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  • Far out in space, in the center of a seething cosmic maelstrom.

  • Extreme heat. High velocities.

  • Atoms tear, and space literally buckles.

  • Photons fly out across the universe, energized to the limits found in nature.

  • Billions of years later, they enter the detectors of spacecraft stationed above our atmosphere.

  • Our ability to record them is part of a new age of high-energy astronomy, and a new age

  • of insights into nature at its most extreme.

  • What can we learn by witnessing the violent birth of a black hole?

  • There have been times when our understanding of the universe has reached a standstill,

  • when our grasp of the workings of time and space, the nature of matter and energy, do

  • not fully square with what we observe.

  • In those times, opposing world views cannot be resolved.

  • So it was in the spring of 1920, when astronomers debated the scale of the universe.

  • The scene was the National Academy of Sciences in Washington, DC.

  • On one side was the astronomer Harlow Shapley, known for his groundbreaking work on the size

  • of our galaxy and the position of the sun within it.

  • Shapley described the galaxy as an island universe. As large as his measurements suggested

  • it was, it might indeed be all there is.

  • That included mysterious fuzzy shapes known as spiral nebulae. He argued they were merely

  • gas clouds.

  • On the opposing side, Heber Curtis argued that some nebulae were also island universes.

  • That idea was not new.

  • 165 years earlier, the German philosopher Emmanuel Kant described the nebulae as galaxies

  • unto themselves.

  • It is noted only in the Milky Way,” he said,” that whitish clouds are seen; several

  • patches of similar aspect shine with faint light here and there throughout the aether,

  • and if the telescope is turned upon any of these it confronts us with a tight mass of

  • stars.”

  • It took a new generation of powerful telescopes for astronomers to finally measure the distance

  • to those mysterious objects.

  • Within a few years after the Great Debate, Edwin Hubble reported data showing the spiral

  • nebulae lay far beyond the Milky Way. That led to our current understanding of a universe

  • billions of light years across, filled with galaxies, and expanding rapidly.

  • In the years since, essential details about this dynamic universe have stubbornly resisted

  • our inquiries. The deeper we dug into the nature of matter and energy, the more obscure

  • they seemed to become.

  • One of the deepest mysteries of all emerged in the 1960s.

  • That was a time when nations were rapidly expanding and testing their nuclear arsenals.

  • In 1963, the United States, Soviet Union, and the United Kingdom signed the Limited

  • Test Ban Treaty, which prohibited above-ground nuclear testing.

  • To verify compliance, the United States launched six pairs of satellites known as Vela, from

  • the Spanish verb to watch over or keep vigil. They were designed to record a distinctive

  • signal of nuclear explosions, called gamma rays.

  • Gamma rays are an ultra high-energy form of electromagnetic radiation, a term used to

  • describe particles called photons that travel out from an energy source.

  • The lowest-energy form, radio, has a wavelength of up to 300 meters. Though we can’t see

  • them, they are produced naturally, for example, in flashes of lightning.

  • Our eyes are tuned to capture much smaller visible wavelengths down to 400 nanometers,

  • or 400 billionths of a meter.

  • Carrying even more energy, ultraviolet light has a wavelength as short as 10 nanometers.

  • X-Rays, which penetrate soft tissue in our bodies, can be as short as one hundredth of

  • a nanometer.

  • Gamma rays carry so much energy that their wavelength can be less than 10 picometers.

  • That’s below the diameter of an atom.

  • They are known asionizing radiation,” which means heavy exposure can strip electrons

  • from atoms in your body and kill you. Fortunately, gamma rays from space do not penetrate our

  • atmosphere.

  • Still, one theory says that a nearby gamma ray burst might have been responsible for

  • a mass extinction 440 million years ago, by destroying Earth’s ozone layer and allowing

  • in a flood of deadly ultraviolet radiation.

  • Unlike lower-energy forms of electromagnetic radiation, gamma rays are produced by the

  • often violent decay of atomic nuclei in nuclear reactions.

  • On the hunt for clandestine nuclear tests, on July 2, 1967, the Vela 3 and Vela 4 satellites

  • detected a flash of gamma radiation that was unlike a nuclear weapon.

  • As additional Vela satellites were launched, a team at Los Alamos National Lab continued

  • to find these mysterious bursts in their data. They were able to narrow the sky positions

  • of sixteen, and to rule out a terrestrial or solar origin.

  • It would take at least 30 years to figure out what they were.

  • A year after the launch of the Hubble Space Telescope in 1990, the 17-ton Compton Gamma

  • Ray Observatory was sent up, in part, to produce a comprehensive map of gamma ray bursts.

  • Over a thousand detections showed the bursts were randomly spread across the sky. That

  • led to another great debate, held in 1995, to stimulate fresh thinking on this long running

  • mystery.

  • Donald Lamb of the University of Chicago argued that they came from a recently discovered

  • crop of neutron stars that had escaped into the halo of our galaxy.

  • Bohdan Paczynski of Princeton University argued that their locations followed the general

  • layout of galaxies and quasars.

  • But at those distances, he conceded, the bursts would have to be the most luminous objects

  • known in the universe.

  • And yet a third of them disappear in less than two seconds. The rest die out within

  • minutes.

  • Were they stars flaring up within our cosmic neighborhood? Or were they something far more

  • violentand more fundamental to the workings of time and space?

  • In the years that followed, a revolution would sweep the field of high-energy astronomy.

  • The Chandra X-ray Observatory was launched in 1997.

  • It was followed by the gamma ray satellites Integral in 2002, and HETE-2 in 2003.

  • The ultimate gamma ray hunter, Swift, was sent into orbit in 2004.

  • With ultra-violet, x-ray, and gamma ray sensors, Swift’s goal was to pinpoint as many as

  • 100 gamma ray bursts per year, and to relay their locations down to earth within seconds.

  • That would allow astronomers on the ground to quickly aim their telescopes at the source

  • to capture the afterglow. That would allow them to measure its distance and to find clues

  • to what caused it in the first place.

  • Those clues began to appear in early 1997. An Italian satellite called Beppo Sax detected

  • a burst and relayed its location to Earth.

  • The Hubble Space Telescope captured this image of the fading afterglow, suggesting that it

  • came from another galaxy beyond our own.

  • Astronomers analyzed light captured by ground telescopes and found hints that it was associated

  • with a supernova.

  • The association with supernovae became stronger over time.

  • A 1998 burst coincided with this supernova.

  • A 2003 burst with this supernova.

  • And a 2006 burst with this supernova.

  • But these were no ordinary explosions. Scientists were struck by the amount of energy released,

  • and by their extreme brightness.

  • On March 19, 2008, astronomers recorded a burst that originated 7.5 billion light years

  • away. And yet its afterglow was bright enough to be seen with the naked eye from Earth.

  • That confirmed a long running suspicion: that the source was a narrow and extremely powerful

  • beam of light. What astronomers saw was actually the impact of this beam as it passed through

  • clouds of gas, heating them up to billions of degrees, and generating ultra high-energy

  • gamma rays.

  • Phenomena like this are not uncommon in our universe. You can find beams and high speed

  • jets wherever matter falls rapidly into stars, galaxies, or black holes.

  • Few of these are known to marshal as much power as a gamma ray burst.

  • September 13, 2008. The Swift satellite recorded a burst with the power of 9000 supernovae,

  • and a jet that was clocked at 99.9999% the speed of light.

  • April 29, 2009 brought the second most distant object ever recorded. The journey of this

  • Gamma Ray burst started 13.14 billion years ago.

  • Astronomers have begun to see these beacons as probes for understanding the chemical evolution

  • of the cosmos, going all the way back to when stars and galaxies were just beginning to

  • form.

  • But how does nature produce a beacon of light that can reach across the entire breadth of

  • the visible universe?

  • One team of scientists has been looking for answers close to home, in a giant galaxy some

  • 50 million light years away, known as M87.

  • The Event Horizon Telescope links telescopes thousands of kilometers apart into a single

  • giant instrument. The astronomers targeted sub-millimeter radio waves because they have

  • just the right frequency to move through dust and gas in the core of M87.

  • That galaxy has one of the largest black holes known, at 6.6 billion solar masses.

  • The resolution of this system was enough to collect data on a region just outside the

  • event horizon of the black hole, the point beyond which nothing can escape its gravitational

  • pull.

  • The scientists were able to see down to the base of a spectacular jet that blasts continuously

  • out of M87’s core.

  • This region is held under the spell of extreme gravity.

  • Subject to what Albert Einstein called frame dragging, space and time are pulled along

  • on a path that leads into the black hole.

  • As gas, dust, stars or planets fall into the hole, they form into a disk that spirals in

  • with the flow of space time, reaching the speed of light just as it hits the event horizon.

  • The spinning motion of this so-calledaccretion diskcan channel some of the inflowing

  • matter out into a pair of high-energy beams, or jets.

  • How a jet can form was shown in a supercomputer simulation of a short gamma ray burst.

  • It was based on a 40-millisecond long burst recorded by Swift on May 9, 2005. It took

  • five minutes for the afterglow to fade, but that was enough for astronomers to capture

  • crucial details.

  • It had come from a giant galaxy 2.6 billion light years away, filled with old stars.

  • Scientists suspected that this was a case of two dead stars falling into a catastrophic

  • embrace.

  • Orbiting each other, they moved ever closer, gradually gaining speed.

  • At the end of the line, they began tearing each other apart, until they finally merged.

  • NASA scientists simulated the final 35 thousandths of a second, when a black hole forms.

  • As the two objects move together, their mass is scrambled into a dense, hot cloud of swirling

  • debris, shown on the left side of the image.

  • On the right, are magnetic fields that spin up off this cloud. Blue represents magnetic

  • strength a billion times greater than that of the Sun.

  • These fields begin to channel a cloud of plasma that surrounds the newly formed black hole.

  • Chaos reigns. But the new structure becomes steadily more organized, and the magnetic

  • field takes on the character of a jet.

  • Within less than a second after the black hole is born, it launches a jet of particles

  • to a speed approaching light.

  • A similar chain of events, in the death of a large star, is responsible for longer gamma

  • ray bursts.

  • Stars resist gravity by generating photons that push outward on their enormous mass.

  • But the weight of a large star’s core increases from the accumulation of heavy elements produced