When Will Time End?

The answer to this question may depend on whether Stephen Hawking was right in his theory that describes how black holes shed mass and eventually decay. Time is flying by on this busy, crowded planet as life changes and evolves from second to second. At the same time, the arc of the human lifespan is getting longer: 67 years is the global average, up from just 20 years in the Stone Age.

Modern science provides a humbling perspective. Our lives, indeed even that of the human species, are just a blip compared to the Earth, at 4.5 billion years and counting, and the universe, at 13.7 billion years.

It now appears the entire cosmos is living on borrowed time. It may be a blip within a much grander sweep of time. When, we now ask, will time end?

Our lives are governed by cycles of waking and sleeping, the seasons, birth and death. Understanding time in cyclical terms connects us to the natural world, but it does not answer the questions of science.

What explains Earth’s past, its geological eras and its ancient creatures? And where did our world come from? How and when will it end? In the revolutions spawned by Copernicus Continue reading When Will Time End?

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The Most Powerful Objects in the Universe

All across the immense reaches of time and space, energy is being exchanged, transferred, released, in a great cosmic pinball game we call our universe.

How does energy stitch the cosmos together, and how do we fit within it? We now climb the power scales of the universe, from atoms, nearly frozen to stillness, to Earth’s largest explosions. From stars, colliding, exploding, to distant realms so strange and violent they challenge our imaginations. Where will we find the most powerful objects in the universe?

Today, energy is very much on our minds as we search for ways to power our civilization and serve the needs of our citizens. But what is energy? Where does it come from? And where do we stand within the great power streams that shape time and space?

Energy comes from a Greek word for activity or working. In physics, it’s simply the property or the state of anything in our universe that allows it to do work. Whether it’s thermal, kinetic, electro-magnetic, chemical, or gravitational.

The 19th century German scientist Hermann von Helmholtz found that all forms of energy are equivalent, that one form can be transformed into any other. The laws of physics say that in a Continue reading The Most Powerful Objects in the Universe

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The Largest Black Holes in the Universe

Our Milky Way may harbor millions of black holes… the ultra dense remnants of dead stars. But now, in the universe far beyond our galaxy, there’s evidence of something far more ominous. A breed of black holes that has reached incomprehensible size and destructive power. Just how large, and violent, and strange can they get?

A new era in astronomy has revealed a universe long hidden to us. High-tech instruments sent into space have been tuned to sense high-energy forms of light — x-rays and gamma rays — that are invisible to our eyes and do not penetrate our atmosphere. On the ground, precision telescopes are equipped with technologies that allow them to cancel out the blurring effects of the atmosphere. They are peering into the far reaches of the universe, and into distant caldrons of light and energy. In some distant galaxies, astronomers are now finding evidence that space and time are being shattered by eruptions so vast they boggle the mind.

We are just beginning to understand the impact these outbursts have had on the universe: On the shapes of galaxies, the spread of elements that make up stars and planets, and ultimately the very existence of Earth. The discovery Continue reading The Largest Black Holes in the Universe

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Black Hole Merger Simulation

From NASA’s Scientific Visualization Studio. Supercomputer models of merging black holes reveal properties that are crucial to understanding future detections of gravitational waves. This movie follows two orbiting black holes and their accretion disk during their final three orbits and ultimate merger. Redder colors correspond to higher gas densities.

The initial magnetic field of the gas is amplified by 100 times. Magnetic fields evacuate the region above the black hole and produce a thinner, hotter, denser disk in the immediate vicinity of the black hole than in simulations without them. The merged black hole resides within a hot, dense disk of ionized gas. The base of the low-density funnel is visible near the center. Such a structure could support a jet of particles moving near the speed of light, although one was not yet produced before the simulation ended. This model, which includes the effects of general relativity, magnetic fields and gas dynamics, produced an electromagnetic signal 10,000 brighter than in simulations that ignored the gas effects.

The sequence ends with a simulation of the merger of two black holes and the resulting emission of gravitational radiation. The colored fields represent a component of the curvature of space-time. The outer red sheets Continue reading Black Hole Merger Simulation

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Curiosity Finds River Rocks and River Beds on Mars

NASA’s Curiosity rover mission has found evidence a stream once flowed across the area on Mars where the rover is driving. There is earlier evidence for the presence of water on Mars, but this evidence — images of rocks containing ancient streambed gravels — is the first of its kind. Scientists are studying the images of stones cemented into a layer of conglomerate rock. The sizes and shapes of stones offer clues to the speed and distance of a long-ago stream’s flow.

The sizes and shapes of stones offer clues to the speed and distance of a long-ago stream’s flow. “From the size of gravels it carried, we can interpret the water was moving about 3 feet per second, with a depth somewhere between ankle and hip deep,” said Curiosity science co-investigator William Dietrich of the University of California, Berkeley. “Plenty of papers have been written about channels on Mars with many different hypotheses about the flows in them. This is the first time we’re actually seeing water-transported gravel on Mars. This is a transition from speculation about the size of streambed material to direct observation of it.”

The finding site lies between the north rim of Gale Continue reading Curiosity Finds River Rocks and River Beds on Mars

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Giant Telescopes of the Future

Astronomy is big science. It’s a vast Universe out there, and the exploration of the cosmos requires huge instruments.

This is the 5-meter Hale reflector on Palomar Mountain. When the European Southern Observatory came into being, fifty years ago, it was the largest telescope in the world.

ESO’s Very Large Telescope at Cerro Paranal is the state of the art now. As the most powerful observatory in history, it has revealed the full splendor of the Universe in which we live.

But astronomers have set their sights on even bigger instruments.
And ESO is realizing their dreams.

San Pedro de Atacama. Tucked amidst breathtaking scenery and natural wonders, this picturesque town is home to indigenous Atacameños and adventurous backpackers alike.

Not far from San Pedro, ESO’s first dream machine is taking shape.
It’s called ALMA — the Atacama Large Millimeter/submillimeter Array.

Close together, the 66 antennas provide a wide-angle view. But spread apart, they reveal much finer detail over a smaller area of sky.

At submillimeter wavelengths, ALMA sees the Universe in a different light. But what will it reveal?

The birth of the very first galaxies in the Universe, in the wake of the Big Bang.

Cold and Continue reading Giant Telescopes of the Future

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Astronomers Spot Sudden Black Hole Flare Up

Astronomers using NASA’s Swift satellite recently detected a rise in high-energy X-rays from a source toward the center of our Milky Way galaxy. The outburst, produced by a rare X-ray nova, came from a previously unknown stellar-mass black hole.

An X-ray nova is a short-lived X-ray source that appears suddenly, reaches its emission peak in a few days and then fades out over a period of months. The outburst arises when a torrent of stored gas suddenly rushes toward one of the most compact objects known, either a neutron star or a black hole.

The rapidly brightening source triggered Swift’s Burst Alert Telescope twice on the morning of Sept. 16, and once again the next day. Named Swift J1745-26 after the coordinates of its sky position, the nova is located a few degrees from the center of our galaxy toward the constellation Sagittarius. While astronomers do not know its
precise distance, they think the object resides about 20,000 to 30,000 light-years away in the galaxy’s inner region.

Ground-based observatories detected infrared and radio emissions, but thick clouds of obscuring dust have prevented astronomers from catching Swift J1745-26 in visible light.

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Battle of Giant Windy Stars

From NASA’s legendary Scientific Visualization Studio, here’s news of one of the nearest and richest stellar associations in our galaxy. Cygnus OB2, located about 4,700 light-years away, hosts some 3,000 hot stars, including about 100 in the O class. Weighing in at more than a dozen times the sun’s mass and sporting surface temperatures five to ten times hotter, these ginormous blue-white stars blast their surroundings with intense ultraviolet light and powerful outflows called stellar winds.

Two of these stars can be found in the intriguing binary system known as Cygnus OB2 #9. In 2011, NASA’s Swift satellite, the European Space Agency’s XMM-Newton observatory and several ground-based facilities took part in a campaign to monitor the system as the giant stars raced toward their closest approach. The observations are giving astronomers a more detailed picture of the stars, their orbits and the interaction of their stellar winds.

An O-type star is so luminous that the pressure of its starlight actually drives material from its surface, creating particle outflows with speeds of several million miles an hour. Put two of these humongous stars in the same system and their winds can collide during all or part of the orbit, creating both radio emission Continue reading Battle of Giant Windy Stars

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Why Mars Died, and Earth Lived

This video explores the most basic question of all: why we explore space? Be sure to experience the visual spectacle in full HD, 1080P.

The Mars rover, Curiosity, is the latest in a long line of missions to Mars: landers sent to scoop its soil and study its rocks, orbiters sent to map its valleys and ridges.

They are all asking the same question. Did liquid water once flow on this dry and dusty world? Did it support life in any form? And are there remnants left to find? The science that comes out of these missions may help answer a much larger, more philosophical question.

Is our planet Earth the norm, in a galaxy run through with life-bearing planets? Or is Earth a rare gem, with a unique make-up and history that allowed it to give rise to living things? On Mars, Curiosity has spotted pebbles and other rocks commonly associated with flowing water.

It found them down stream on what appears to be an ancient river fan, where water flowed down into Gale Crater. This shows that at some point in the past, Mars had an atmosphere, cloudy skies, and liquid water flowing. So what could have turned it into the Continue reading Why Mars Died, and Earth Lived

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Light from the Core of the Sun

These exquisite images are a must see at full resolution. Space imagery from NASA’s Conceptual Image Lab. An elegant interaction powers the sun, producing the light and energy that makes life possible. That interaction is called fusion, and it naturally occurs when two atoms are heated and compressed so intensely that their nuclei merge into a new element. This process often leads to the creation of a photon, the particles of light that are released from the sun.

However, before exiting our star, each photon must first undergo a long journey. Over the course of 40,000 years it will be absorbed by other atoms and emitted repeatedly until reaching the sun’s surface. Once there, the photons stream out, illuminating Earth, the solar system and beyond. The number released from the surface every second is so vast that it is more than a billion billion times greater than the number of grains of sand on our planet.

This movie takes us on a space weather journey from the center of the sun to solar eruptions in the sun’s atmosphere all the way to the effects of that activity near Earth. The view starts in the core of the sun where atoms fuse Continue reading Light from the Core of the Sun

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