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COMING EVENTS Observing the Supermoon MONDAY, NOV. 14, 7-8 PM Lawrence Public Library

Parking Lot

AAL Meeting Baker Wetlands

Discovery Center SUNDAY, DEC. 04, 7:00 PM

PUBLIC OBSERVING 8:30 PM

President

Rick Heschmeyer rcjbm@sbcglobal.net

ALCOR

William Winkler billwink10@yahoo.com

Report from the Officers At our October meeting, we had an entertaining talk by Gary Hug, retired machinist and amateur astrono-mer extraordinaire. In addition to helping build and maintain Farpoint Observatory, owned and operated by the NorhtEast Kansas Amateur Astronomy League, west of Auburn, KS, Gary has built his own backyard observatory with a 22-inch reflector. Both telescopes have been heavily used over the last 20 and last three years respectively to search for NE-O’s, Near Earth Objects, that have the potential to do serious damage if they ever cross the path of the Earth. For more on Gary and his private observatory, check out the video at this link. The weather kept the string alive—we are now 0 for 6 in scheduled open houses. Fortunately, Bill Wach-spress was kind enough to open the dome and show the scope and a few bright stars to a visiting

group of students and their parents, who attended the meeting and observing session as part of their class exercise on Space. Our next shot at confounding the weather gods will be on MONDAY NOV. 14, when the club cosponsors the supermoon viewing in downtown Lawrence. Please look over the story below and see if you would be will-ing to lend a hand. Our next meeting will be after Thanksgiving Break, the first weekend in Dec., to be exact. Our speaker will be Dr. Anthony-Twarog of KU with a title/topic yet to be deter-mined. We will pass along the info as soon as it is finalized. Note, however, the Dec.

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Volume 42 Number 11 November 2016

INSIDE THIS ISSUE

Officer’s Report (continued) 2

Supermoon (continued) 2

A Young Globular 3

NASA SPACE PLACE 4

Ghostly Glow 5

Proxima Centauri 6

Proxima (continued) 7

Pumpkin Stars (continued) 7

Galaxies (continued) 7

Pumpkin Stars 8

Galaxies Unlimited 9

Frontier (continued) 10

Cosmic X-Rays (continued) 10

Frontier Fields 11

Cosmic X-Rays 12

SUPERMOON 2016 This year, the full moons of October, November and December all take place when the moon is at its closest point of approach in its orbit around Earth — a so-called supermoon. October's supermoon occurred on Oct. 16. The next supermoon will be November's full Beaver Moon, which is expected to reach the peak of its full phase on the morning of Nov. 14, at 8:52 a.m. EST (1352 GMT). This full moon will be not only the closest and brightest supermoon of 2016 but also the largest since 1948. What's more, the full moon won't come this close to Earth again until Nov. 25, 2034, according to a statement from NASA. As part of the wrap-up to the Lawrence Public Library Course—History of Human Space Flight – the Astronomy Associates of Lawrence will sponsor a

SuperMoon Viewing Party from 7:00—8:00 PM from the top landing of the parking garage south of the Library. Setup for the event will take place between 6 and 7 PM and the roof has to be va-cated by 9 PM. Since the primary function is to focus on the moon, this will not re-quire extensive experience with using a telescope but should provide a great oppor-tunity to interact with the public. If you can help in any way, please contact Rick.

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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

rcjbm@sbcglobal.net; webmaster, Howard Edin, at howard@howardedin.com; AlCor William Winkler, at

billwink10@yahoo.com; or faculty advisor, Prof. Bruce Twarog at btwarog@ku.edu. 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://www.physics.ku.edu/AAL/

Copies of the Celestial Mechanic can also be found on the web at http://www.physics.ku.edu/AAL/newsletter

meeting will be our annual holiday celebration. Keep your fingers crossed for the weather. With any luck, it will be clear but 10o F! The club has been contacted by the Lawrence Parks and Rec Dept. with the request below: We am looking for someone who could teach a stargazing class for Lawrence Parks and Recreation, specifically the Lifelong program for people age 50 and older (but open to all adults). The class would be held in late spring and Roger Boyd is willing to entertain use of the Discovery Center and their observatory. Would this be of interest to a member of the Astronomy Associates of Lawrence? We like the instructor to plan and define content as they are the expert, but as a starting point I envision a look at visual and binocular viewing, some of the mythology and sci-ence and ending with tips for the 2017 solar eclipse which I think will spark interest in the general public. In addition to the Discovery Center, we have access to a bus available that could transport class members to good viewing are-as. Class length of 90-120 minutes has been successful with other topics. If you feel capable of and interested in handling this, please contact Bruce Twarog at btwarog@ku.edu for more info. Any suggestions for improving the club or the newsletter are always welcome.

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October 23, 2014. Image of the Sun showing at least 4 sunspot groups. The notch taken out of the Sun at the right of the image represents a (very) partial solar eclipse seen in Houston on that day. The eclipse was not total anywhere on Earth. The cloudy areas near the top and the bot-tom of the image are, in fact, clouds. Credit: Bill Pellerin

Hubble Admires a Youthful Globular Star Cluster

Globular clusters offer some of the most spectacular sights in the night sky. These ornate spheres contain hun-dreds of thousands of stars, and reside in the outskirts of galaxies. The Milky Way contains over 150 such clusters — and the one shown in this NASA/ESA Hubble Space Telescope image, named NGC 362, is one of the more unusual ones. As stars make their way through life they fuse elements together in their cores, creating heavier and heavier elements — known in astronomy as metals — in the process. When these stars die, they flood their sur-roundings with the material they have formed during their lifetimes, enriching the interstellar medium with metals. Stars that form later therefore contain higher proportions of metals than their older relatives. By studying the differ-ent elements present within individual stars in NGC 362, astronomers discovered that the cluster boasts a surpris-ingly high metal content, indicating that it is younger than expected. Although most globular clusters are much old-er than the majority of stars in their host galaxy, NGC 362 bucks the trend, with an age lying between 10 and 11 billion years old. For reference, the age of the Milky Way is estimated to be above 13 billion years. This image, in which you can view NGC 362’s individual stars, was taken by Hubble’s Advanced Camera for Sur-veys (ACS).

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Images credit: an artist's concept of the JPSS-2 Satellite for NOAA and NASA by Orbital ATK (top); complete temperature map of the world from NOAA's National Weather Service (bottom).

Is Proxima Centauri's 'Earth-like' planet actually like Earth at all?

By Ethan Siegel

Just 25 years ago, scientists didn’t know if any stars—other than our own sun, of course—had planets orbiting around them. Yet they knew with certainty that gravity from massive planets caused the sun to move around our solar sys-tem’s center of mass. Therefore, they reasoned that other stars would have periodic changes to their motions if they, too, had planets.

This change in motion first led to the detection of planets around pulsars in 1991, thanks to the change in pulsar timing it caused. Then, finally, in 1995 the first exoplanet around a normal star, 51 Pegasi b, was discovered via the “stellar wobble” of its parent star. Since that time, over 3000 exoplanets have

been confirmed, most of which were first discovered by NASA's Kepler mission using the transit method. These transits only work if a solar system is fortuitously aligned to our perspective; nevertheless, we now know that plan-ets—even rocky planets at the right distance for liquid water on their surface—are quite common in the Milky Way.

On August 24, 2016, scientists announced that the stellar wobble of Proxima Centauri, the closest star to our sun, indicated the existence of an exoplanet. At just 4.24 light years away, this planet orbits its red dwarf star in just 11 days, with a lower limit to its mass of just 1.3 Earths. If verified, this would bring the number of Earth-like planets found in their star's habitable zones up to 22, with 'Proxima b' being the closest one. Just based on what we've seen so far, if this planet is real and has 130 percent the mass of Earth, we can already infer the following: It receives 70 percent of the sunlight incident on Earth, giving it the right temperature for liquid water on its surface, assuming an Earth-like atmosphere. It should have a radius approximately 10 percent larger than our own planet's, assuming it is made of similar elements. It is plausible that the planet would be tidally locked to its star, implying a permanent 'light side' and a permanent 'dark side'.

And if so, then seasons on this world are deter-mined by the orbit's ellipticity, not by axial tilt.

Yet the unknowns are tremendous. Proxima Centauri emits consid-erably less ultraviolet light than a star like the sun; can life begin with-out that? Solar flares and winds are much greater around this world; have they stripped away the at-mosphere entirely? Is the far side permanently frozen, or do winds al-low possible life there? Is the near side baked and barren, leaving only the 'ring' at the edge potentially habitable?

Proxima b is a vastly different world from Earth, and could range anywhere from actually inhabited to completely unsuitable for any form of life. As 30m-class telescopes and the next generation of space observatories come online, we just may find out!

Looking to teach kids about exoplanet discovery? NASA Space Place explains stellar wobble and how this phe-nomenon can help scientists find exoplanets: http://spaceplace.nasa.gov/barycenter/en/

An artist’s conception of the exoplanet Kepler-452b (R), a possible candidate for Earth 2.0, as

compared with Earth (L). Image credit: NASA/Ames/JPL-Caltech/T. Pyle.

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A Death Star's Ghostly Glow In writer Edgar Allan Poe's short story "The Tell-Tale Heart," a killer confesses his crime after he thinks he hears the beating of his victim's heart. The heartbeat turns out to be an illusion. Astronomers, however, discovered a real "tell-tale heart" in space, 6,500 light-years from Earth. The "heart" is the crushed core of a long-dead star, called a neutron star, which exploded as a supernova and is now still beating with rhythmic precision. Evidence of its heart-beat are rapid-fire, lighthouse-like pulses of energy from the fast-spinning neutron star. The stellar relic is embed-ded in the center of the Crab Nebula, the expanding, tattered remains of the doomed star.

The nebula was first identified in 1731 and named in 1844. In 1928, Edwin Hubble linked the nebula to a superno-va first witnessed in the spring of 1054 A.D. Now, the eerie glow of the burned-out star reveals itself in this new Hubble Space Telescope snapshot of the heart of the Crab Nebula. The green hue, representative of the broad color range of the camera filter used, gives the nebula a Halloween theme.

The eerie glow of a dead star, which exploded long ago as a supernova, reveals itself in this NASA Hubble Space Telescope image of the Crab Nebula. But don't be fooled. The ghoulish-looking object still has a pulse. Buried at its center is the star's tell-tale heart, which beats with rhythmic precision.The "heart" is the crushed core of the exploded star. Called a neutron star, it has about the same mass as the sun but is squeezed into an ultra-dense sphere that is only a few miles across and 100 billion times stronger than steel. The tiny powerhouse is the bright star-like object near the center of the image. This surviving remnant is a tremendous dynamo, spinning 30 times a second. The wildly whirling object produces a deadly magnetic field that generates an electrifying 1 trillion volts. This energetic activity unleashes wisp-like waves that form an expanding ring, most easily seen to the upper right of the pulsar. The nebula's hot gas glows in radiation across the electromagnetic spectrum, from radio to X-rays. The Hubble exposures were taken in visible light as black-and-white exposures. The Advanced Camera for Sur-veys made the observations between January and September 2012. The green hue, representative of the broad color range of the camera filter used, gives the nebula a Halloween theme. The Crab Nebula is one of the most historic and intensively studied supernova remnants. Observations of the nebula date back to 1054 A.D., when Chinese astronomers first recorded seeing a "guest star" during the daytime for 23 days. The star appeared six times brighter than Venus. Japanese, Arabic, and Native American stargazers also recorded seeing the mystery star. In 1758, while searching for a comet, French astronomer Charles Messier discovered a hazy nebula near the location of the long-vanished supernova. He later added the nebula to his celestial catalog as "Messier 1," marking it as a "fake comet." Nearly a century later British astronomer William Parsons sketched the nebula. Its resem-blance to a crustacean led to M1's other name, the Crab Nebula. In 1928 astronomer Edwin Hubble first proposed associating the Crab Nebula to the Chinese "guest star" of 1054. The nebula, bright enough to be visible in ama-teur telescopes, is located 6,500 light-years away in the constellation Taurus.

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Proxima Centauri Might Be More Sunlike Than We Thought

In August astronomers announced that the nearby star Proxima Centauri hosts an Earth-sized planet (called Proxi-ma b) in its habitable zone. At first glance, Proxima Centauri seems nothing like our Sun. It’s a small, cool, red dwarf star only one-tenth as massive and one-thousandth as luminous as the Sun. However, new research shows that it is sunlike in one surprising way: it has a regular cycle of starspots.

Starspots (like sunspots) are dark blotches on a star’s surface where the temperature is a little cooler than the sur-rounding area. They are driven by magnetic fields. A star is made of ionized gases called plasma. Magnetic fields can restrict the plasma’s flow and create spots. Changes to a star’s magnetic field can affect the number and distri-bution of starspots.

Our Sun experiences an 11-year activity cycle. At the solar minimum, the Sun is nearly spot-free. At solar maxi-mum, typically more than 100 sunspots cover less than one percent of the Sun’s surface on average.

The new study finds that Proxima Centauri under-goes a similar cycle lasting seven years from peak to peak. However, its cycle is much more dramatic. At least a full one-fifth of the star’s surface is covered in spots at once. Also, some of those spots are much bigger relative to the star’s size than the spots on our Sun.

“If intelligent aliens were living on Proxima b, they would have a very dra-matic view,” says lead author Brad Wargelin of the Harvard-Smithsonian Center for Astrophysics (CfA).

Astronomers were sur-prised to detect a stellar activity cycle in Proxima Centauri because its interior is expected to be very different from the Sun’s. The outer third of the Sun experiences a roiling motion called

convection, similar to water boiling in a pot, while the Sun’s interior remains relatively still. There is a difference in the speed of rotation between these two regions. Many astronomers think the shear arising from this difference is responsible for generating the Sun’s magnetic activity cycle.

In contrast, the interior of a small red dwarf like Proxima Centauri should be convective all the way into the star’s core. As a result, it shouldn’t experience a regular cycle of activity.

“The existence of a cycle in Proxima Centauri shows that we don’t understand how stars’ magnetic fields are gen-erated as well as we thought we did,” says Smithsonian co-author Jeremy Drake.

The study does not address whether Proxima Centauri’s activity cycle would affect the potential habitability of the planet Proxima b. Theory suggests that flares or a stellar wind, both of which are driven by magnetic fields, could

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red Survey Explorer, and NASA's Galaxy Evolution Explorer observed many parts of it in the ultraviolet. "Our group was looking for variable X-ray sources with optical counterparts seen by Kepler, especially active galaxies, where a central black hole drives the emissions," she explained. Using the X-ray and ultraviolet/optical telescopes aboard Swift, the researchers conducted the Kepler–Swift Active Galaxies and Stars Survey (KSwAGS), imaging about six square degrees, or 12 times the apparent size of a full moon, in the Kepler field.

"With KSwAGS we found 93 new X-ray sources, about evenly split between active galaxies and various types of X-ray stars," said team member Krista Lynne Smith, a graduate student at the University of Maryland, College Park who led the analysis of Swift data. "Many of these sources have never been observed before in X-rays or ultravio-let light."

For the brightest sources, the team obtained spectra using the 200-inch telescope at Palomar Observatory in Cali-fornia. These spectra provide detailed chemical portraits of the stars and show clear evidence of enhanced stellar activity, particularly strong diagnostic lines of calcium and hydrogen.

The researchers used Kepler measurements to determine the rotation periods and sizes for 10 of the stars, which range from 2.9 to 10.5 times larger than the sun. Their surface temperatures range from somewhat hotter to slight-ly cooler than the sun, mostly spanning spectral types F through K. Astronomers classify the stars as subgiants and giants, which are more advanced evolutionary phases than the sun's caused by greater depletion of their pri-mary fuel source, hydrogen. All of them eventually will become much larger red giant stars.

Forty years ago, Ronald Webbink at the University of Illinois, Urbana-Champaign noted that close binary systems cannot survive once the fuel supply of one star dwindles and it starts to enlarge. The stars coalesce to form a sin-gle rapidly spinning star initially residing in a so-called "excretion" disk formed by gas thrown out during the mer-ger. The disk dissipates over the next 100 million years, leaving behind a very active, rapidly spinning star. Howell and his colleagues suggest that their 18 KSwAGS stars formed by this scenario and have only recently dissipated their disks. To identify so many stars passing through such a cosmically brief phase of development is a real boon to stellar astronomers.

"Webbink's model suggests we should find about 160 of these stars in the entire Kepler field," said co-author Elena Mason, a researcher at the Italian National Institute for Astrophysics Astronomical Observatory of Trieste. "What we have found is in line with theoretical expectations when we account for the small portion of the field we observed with Swift." The team has already extended their Swift observations to additional fields mapped by the K2 mission.

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Conselice and his team reached this conclusion using deep-space images from Hubble and the already published data from other teams. They painstakingly converted the images into 3-D, in order to make accurate measure-ments of the number of galaxies at different epochs in the universe's history. In addition, they used new mathemat-ical models, which allowed them to infer the existence of galaxies that the current generation of telescopes cannot observe. This led to the surprising conclusion that in order for the numbers of galaxies we now see and their mass-es to add up, there must be a further 90 percent of galaxies in the observable universe that are too faint and too far away to be seen with present-day telescopes. These myriad small faint galaxies from the early universe merged over time into the larger galaxies we can now observe.

"It boggles the mind that over 90 percent of the galaxies in the universe have yet to be studied. Who knows what interesting properties we will find when we discover these galaxies with future generations of telescopes? In the near future, the James Webb Space Telescope will be able to study these ultra-faint galaxies," said Conselice.

The decreasing number of galaxies as time progresses also contributes to the solution for Olbers' paradox (first formulated in the early 1800s by German astronomer Heinrich Wilhelm Olbers): Why is the sky dark at night if the universe contains an infinity of stars? The team came to the conclusion that indeed there actually is such an abun-dance of galaxies that, in principle, every patch in the sky contains part of a galaxy. However, starlight from the galaxies is invisible to the human eye and most modern telescopes due to the other known factors that reduce visible and ultraviolet light in the universe. Those factors are the reddening of light due to the expansion of space, the universe's dynamic nature, and the absorption of light by intergalactic dust and gas. All combined, this keeps the night sky dark to our vision.

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scour the planet and strip away any atmosphere. In that case, Proxima b might be like Earth’s Moon – located in the habitable zone, but not at all friendly to life.

“Direct observations of Proxima b won’t happen for a long time. Until then, our best bet is to study the star and then plug that information into theories about star-planet interactions,” says co-author Steve Saar.

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NASA Missions Harvest a Passel of ‘Pumpkin’ Stars

Astronomers using observations from NASA's Kepler and Swift missions have discovered a batch of rapidly spin-ning stars that produce X-rays at more than 100 times the peak levels ever seen from the sun. The stars, which spin so fast they've been squashed into pumpkin-like shapes, are thought to be the result of close binary systems where two sun-like stars merge.

"These 18 stars rotate in just a few days on average, while the sun takes nearly a month," said Steve Howell, a senior research scientist at NASA's Ames Research Center in Moffett Field, California, and leader of the team. "The rapid rotation amplifies the same kind of activity we see on the sun, such as sunspots and solar flares, and essentially sends it into overdrive."

The most extreme member of the group, a K-type orange giant dubbed KSw 71, is more than 10 times larger than the sun, rotates in just 5.5 days, and produces X-ray emission 4,000 times greater than the sun does at solar maxi-mum.

These rare stars were found as part of an X-ray survey of the original Kepler field of view, a patch of the sky com-prising parts of the constellations Cygnus and Lyra. From May 2009 to May 2013, Kepler measured the brightness of more than 150,000 stars in this region to detect the regular dimming from planets passing in front of their host stars. The mission was immensely successful, netting more than 2,300 confirmed exoplanets and nearly 5,000

candidates to date. An ongoing extended mission, called K2, continues this work in areas of the sky located along the ecliptic, the plane of Earth's orbit around the sun.

"A side benefit of the Kepler mission is that its initial field of view is now one of the best-studied parts of the sky," said team member Padi Boyd, a researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland, who designed the Swift survey. For example, the entire area was observed in infrared light by NASA's Wide-field Infra-

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This artist's concept illustrates how the most extreme "pumpkin star" found by Kepler and Swift compares with the sun. Both stars are shown to scale. KSw 71 is larger, cooler and redder than the sun and rotates four times faster. Rapid spin causes the star to flatten into a pumpkin shape, which results in brighter poles and a darker equator. Rapid rotation also drives increased levels of stellar activity such as starspots, flares and prominences, producing X-ray emission over 4,000 times more intense than the peak emission from the sun. KSw 71 is thought to have recently formed following the merger of two sun-like stars in a close binary system. Credits: NASA's Goddard Space Flight Center/Francis Reddy.

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Hubble Reveals Observable Universe Contains 10 Times More Galaxies Than Previously Thought

The universe suddenly looks a lot more crowded, thanks to a deep-sky census assembled from surveys taken by NASA's Hubble Space Telescope and other observatories. Astronomers came to the surprising conclusion that there are at least 10 times more galaxies in the observable universe than previously thought. The results have clear implications for galaxy formation, and also helps shed light on an ancient astronomical paradox — why is the sky dark at night?

In analyzing the data, a team led by Christopher Conselice of the University of Nottingham, U.K., found that 10 times as many galaxies were packed into a given volume of space in the early universe than found today. Most of these galaxies were relatively small and faint, with masses similar to those of the satellite galaxies surrounding the Milky Way. As they merged to form larger galaxies the population density of galaxies in space dwindled. This means that galaxies are not evenly distributed throughout the universe's history, the research team reports in a paper to be published in The Astrophysical Journal.

"These results are powerful evidence that a significant galaxy evolution has taken place throughout the universe's history, which dramatically reduced the number of galaxies through mergers between them — thus reducing their total number. This gives us a verification of the so-called top-down formation of structure in the universe," ex-plained Conselice.

One of the most fundamental questions in astronomy is that of just how many galaxies the universe contains. The landmark Hubble Deep Field, taken in the mid-1990s, gave the first real insight into the universe's galaxy popula-tion. Subsequent sensitive observations such as Hubble's Ultra Deep Field revealed a myriad of faint galaxies. This led to an estimate that the observable universe contained about 200 billion galaxies. The new research shows that this estimate is at least 10 times too low.

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This Hubble Space Telescope view reveals thousands of galaxies stretching back into time across billions of light-years of space. The image covers a portion of a large galaxy census called the Great Observatories Origins Deep Survey (GOODS). Besides the myriad of galaxies visible in this image, only 10 percent of the total number of gal-axies in the universe are observable for the current generation of telescopes, according to a new analysis of the GOODS and other Hubble deep-field surveys. The study's researchers concluded that at least 10 times more gal-axies exist in the observable universe than previously thought. According to the research, about 90 percent of galaxies in the observable universe are too faint and too far away to be seen with present-day telescopes.

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should prove to be the most distant galaxies ever glimpsed. The current record-holder, a galaxy called GN-z11, was reported in March by Hubble researchers at the astonishing distance of 13.4 billion light-years, only a few hun-dred million years after the big bang. The discovery of this galaxy did not require gravitational lenses because it is an outlying, extremely bright object for its epoch. With the magnification boost provided by gravitational lenses, the Frontier Fields project will allow researchers to study typical objects at such incredible distances, painting a more accurate and complete picture of the universe’s earliest galaxies.

Astronomers want to understand how these primeval galaxies arose, how their constituent mass developed into stars, and how these stars have enriched the galaxies with chemical elements fused in their thermonuclear furnac-es. To learn about the origin and evolution of the earliest galaxies, which are quite faint, astronomers need to col-lect as much light as possible across a range of frequencies. With sufficient light from these galaxies, astronomers can perform spectroscopy, pulling out details about stars' compositions, temperatures and their environments by examining the signatures of chemical elements imprinted in the light.

"With the Frontier Fields approach," said Capak, "the most remote and faintest galaxies are made bright enough for us to start to say some definite things about them, such as their star formation histories."

Because the universe has expanded over its 13.8-billion-year history, light from extremely distant objects has been stretched out, or redshifted, on its long journey to Earth. Optical light emitted by stars in the gravitational-lensed, background galaxies viewed in the Frontier Fields has therefore redshifted into infrared. Spitzer can use this infra-red light to gauge the population sizes of stars in a galaxy, which in turn gives clues to the galaxy's mass. Combin-ing the light seen by Spitzer and Hubble allows astronomers to identify galaxies at the edge of the observable uni-verse.

Hubble, meanwhile, scans the Frontier Fields galaxy clusters in optical and near-infrared light, which has redshift-ed from ultraviolet light on its journey to Earth. Chandra, for its part, observes the foreground galaxy clusters in high-energy X-rays emitted by black holes and ambient hot gas. Along with Spitzer, the space telescopes size up the masses of the galaxy clusters, including their unseen but substantial dark matter content. Nailing down the clusters' total mass is a critical step in quantifying the magnification and distortion they produce on background galaxies of interest. Recent multi-wavelength results in this vein from the Frontier Fields project regarding the MACS J0416 and MACS J0717 clusters were published in October 2015 and February 2016. These results also brought in radio wave observations from the Karl G. Jansky Very Large Array to see star-forming regions otherwise hidden by gas and dust.

The Frontier Fields collaboration has inspired scientists involved in the effort as they look ahead to delving even deeper into the universe with the James Webb Space Telescope, which is planned for launch in 2018.

"The Frontier Fields has been an entirely community-led project, which is different from the way many projects of this magnitude are typically pursued," said Lisa Storrie-Lombardi of the Spitzer Science Center, also with the Fron-tier Fields project. "People have gotten together and really embraced Frontier Fields." In addition to the six Frontier Fields galaxy clusters, Spitzer has done follow-up observations on other, slightly shal-lower fields Hubble has gazed into, expanding the overall number of cosmic regions where fairly deep observa-tions have been taken. These additional fields will further serve as rich areas of investigation for Webb and future instruments.

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the binary system.

While the nature of these flares is unknown, the team has begun to search for answers. One idea is that the flares represent episodes when matter being pulled away from a companion star falls rapidly onto a black hole or neutron star. This could happen when the companion makes its closest approach to the compact object in an eccentric orbit. Another explanation could involve matter falling onto an intermediate-mass black hole, with a mass of about 800 times that of the Sun for one source and 80 times that of the Sun for the other.

"Now that we've discovered these flaring objects, observational astronomers and theorists alike are going to be working hard to figure out what's happening," said co-author Gregory Sivakoff of the University of Alberta.

One of the sources, located near and presumably associated with the galaxy NGC 4636 at a distance of 47 million light years, was observed with Chandra to flare once. Five flares were detected from the other source, which is located near the galaxy NGC 5128 at a distance of 12 million light years. Four of these flares were seen with Chan-dra and one with XMM-Newton.

The team looked at the X-ray variation of several thousand X-ray sources in Chandra observations of 70 nearby galaxies. Although several examples of flaring X-ray sources were found, none exhibited the behavior of the giant rapid flares reported here.

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The Frontier Fields: Where Primordial Galaxies Lurk In the ongoing hunt for the universe's earliest galaxies, NASA's Spitzer Space Telescope has wrapped up its obser-vations for the Frontier Fields project. This ambitious project has combined the power of all three of NASA's Great Observatories -- Spitzer, the Hubble Space Telescope and the Chandra X-ray Observatory -- to delve as far back in time and space as current technology can allow.

Even with today's best telescopes, it is difficult to gather enough light from the very first galaxies, located more than 13 billion light years away, to learn much about them beyond their approximate distance. But scientists have a tool of cosmic proportions to help in their studies. The gravity exerted by massive, foreground clusters of galaxies bends and magnifies the light of faraway, background objects, in effect creating cosmic zoom lenses. This phenom-enon is called gravitational lensing.

The Frontier Fields observations have peered through the strongest zoom lenses available by targeting six of the most massive galaxy clusters known. These lenses can magnify tiny background galaxies by as much as a factor of one hundred. With Spitzer's new Frontier Fields data, along with data from Chandra and Hubble, astronomers

will learn unprecedented details about the earliest galaxies.

"Spitzer has finished its Frontier Fields observations and we are very excited to get all of this data out to the astro-nomical community," said Peter Capak, a research scientist with the NASA/JPL Spitzer Science Center at Caltech in Pasadena, California, and the Spitzer lead for the Frontier Fields project.

A recent paper presented the full catalog data for two of the six galaxy clusters studied by the Frontier Fields: Abell 2744 -- nicknamed Pandora's Cluster -- and MACS J0416, both located about four billion light years away. The other galaxy clusters selected for Frontier Fields are RXC J2248, MACS J1149, MACS J0717 and Abell 370.

Eager astronomers will comb the Frontier Fields catalogs for the tiniest, dimmest-lensed objects, many of which

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This image of galaxy cluster Abell 2744, also called Pandora's Cluster, was taken by the Spitzer Space Telescope. The gravity of this galaxy cluster is strong enough that it acts as a lens to magnify images of more distant back-ground galaxies. This technique is called gravitational lensing. The fuzzy blobs in this Spitzer image are the mas-sive galaxies at the core of this cluster, but astronomers will be poring over the images in search of the faint streaks of light created where the cluster magnifies a distant background galaxy. The cluster is also being studied by NASA's Hubble Space Telescope and Chandra X-Ray Observatory in a collaboration called the Frontier Fields project. In this image, light from Spitzer's infrared channels is colored blue at 3.6 microns and green at 4.5 microns.

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Mysterious Cosmic Objects Erupting in X-rays Discovered

Astronomers have found a pair of ex-traordinary cosmic objects that dramati-cally burst in X-rays. This discovery, ob-tained with NASA's Chandra X-ray Ob-servatory and ESA's XMM-Newton obser-vatory, may represent a new class of explo-sive events found in space.

The mysterious X-ray sources flare up and become about a hun-dred times brighter in less than a minute, before returning to original X-ray levels after about an hour. At their peak, these objects qualify as ultraluminous X-ray sources (ULXs) that give off hundreds to thousands of times more X-rays than typical binary sys-tems where a star is orbiting a black hole or neutron star.

"We've never seen anything like this," said Jimmy Irwin of the University of Ala-bama, who led the study that appears in the latest issue of the journal Nature. "Astronomers have seen many different

objects that flare up, but these may be examples of an entirely new phenomenon."

While magnetars - young neutron stars with powerful magnetic fields - have been known to produce bright and rapid flares in X-rays, these newly discovered objects are different in key ways. First, magnetars only take a few seconds to tens of seconds to decline in X-rays after a flare. Secondly, these new flaring objects are found in popu-lations of old stars in elliptical galaxies, which are spherical or egg-shaped galaxies that are composed mostly of older stars. This makes it unlikely that these new flaring objects are young, astronomically speaking, like magne-tars are thought to be. Also, these objects are brighter in X-rays during their "calm" periods.

"These flares are extraordinary," said Peter Maksym, a co-author from the Harvard-Smithsonian Center for Astro-physics. "For a brief period, one of the sources became one of the brightest ULX to ever be seen in an elliptical galaxy."

When they are not flaring, these sources appear to be normal binary systems where a black hole or neutron star is pulling material from a companion star similar to the Sun. This indicates that the flares do not significantly disrupt

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