volume 40 number 04 - department of physics and...
TRANSCRIPT
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COMING EVENTS Public Observing
Prairie Park Nature Center Sunday, April 27
9:00 PM
Monthly Meetings FRIDAY, April 25
7:30 PM 1001 Malott
THE BICEP REVOLUTION
President Rick Heschmeyer
Webmaster Howard Edin
Observing Clubs Doug Fay
[email protected] ALCOR
William Winkler [email protected]
University Advisor Dr. Bruce Twarog [email protected]
Report from the Officers With Spring Break, and the early exit of KU from the NCAA tourna-ment behind us, we return to something resembling a regular meeting schedule. I say resem-bling because the original plan was to have our next meeting the 2nd Friday in April, but events intervened to change that date. The event I’m referring to is the announcement of the BICEP
results, an astronomical observation program in Antarctica which is being touted as a revolutionary experiment in the history of cosmology and, especially, gravitational physics. There is a summary from Dennis Overbye below. To help people understand
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Volume 40 Number 04 April 2014
INSIDE THIS ISSUE
BICEP Ripples (continued) 2
Zoomable Spitzer 3
NASA Space Place 4
APRIL MEETING POSTER 5
Black Hole Seeds 6
Too Fast, Too Furious 7
Asteroid (continued) 7
Asteroid Disintegration 8
Comet Jets 9
BICEP (continued) 9
BICEP (continued) 10
Spitzer (continued) 10
Of Local Interest Space Ripples Reveal Big Bang’s Smoking Gun Dennis Overbye, NY Times One night late in 1979, an itinerant young physicist named Alan Guth, with a new son and a year’s appointment at Stanford, stayed up late with his notebook and equa-tions, venturing far beyond the world of known physics. He was trying to understand why there was no trace of some exotic particles that should have been created in the Big Bang. Instead he discovered what might have made the universe bang to begin with. A potential hitch in the presumed course of cosmic evolution could have infused space itself with a special energy that exerted a repulsive force, causing the universe to swell faster than the speed of light for a prodigiously violent instant. If true, the rapid engorgement would solve paradoxes like why the heavens look uni-form from pole to pole and not like a jagged, warped mess. The enormous ballooning would iron out all the wrinkles and irregularities. Those particles were not missing, but would be diluted beyond detection, like spit in the ocean. “SPECTACULAR REALIZATION,” Dr. Guth wrote across the top of the page and drew a double box around it. On Monday, Dr. Guth’s starship came in. Radio astrono-mers reported that they had seen the beginning of the Big Bang, and that his hypoth-esis, known undramatically as inflation, looked right. Reaching back across 13.8 bil-lion years to the first sliver of cosmic time with telescopes at the South Pole, a team of astronomers led by John M. Kovac of the Harvard-Smithsonian Center for Astro-physics detected ripples in the fabric of space-time — so-called gravitational waves — the signature of a universe being wrenched violently apart when it was roughly a trillionth of a trillionth of a trillionth of a second old. They are the long-sought smoking-gun evidence of inflation, proof, Dr. Kovac and his colleagues say, that Dr. Guth was correct. Inflation has been the workhorse of cosmology for 35 years, though many, including Dr. Guth, wondered whether it could ever be proved. If corroborated, Dr. Kovac’s work will stand as a landmark in science comparable to the recent discovery of dark energy pushing the universe apart, or of the Big Bang itself. It would open vast realms of time and space and energy to science and speculation. Confirming inflation would mean that the universe we see, extending 14 billion light-years in space with its hundreds of billions of galaxies, is only an infinitesimal patch in a larger cosmos
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About the Astronomy Associates of Lawrence
The club is open to all people interested in sharing their love for astronomy. Monthly meetings are typically on the second Friday of each month and often feature guest speakers, presentations by club members, and a chance to exchange amateur astronomy tips. Approximately the last Sunday of each month we have an open house at the Prairie Park Nature Center. Periodic star parties
are scheduled as well. For more information, please contact the club officers: president, Rick Heschmeyer at
[email protected]; webmaster, Howard Edin, at [email protected]; AlCor William Winkler, at
[email protected]; or faculty advisor, Prof. Bruce Twarog at [email protected]. Because of the flexibility of the schedule due to holidays and alternate events, it is always best to check the Web site for the exact Fridays and Sundays when events are
scheduled. The information about AAL can be found at http://groups.ku.edu/~astronomy
Copies of the Celestial Mechanic can also be found on the web at http://groups.ku.edu/~astronomy/celestialmechanic
what makes this result so important, we’ve arranged for a talk at the next meeting by Dr. Hume Feldman, Chair of Physics & Astronomy and an internationally renowned cosmologist. To accommodate his schedule, we have rescheduled the APRIL meeting to Friday April 25. Note also that due to the expected (hopefully)
large crowd, we will hold the meeting and talk in our old stomping grounds, 1001 Malott. So, please attend
and, because this is a very special event, try to bring as many friends and family along to see if we can fill the auditorium. Well, at least it didn’t snow! Our last public observing session on March 30 was cancelled due to cloudy skies and winds gusting to 40 mph. We will try again on Sunday April 27 at 9:00 PM. We are also closing in on the summer break period so we need to begin talking about the downtown observing schedule after the Band concerts starting in late May. ALCON 2014 Website is now "LIVE" The annual Astronomical League Convection this year is in San Antonio, Texas – July 10, 11, & 12, 2014. Log on to the site (http://alcon2014.astroleague.org/) and check the plans and registration in detail. Time to image Mars: Mars opposition is about one week away so its time to get out there and take some images of the red planet! With the latest generation of imaging cameras and software you can get reasonably good images even with only fair-to-poor turbulent conditions. For more insight, go to http://astroleague.org/content/time-image/mars/ Any suggestions for improving the club or the newsletter are always welcome.
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whose extent, architecture and fate are unknowable. Moreover, beyond our own universe there might be an endless number of other universes bubbling into frothy eternity, like a pot of pasta water boiling over. ‘As Big as It Gets’ In our own universe, it would serve as a window into the forces operating at energies forever beyond the reach of particle accel-erators on Earth and yield new insights into gravity itself. Dr. Kovac’s ripples would be the first direct observation of gravitational waves, which, according to Einstein’s theory of general relativity, should ruffle space-time. Marc Kamionkowski of Johns Hop-kins University, an early-universe expert who was not part of the team, said, “This is huge, as big as it gets.” +He continued, “This is a signal from the very earliest universe, sending a telegram encoded in gravitational waves.” The ripples manifested themselves as faint spiral patterns in a bath of microwave radiation that permeates space and preserves a picture of the uni-verse when it was 380,000 years old and as hot as the surface of the sun. Dr. Kovac and his collaborators, working in an experiment known as Bicep, for Background Imaging of Cosmic Extragalactic Polarization, reported their results in a scientific briefing at the Center for Astrophysics here on Monday and in a set of papers submitted to The Astrophysical Journal. Dr. Kovac said the chance that the results were a fluke was only one in 10 million. Dr. Guth, now 67, pronounced himself “bowled over,” saying he had not expected such a definite confirmation in his lifetime. “With nature, you have to be lucky,” he said. “Apparently we have been lucky.” The results are the closely guarded distillation of three years’ worth of observations and analysis. Eschewing email for fear of a leak, Dr. Kovac personally delivered drafts of his work to a select few, meeting with Dr. Guth, who is now a professor at Massa-chusetts Institute of Technology (as is his son, Larry, who was sleeping that night in 1979), in his office last week. “It was a very special moment, and one we took very seriously as scientists,” said Dr. Kovac, who chose his words as carefully as he tended his radio telescopes. Andrei Linde of Stanford, a prolific theorist who first described the most popular variant of inflation, known as chaotic inflation, in 1983, was about to go on vacation in the Caribbean last week when Chao-Lin Kuo, a Stanford colleague and a member of Dr. Kovac’s team, knocked on his door with a bottle of Champagne to tell him the news. Confused, Dr. Linde called out to his wife, asking if she had ordered anything. “And then I told him that in the beginning we thought that this was a delivery but we did not think that we ordered anything, but I simply forgot that actually I did order it, 30
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NASA's Spitzer Telescope Brings 360-Degree View of Galaxy to Our Fingertips Spitzer Press Release
Touring the Milky Way now is as easy as clicking a button with NASA's new zoomable, 360-degree mosaic present-ed at the TEDActive 2014 Conference in Vancouver, Canada. The star-studded panorama of our galaxy is con-structed from more than 2 million infrared snapshots taken over the past 10 years by NASA's Spitzer Space Tele-scope.
"If we actually printed this out, we'd need a billboard as big as the Rose Bowl Stadium to display it," said Robert Hurt, an imaging specialist at NASA's Spitzer Space Science Center in Pasadena, Calif. "Instead we’ve created a digital viewer that anyone, even astronomers, can use."
The 20-gigapixel mosaic uses Microsoft’s WorldWide Telescope visualization platform. It captures about three per-cent of our sky, but because it focuses on a band around Earth where the plane of the Milky Way lies, it shows more than half of all the galaxy's stars. The image, derived primarily from the Galactic Legacy Mid-Plane Survey Extraordinaire project, or GLIMPSE360, is online at:
http://www.spitzer.caltech.edu/glimpse360
Spitzer, launched into space in 2003, has spent more than 10 years studying everything from asteroids in our solar system to the most remote galaxies at the edge of the observable universe. In this time, it has spent a total of 4,142 hours (172 days) taking pictures of the disk, or plane, of our Milky Way galaxy in infrared light. This is the first time those images have been stitched together into a single expansive view.
Our galaxy is a flat spiral disk; our solar system sits in the outer one-third of the Milky Way, in one of its spiral arms. When we look toward the center of our galaxy, we see a crowded, dusty region jam-packed with stars. Visible-light telescopes cannot look as far into this region because the amount of dust increases with distance, blocking visible starlight. Infrared light, however, travels through the dust and allows Spitzer to view past the galaxy's center.
"Spitzer is helping us determine where the edge of the galaxy lies," said Ed Churchwell, co-leader of the GLIMPSE team at the University of Wisconsin-Madison. "We are mapping the placement of the spiral arms and tracing the shape of the galaxy."
Using GLIMPSE data, astronomers have created the most accurate map of the large central bar of stars that marks the center of the galaxy, revealing the bar to be slightly larger than previously thought. GLIMPSE images have also shown a galaxy riddled with bubbles. These bubble structures are cavities around massive stars, which blast wind and radiation into their surroundings. All together, the data allow scientists to build a more global model of stars, and star formation in the galaxy -- what some call the "pulse" of the Milky Way. Spitzer can see faint stars in the
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A new panorama from NASA's Spitzer Space Telescope shows us our galaxy's plane all the way around us in infra-red light.
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Old Tool, New Use: GPS
and the Terrestrial Refer-
ence Frame By Alex H. Kasprak
Flying over 1300 kilometers above Earth, the Jason 2 satellite knows its distance from the ocean down to a matter of centimeters, allowing for the creation of detailed maps of the ocean’s surface. This information is invaluable to oceanographers and climate scientists. By understanding the ocean’s complex topography—its barely perceptible hills and troughs—these scientists can monitor the pace of sea level rise, unravel the intricacies of ocean currents, and project the effects of future climate change. But these measurements would be useless if there were not some frame of reference to put them in context. A ter-restrial reference frame, ratified by an international group of scientists, serves that purpose. “It’s a lot like air,” says JPL scientist Jan Weiss. “It’s all around us and is vitally important, but people don’t really think about it.” Creating such a frame of reference is more of a challenge than you might think, though. No point on the surface of Earth is truly fixed.
To create a terrestrial reference frame, you need to know the distance between as many points as possible. Two methods help achieve that goal. Very-long baseline interferometry uses multiple radio antennas to monitor the sig-nal from something very far away in space, like a quasar. The distance between the antennas can be calculated based on tiny changes in the time it takes the signal to reach them. Satellite laser ranging, the second method, bounces lasers off of satellites and measures the two-way travel time to calculate distance between ground sta-tions.
Weiss and his colleagues would like to add a third method into the mix—GPS. At the moment, GPS measurements are used only to tie together the points created by very long baseline interferometry and satellite laser ranging to-gether, not to directly calculate a terrestrial reference frame.
“There hasn’t been a whole lot of seri-ous effort to include GPS directly,” says Weiss. His goal is to show that GPS can be used to create a terrestrial refer-ence frame on its own. “The thing about GPS that’s different from very-long baseline interferometry and satellite laser ranging is that you don’t need complex and expensive infrastructure and can deploy many stations all around the world.”
Feeding GPS data directly into the cal-culation of a terrestrial reference frame could lead to an even more accurate and cost effective way to reference points geospatially. This could be good news for missions like Jason 2. Slight errors in the terrestrial reference frame can create significant errors where pre-cise measurements are required. GPS stations could prove to be a vital and untapped resource in the quest to cre-ate the most accurate terrestrial refer-ence frame possible. “The thing about GPS,” says Weiss, “is that you are just so data rich when compared to these other techniques.”
You can learn more about NASA’s efforts to create an accurate terrestrial reference frame here: http://space-geodesy.nasa.gov/. Kids can learn all about GPS by visiting http://spaceplace.nasa.gov/gps and watching a fun animation about finding pizza here: http://spaceplace.nasa.gov/gps-pizza.
Artist’s interpretation of the Jason 2 satellite. To do its job properly, satellites
like Jason 2 require as accurate a terrestrial reference frame as possible. Image
courtesy: NASA/JPL-Caltech.
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The artist concept depicts multiple-transiting planet systems, which are stars with more than one planet. The plan-ets eclipse or transit their host star from the vantage point of the observer. This angle is called edge-on.
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The Search for Seeds of Black Holes
How do you grow a supermassive black hole that is a million to a billion times the mass of our sun? Astronomers do not know the answer, but a new study using data from NASA's Wide-field Infrared Survey Explorer, or WISE, has turned up what might be the cosmic seeds from which a black hole will sprout. The results are helping scientists piece together the evolution of supermassive black holes -- powerful objects that dominate the hearts of all galaxies.
Growing a black hole is not as easy as planting a seed in soil and adding water. The massive objects are dense collec-tions of matter that are literally bottomless pits; anything that falls in will never come out. They come in a range of sizes. The smallest, only a few times greater in mass than our sun, form from exploding stars. The biggest of these dark beasts, billions of times the mass of our sun, grow together with their host galaxies over time, deep in the interiors. But how this process works is an ongoing mystery.
Researchers using WISE addressed this question by looking for black holes in smaller, "dwarf" galaxies. These galaxies have not undergone much change, so they are more pristine than their heavier counterparts. In some ways, they resem-ble the types of galaxies that might have existed when the universe was young, and thus they offer a glimpse into the nurseries of supermassive black holes.
In this new study, using data of the entire sky taken by WISE in infrared light, up to hundreds of dwarf galaxies have been discovered in which buried black holes may be lurking. Infrared light, the kind that WISE collects, can see through dust, unlike visible light, so it's better able to find the dusty, hidden black holes. The researchers found that the dwarf galaxies' black holes may be about 1,000 to 10,000 times the mass of our sun -- larger than expected for these small galaxies.
"Our findings suggest the original seeds of supermassive black holes are quite massive themselves," said Shobita Satyapal of George Mason University, Fairfax, Va. Satyapal is lead author of a paper published in the March issue of As-trophysical Journal.
Daniel Stern, an astronomer specializing in black holes at NASA's Jet Propulsion Laboratory, Pasadena, Calif., who was not a part of the new study, says the re-search demonstrates the power of an all-sky survey like WISE to find the rarest black holes. "Though it will take more re-search to confirm whether the dwarf galaxies are indeed dominated by actively feeding black holes, this is exactly what WISE was designed to do: find interesting objects that stand out from the pack."
The new observations argue against one popular theory of black hole growth, which holds that the objects bulk up in
size through galaxy collisions. When our universe was young, galaxies were more likely to crash into others and merge. It is possible the galaxies' black holes merged too, accumulating more mass. In this scenario, supermassive black holes grow in size through a series of galaxy mergers.
The discovery of dwarf galaxy black holes that are bigger than expected suggests that galaxy mergers are not necessary to create big black holes. Dwarf galaxies don't have a history of galactic smash-ups, and yet their black holes are already relatively big.
Instead, supermassive black holes might form very early in the history of the universe. Or, they might grow harmoniously with their host galaxies, feeding off surrounding gas.
"We still don't know how the monstrous black holes that reside in galaxy centers formed," said Satyapal. "But finding big black holes in tiny galaxies shows us that big black holes must somehow have been created in the early universe, before galaxies collided with other galaxies."
The galaxy NGC 4395 is shown here in infrared light, captured by NASA's Spitzer Space Tele-scope. This dwarf galaxy is relatively small in comparison with our Milky Way galaxy, which is nearly 1,000 times more massive.
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Life Is Too Fast, Too Furious for This Runaway Galaxy HST PRESS RELEASE
Our spiral-shaped Milky Way galaxy lives in a comparatively quiet backwater region of the universe. This is not the case for galaxies crammed together inside huge clusters. As they zip around within a cluster, gas can be pulled from their disks due to a process called ram pressure stripping. Galaxy ESO 137-001 is one example. The star-city looks like it is "leaking" as it plunges through the Norma galaxy cluster.
sional shattering of a bigger body some time in the last billion years.
With the previous discovery of an active asteroid spouting six tails (P/2013 P5), astronomers are seeing more cir-cumstantial evidence that the pressure of sunlight may be the primary force that disintegrates small asteroids (less than a mile across) in the solar system.
The asteroid's remnant debris, weighing in at 200,000 tons, will in the future provide a rich source of meteoroids. Most will eventually plunge into the Sun but a small fraction of the debris may one day hit the Earth to blaze across the sky as meteors.
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Hubble Witnesses an Asteroid Mysteriously Disintegrating HST Press Release
NASA's Hubble Space Telescope has photographed the never-before-seen breakup of an asteroid into as many as 10 smaller pieces. Though fragile comet nuclei have been seen falling apart as they near the Sun, nothing like this breakup has ever before been observed in the asteroid belt.
"This is a rock. Seeing it fall apart before our eyes is pretty amazing," said David Jewitt of UCLA, who led the astro-nomical forensics investigation. The crumbling asteroid, designated P/2013 R3, was first noticed as an anomalous, fuzzy-looking object on Sept. 15, 2013, by the Catalina and Pan-STARRS sky surveys. A follow-up observation on October 1 with the W. M. Keck Observatory on the summit of Mauna Kea, Hawaii revealed three co-moving bodies embedded in a dusty envelope that is nearly the diameter of Earth.
"Keck showed us that this thing was worth look-ing at with Hubble," Jewitt said. With its superior resolution, Hubble observations soon showed that there were really 10 embedded objects, each with comet-like dust tails. The four largest rocky fragments are up to 200 yards in radius, about twice the length of a football field.
The Hubble data showed that the fragments are drifting away from each other at a leisurely one mile per hour — slower than the speed of a strolling human. The asteroid began coming apart early last year, but new pieces continue to emerge in the most recent images. This makes it unlikely that the asteroid is disintegrating be-cause of a collision with another asteroid, which would be instantaneous and violent by compari-son to what has been observed. Some of the debris from such a high-velocity smashup would also be expected to travel much faster than ob-served.
Nor is the asteroid coming unglued due to the pressure of interior ices warming and vaporizing. The asteroid is too cold for ices to significantly sublimate, and it has presumably maintained its nearly 300-million-mile distance from the Sun for much of the age of the solar system. This leaves a scenario in which the asteroid is disintegrating due to a subtle effect of sunlight, which causes the rotation rate to slowly increase. Eventually, its component pieces, like grapes on a stem, gently pull apart due to centrifugal force. The possibility of disruption by this so-called YORP torque has been discussed by scientists for several years but, so far, never reliably observed.
For this to happen, P/2013 R3 must have a weak, fractured interior, probably as the result of numer-ous, ancient, non-destructive collisions with other asteroids. Most small asteroids, in fact, are thought to have been severely damaged in this way, giving them a "rubble pile" internal structure. P/2013 R3 itself is probably the product of colli-
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This series of Hubble Space Telescope images reveals the breakup of an asteroid over a period of several months starting in late 2013. The largest fragments are up to 180 meters (200 yards) in radius, each with "tails" caused by dust lifted from their surfaces and pushed back by the pressure of sunlight. The ten pieces of the asteroid drift apart slowly and show a range of breakup times, suggesting that the disintegration can-not be explained by a collision with another asteroid. One idea for the breakup is that the asteroid was accelerated by sunlight to spin at a fast enough rate to fly apart by centrifugal force. The images were taken in visible light with Hubble's Wide Field Camera 3.
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Hubble Sees Mars-Bound Comet Sprout Multiple Jets Comet Siding Spring is plunging toward the Sun along a roughly 1-million-year orbit. The comet, discovered in 2013, was within the radius of Jupiter's orbit when the Hubble Space Telescope photographed it on March 11, 2014. Hubble resolves two jets of dust coming from the solid icy nucleus. These persistent jets were first seen in Hubble pictures taken on Oct. 29, 2013. The feature should allow astronomers to measure the direction of the nucleus's pole, and hence, rotation axis. The comet will make its closest approach to our Sun on Oct. 25, 2014, at a distance of 130 million miles, well outside Earth's orbit. On its inbound leg, Comet Siding Spring will pass within 84,000 miles of Mars on Oct. 19, 2014, which is less than half the Moon's distance from Earth. The comet is not expected to become bright enough to be seen by the naked eye.
years ago,” Dr. Linde wrote in an email. Calling from Bonaire, the Dutch Caribbean island, Dr. Linde said he was still hyperventilating. “Having news like this is the best way of spoiling a vacation,” he said. By last weekend, as social media was buzzing with rumors that inflation had been seen and news spread, astrophysicists responded with a mixture of jubilation and caution. Max Tegmark, a cosmologist at M.I.T., wrote in an email, “I think that if this stays true, it will go down as one of the greatest discoveries in the history of science.” John E. Carlstrom of the University of Chicago, Dr. Kovac’s mentor and head of a competing project called the South Pole Telescope, pronounced himself deeply impressed. “I think the results are beautiful and very convinc-ing,” he said. Paul J. Steinhardt of Princeton, author of a competitor to inflation that posits the clash of a pair of universes as the cause of genesis, said that if true, the Bicep result would eliminate his model, but he expressed reservations about inflation. Lawrence M. Krauss of Arizona State and others also emphasized the need for confirmation, noting that the new results exceeded earlier estimates based on temperature maps of the cosmic background by the European Space Agency’s Planck satellite and other assumptions about the universe. “So we will need to wait and see before we jump up and down,” Dr. Krauss said. Corroboration might not be long in coming. The Planck spacecraft will report its own findings this year. At least a dozen other teams are trying similar measurements from balloons, mountain-tops and space. Gravity waves are the latest and deepest secret yet pried out of the cosmic microwaves, which were discovered accidentally by Arno Penzias and Robert Wilson at Bell Labs 50 years ago. They won the Nobel Prize. Dr. Kovac has spent his career trying to read the secrets of these waves. He is one of four leaders of Bicep, which has operated a series of increasingly sensitive radio telescopes at the South Pole, where the thin, dry air creates ideal observing conditions. The others are Clement Pryke of the University of Minnesota, Jamie Bock of the Cali-
fornia Institute of Technology and Dr. Kuo of Stanford. “The South Pole is the closest you can get to space and
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AAL Astronomy Associates of Lawrence
University of Kansas Malott Hall 1251 Wescoe Hall Dr, Room 1082 Lawrence, KS 66045-7582
Celestial Mechanic April 2014
"backcountry" of our galaxy -- the outer, darker regions that went largely unexplored before.
"There are a whole lot more lower-mass stars seen now with Spitzer on a large scale, allowing for a grand study," said Barbara Whitney of the University of Wisconsin, Madison, co-leader of the GLIMPSE team. "Spitzer is sensitive enough to pick these up and light up the entire 'countryside' with star formation."
The Spitzer team previously released an image compilation showing 130 degrees of our galaxy, focused on its hub. The new 360-degree view will guide NASA's upcoming James Webb Space Telescope to the most interesting sites of star-formation, where it will make even more detailed infrared observations.
Some sections of the GLIMPSE mosaic include longer-wavelength data from NASA's Wide-field Infrared Survey Explorer, or WISE, which scanned the whole sky in infrared light.
The GLIMPSE data are also part of a citizen science project, where users can help catalog bubbles and other ob-jects in our Milky Way galaxy. To participate, visit: http://www.milkywayproject.org
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still be on the ground,” Dr. Kovac said. He has been there 23 times, he said, wintering over in 1994. “I’ve been hooked ever since,” he said. In 2002, he was part of a team that discovered that the micro-wave radiation was polarized, meaning the light waves had a slight preference to vibrate in one direction rather than another.This was a step toward the ultimate goal of detecting the gravitational waves from inflation. Such waves, squeezing space in one direction and stretching it in another as they go by, would twist the direction of polarization of the microwaves, theorists said. As a result, maps of the polarization in the sky should have little arrows going in spirals. Detecting those spirals required measuring infinitesi-mally small differences in the temperature of the microwaves. The group’s telescope, Bicep2, is basical-ly a giant superconducting thermometer. “We had no expectations what we would see,” Dr. Kovac said. The strength of the signal surprised the researchers, and they spent a year burning up time on a Har-vard supercomputer, making sure they had things right and worrying that competitors might beat them to the breakthrough.
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