on an orbital flight, but on a suborbital trajectory&mdasha flight that goes into space but does not go all the way around Earth. Shepard&rsquos suborbital flight lasted just over 15 minutes. Three weeks later, on May 25, President John F. Kennedy challenged the United States to an ambitious goal, declaring: &ldquoI believe that this nation should commit itself to achieving the goal, before the decade is out, of landing a man on the moon and returning him safely to Earth."
In addition to launching the first artificial satellite, the first dog in space, and the first human in space, the Soviet Union achieved other space milestones ahead of the United States. These milestones included Luna 2, which became the first human-made object to hit the Moon in 1959. Soon after that, the U.S.S.R. launched Luna 3. Less than four months after Gagarin&rsquos flight in 1961, a second Soviet human mission orbited a cosmonaut around Earth for a full day. The U.S.S.R. also achieved the first spacewalk and launched the Vostok 6 mission, which made Valentina Tereshkova the first woman to travel to space.
During the 1960s, NASA made progress toward President Kennedy&rsquos goal of landing a human on the moon with a program called Project Gemini, in which astronauts tested technology needed for future flights to the moon, and tested their own ability to endure many days in spaceflight. Project Gemini was followed by Project Apollo, which took astronauts into orbit around the moon and to the lunar surface between 1968 and 1972. In 1969, on Apollo 11, the United States sent the first astronauts to the Moon, and Neil Armstrong became the first human to set foot on its surface. During the landed missions, astronauts collected samples of rocks and lunar dust that scientists still study to learn about the moon. During the 1960s and 1970s, NASA also launched a series of space probes called Mariner, which studied Venus, Mars, and Mercury.
Space stations marked the next phase of space exploration. The first space station in Earth orbit was the Soviet Salyut 1 station, which was launched in 1971. This was followed by NASA&rsquos Skylab space station, the first orbital laboratory in which astronauts and scientists studied Earth and the effects of spaceflight on the human body. During the 1970s, NASA also carried out Project Viking in which two probes landed on Mars, took numerous photographs, examined the chemistry of the Martian surface environment, and tested the Martian dirt (called regolith) for the presence of microorganisms.
Since the Apollo lunar program ended in 1972, human space exploration has been limited to low-Earth orbit, where many countries participate and conduct research on the International Space Station. However, unpiloted probes have traveled throughout our solar system. In recent years, probes have made a range of discoveries, including that a moon of Jupiter, called Europa, and a moon of Saturn, called Enceladus, have oceans under their surface ice that scientists think may harbor life. Meanwhile, instruments in space, such as the Kepler Space Telescope, and instruments on the ground have discovered thousands of exoplanets, planets orbiting other stars. This era of exoplanet discovery began in 1995, and advanced technology now allows instruments in space to characterize the atmospheres of some of these exoplanets.
A less belligerent, but no less competitive, part of the Cold War between the Soviet Union and the United States was the space race. The Soviet Union bested its rival at nearly every turn, until the United States beat them to the finish line by landing astronauts on the moon. Neil Armstrong and Buzz Aldrin completed that mission in 1969.
Discovery of the cosmic background
Beginning in 1948, the American cosmologist George Gamow and his coworkers, Ralph Alpher and Robert Herman, investigated the idea that the chemical elements might have been synthesized by thermonuclear reactions that took place in a primeval fireball. According to their calculations, the high temperature associated with the early universe would have given rise to a thermal radiation field, which has a unique distribution of intensity with wavelength (known as Planck’s radiation law), that is a function only of the temperature. As the universe expanded, the temperature would have dropped, each photon being redshifted by the cosmological expansion to longer wavelength, as the American physicist Richard C. Tolman had already shown in 1934. By the present epoch the radiation temperature would have dropped to very low values, about 5 kelvins above absolute zero (0 kelvin [K], or −273 °C [−460 °F]) according to the estimates of Alpher and Herman.
Interest in these calculations waned among most astronomers when it became apparent that the lion’s share of the synthesis of elements heavier than helium must have occurred inside stars rather than in a hot big bang. In the early 1960s physicists at Princeton University, New Jersey, as well as in the Soviet Union, took up the problem again and began to build a microwave receiver that might detect, in the words of the Belgian cleric and cosmologist Georges Lemaître, “the vanished brilliance of the origin of the worlds.”
The actual discovery of the relict radiation from the primeval fireball, however, occurred by accident. In experiments conducted in connection with the first Telstar communication satellite, two scientists, Arno Penzias and Robert Wilson, of the Bell Telephone Laboratories, Holmdel, New Jersey, measured excess radio noise that seemed to come from the sky in a completely isotropic fashion (that is, the radio noise was the same in every direction). When they consulted Bernard Burke of the Massachusetts Institute of Technology, Cambridge, about the problem, Burke realized that Penzias and Wilson had most likely found the cosmic background radiation that Robert H. Dicke, P.J.E. Peebles, and their colleagues at Princeton were planning to search for. Put in touch with one another, the two groups published simultaneously in 1965 papers detailing the prediction and discovery of a universal thermal radiation field with a temperature of about 3 K.
Precise measurements made by the Cosmic Background Explorer (COBE) satellite launched in 1989 determined the spectrum to be exactly characteristic of a blackbody at 2.735 K. The velocity of the satellite about Earth, Earth about the Sun, the Sun about the Galaxy, and the Galaxy through the universe actually makes the temperature seem slightly hotter (by about one part in 1,000) in the direction of motion rather than away from it. The magnitude of this effect—the so-called dipole anisotropy—allows astronomers to determine that the Local Group (the group of galaxies containing the Milky Way Galaxy) is moving at a speed of about 600 km per second (km/s 400 miles per second [miles/s]) in a direction that is 45° from the direction of the Virgo cluster of galaxies. Such motion is not measured relative to the galaxies themselves (the Virgo galaxies have an average velocity of recession of about 1,000 km/s [600 miles/s] with respect to the Milky Way system) but relative to a local frame of reference in which the cosmic microwave background radiation would appear as a perfect Planck spectrum with a single radiation temperature.
The COBE satellite carried instrumentation aboard that allowed it to measure small fluctuations in intensity of the background radiation that would be the beginning of structure (i.e., galaxies and clusters of galaxies) in the universe. The satellite transmitted an intensity pattern in angular projection at a wavelength of 0.57 cm after the subtraction of a uniform background at a temperature of 2.735 K. Bright regions at the upper right and dark regions at the lower left showed the dipole asymmetry. A bright strip across the middle represented excess thermal emission from the Milky Way. To obtain the fluctuations on smaller angular scales, it was necessary to subtract both the dipole and the galactic contributions. An image was obtained showing the final product after the subtraction. Patches of light and dark represented temperature fluctuations that amount to about one part in 100,000—not much higher than the accuracy of the measurements. Nevertheless, the statistics of the distribution of angular fluctuations appeared different from random noise, and so the members of the COBE investigative team found the first evidence for the departure from exact isotropy that theoretical cosmologists long predicted must be there in order for galaxies and clusters of galaxies to condense from an otherwise structureless universe. These fluctuations correspond to distance scales on the order of 10 9 light-years across (still larger than the largest material structures seen in the universe, such as the enormous grouping of galaxies dubbed the “Great Wall”).
The Wilkinson Microwave Anisotropy Probe (WMAP) was launched in 2001 to observe the fluctuations seen by COBE in greater detail and with more sensitivity. The conditions at the beginning of the universe left their imprint on the size of the fluctuations. WMAP’s accurate measurements showed that the early universe was 63 percent dark matter, 15 percent photons, 12 percent atoms, and 10 percent neutrinos. Today the universe is 72.6 percent dark energy, 22.8 percent dark matter, and 4.6 percent atoms. Although neutrinos are now a negligible component of the universe, they form their own cosmic background, which was discovered by WMAP. WMAP also showed that the first stars in the universe formed half a billion years after the big bang.
July 2020: 'Save the Children' and the Wayfair conspiracy theory
In the summer of 2020, the movement pivoted its pro-Trump narrative to focus on "Save the Children," a movement that purports to seek an end to human trafficking. Actual anti-human-trafficking advocacy groups have begged QAnon believers to stop clogging their hotlines with false tips.
But with both anti-mask and anti-human-trafficking rhetoric, QAnon gained steam among "normies," in what University of Amsterdam researchers have called the "normiefication" of QAnon.
A conspiracy theory alleging the Wayfair furniture company was selling human children on its website went viral in mainstream social-media spaces like Instagram in July. The Wayfair theory was created by a QAnon influencer, Insider found.
Lifestyle influencers, mommy bloggers, and yogis began to espouse QAnon rhetoric online. This group's QAnon beliefs are more tied to the idea of a secretive, shadowy cabal than to Trump being our savior. It's this version of QAnon that's also spread to other countries, including Germany.
Study reveals substantial evidence of holographic universe
A sketch of the timeline of the holographic Universe. Time runs from left to right. The far left denotes the holographic phase and the image is blurry because space and time are not yet well defined. At the end of this phase (denoted by the black fluctuating ellipse) the Universe enters a geometric phase, which can now be described by Einstein's equations. The cosmic microwave background was emitted about 375,000 years later. Patterns imprinted in it carry information about the very early Universe and seed the development of structures of stars and galaxies in the late time Universe (far right). Credit: Paul McFadden
A UK, Canadian and Italian study has provided what researchers believe is the first observational evidence that our universe could be a vast and complex hologram.
Theoretical physicists and astrophysicists, investigating irregularities in the cosmic microwave background (the 'afterglow' of the Big Bang), have found there is substantial evidence supporting a holographic explanation of the universe—in fact, as much as there is for the traditional explanation of these irregularities using the theory of cosmic inflation.
The researchers, from the University of Southampton (UK), University of Waterloo (Canada), Perimeter Institute (Canada), INFN, Lecce (Italy) and the University of Salento (Italy), have published findings in the journal Physical Review Letters.
A holographic universe, an idea first suggested in the 1990s, is one where all the information that makes up our 3-D 'reality' (plus time) is contained in a 2-D surface on its boundaries.
Professor Kostas Skenderis of Mathematical Sciences at the University of Southampton explains: "Imagine that everything you see, feel and hear in three dimensions (and your perception of time) in fact emanates from a flat two-dimensional field. The idea is similar to that of ordinary holograms where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card. However, this time, the entire universe is encoded."
Although not an example with holographic properties, it could be thought of as rather like watching a 3-D film in a cinema. We see the pictures as having height, width and crucially, depth—when in fact it all originates from a flat 2-D screen. The difference, in our 3-D universe, is that we can touch objects and the 'projection' is 'real' from our perspective.
In recent decades, advances in telescopes and sensing equipment have allowed scientists to detect a vast amount of data hidden in the 'white noise' or microwaves (partly responsible for the random black and white dots you see on an un-tuned TV) left over from the moment the universe was created. Using this information, the team were able to make complex comparisons between networks of features in the data and quantum field theory. They found that some of the simplest quantum field theories could explain nearly all cosmological observations of the early universe.
Professor Skenderis comments: "Holography is a huge leap forward in the way we think about the structure and creation of the universe. Einstein's theory of general relativity explains almost everything large scale in the universe very well, but starts to unravel when examining its origins and mechanisms at quantum level. Scientists have been working for decades to combine Einstein's theory of gravity and quantum theory. Some believe the concept of a holographic universe has the potential to reconcile the two. I hope our research takes us another step towards this."
The scientists now hope their study will open the door to further our understanding of the early universe and explain how space and time emerged.