astrophysical phenomena

IceCube helps demystify strange radio bursts from deep space

For a decade, astronomers have puzzled over ephemeral but incredibly powerful radio bursts from space.

The phenomena, known as fast radio bursts or FRBs, were first detected in 2007 by astronomers scouring archival data from Australia’s Parkes Telescope, a 64-meter diameter dish best known for its role receiving live televison images from the Apollo 11 moon landing in 1969.

But the antenna’s detection of the first FRB – and the subsequent confirmed discovery of nearly two dozen more powerful radio pulses across the sky by Parkes and other radio telsescopes – has sent astrophysicists scurrying to find more of the objects and to explain them.

“It’s a new class of astronomical events. We know very little about FRBs in general,” explains Justin Vandenbroucke, a University of Wisconsin-Madison physicist who, with his colleagues, is turning IceCube, the world’s most sensitive neutrino telescope, to the task of helping demystify the powerful pulses of radio energy generated up to billions of light-years from Earth.

The idea, the Wisconsin physicist says, is to see if high-energy neutrinos are generated coincident with FRBs. If that’s the case, it would give scientists leads to what might be generating the powerful radio flares and reveal something about the physics of the environments where they are generated.

IceCube is a neutrino detector composed of 5,160 optical modules embedded in a gigaton of crystal-clear ice a mile beneath the geographic South Pole. Supported by the National Science Foundation, IceCube is capable of capturing the fleeting signatures of high-energy neutrinos – nearly massless particles generated, presumably, by dense, violent objects such as supermassive black holes, galaxy clusters, and the energetic cores of star-forming galaxies.

The catch with fast radio bursts, notes Vandenbroucke, is that they are mostly random and they last for only a few milliseconds, too fast to routinely detect or conduct follow-up observations with radio and optical telescopes. Only one FRB has been found to repeat, an object known as FRB 121102 in a galaxy about 3 billion light-years away. A key advantage of IceCube is the telescope’s extremely wide field of view compared to optical and radio telescopes. The telescope gathers data on neutrino events as the particles crash through the Earth, and it sees the entire sky in both the southern and northern hemispheres.

That means if an FRB is detected by any of the world’s radio telescopes, Vandenbroucke and his team can analyze IceCube data for that region of the sky at the time the radio pulse was detected.

Observing a fast radio burst in conjunction with neutrinos would be a coup, helping establish source objects for both types of phenomena. “Astrophysical neutrinos and fast radio bursts are two of the most exciting mysteries in physics today,” says Vandenbroucke. “There may be a link between them.”

So far, Vandenbroucke and his team have looked at nearly 30 FRBs, including 17 bursts from the “repeater,” FRB 121102.

The UW team’s first look, however, did not detect neutrino emission with any of the FRBs identified in IceCube’s archival data. Not seeing neutrinos in concert with any of the FRBs studied so far gives scientists an upper limit on the amount of neutrino emission that could occur in a burst.

“We can say that the amount of energy emitted by each burst as neutrinos is less than a certain amount, which can then be compared to predictions from individual theories,” Vandenbroucke explains. “As the number of bursts is expected to grow dramatically in the next couple years, these constraints will become even stronger – or we will make a detection.”

Bright or very high-energy neutrinos would be characteristic of certain classes of astronomical objects. “We’ve ruled out gamma-ray bursts and we’ve strongly constrained the possibility of black holes” as neutrino sources, says Vandenbroucke. His team’s analysis of four FRB events was published in the August 2017 Astrophysical Journal. “There could be even more exotic physics going on.”

Scientists believe FRBs occur much more frequently than they have been observed. Some estimate that there are as many as 10,000 FRB events per day coming from all directions in the sky. And with astronomers now on the lookout for the starnge pulses of radio energy, Vandenbroucke expects the pace of discovery to accelerate as the world’s radio telescopes continue their searches and as new radio interferometers come on line.

IMAGE….IceCube is a neutrino detector composed of 5,160 optical modules embedded in a gigaton of crystal-clear ice a mile beneath the geographic South Pole. PHOTO COURTESY OF NATIONAL SCIENCE FOUNDATION

anonymous asked:

Would you ever write a fic about Bill being dormant in Stan's mind and giving him nightmares or something? I love the idea and I think you would do an amazing job :)

Flattery will get you everywhere, anon. Then again, who are we kidding, I was looking for an excuse to write this. Sorry it took a bit, but here we are! 


Echoes

Even after he fell asleep, the adventure was far from over.

Sailing the ocean on a ship with his brother was a dream come true, but even when he closed his eyes after a long day of kraken-punching and fish-reeling, the journey continued. At least for Stan, who had a lot of ground left to cover, memory wise. 

The map of his mindscape was different now, Stan knew. Of course, it had shifted and reshaped throughout the course of his life, as seamless and upheaving a process as the act of growing up. It changed as he changed, gained when he gained, lost when he was – and not too long ago, crumbled with his sacrifice. But the remnants had risen from the ashes, reclaimed from the void by those he loved, and so his mind had rebuilt accordingly.

Currently, it took the shape of the Stan o’ War II, and from the deck where he stood he had a view of a vast sea of black, swirling waves. He had fallen overboard a more than once, and the water had not been such a pretty sight as he drowned beneath the darkness, but there had always been a voice to tug him back towards the safety of the surface, usually his brother or the twins or Soos.

Below the deck was where the true mysteries lay, waiting behind halls upon halls of doors. Stanley Pines had been a man of secrets, who kept much hidden beneath the surface, although he was finding it easier to open up nowadays, and letting the light shine where before it had never been allowed to touch.

Keep reading

Decompressed is inspired by Problem Sleuth and cult hit videogame Space Station 13. MS Paint Adventures meets Star Trek somewhere near Sealab 2021. It is currently concluding Sector 1, the prologue chapter of its story, and will be hitting the road quite soon.

It’s the spacefuture, and you are a hapless background greyshirt Staff Assistant in the brig of a space station. As is to be expected, you intend to escape the brig and leave the space station. This involves getting around mind-controlling aliens, incompetent security, structural hazards, dangerous astrophysical phenomena, shapeshifting biohorrors, mutinous crew, cults, and ruthless mercenaries from enemy corporations.

And that’s assuming you can overcome your own laziness, lacking charisma, and poor attention span to get out of the brig in the first place. Baby steps, everyone has to start somewhere.

Read it here.

bbc.com
The hunt for Albert Einstein's missing waves
In the Italian countryside, not far from Pisa, a vast experiment is about to get under way to find the last great proof of Einstein's theory of gravity.

In the Italian countryside, not far from Pisa, a vast experiment is about to be switched on.

If it’s a success, one of Albert Einstein’s greatest predictions will have been directly observed for the first time.

If it fails, laws of physics might have to be reconsidered.

The experiment is called Advanced Virgo, and it will be hunting for the most elusive of astrophysical phenomena.

“Maybe we have the opportunity for the first time to detect gravitational waves on the Earth,” explains Dr Franco Frasconi, from the University Pisa, who is part of Virgo’s international team.

“This would be a clear demonstration that what [Einstein] said 100 years ago is absolutely correct.”

Continue Reading.

Exploring the Dark Universe

As of this week, the Hayden Planetarium’s Space Theater, which has been closed for renovations since mid-August, is open again, and we’ve made a few improvements you won’t want to miss, including refurbished seats and a state-of-the-art new seamless screen.

The reopened theater is coming back with a bang—the Big Bang, in fact, as the Museum’s latest Space Show, Dark Universe, returns to view. In Dark Universe, astrophysicist and Frederick P. Rose Director of the Hayden Planetarium Neil deGrasse Tyson is your guide on a trip through space and time. The destination: two recently discovered, and still mysterious, phenomena in astrophysics—dark matter and dark energy. Finding out more about dark energy and dark matter is key to understanding the nature of the world we live in. 

Need to brush up on dark energy and dark matter? We’ve got the video series for you. Below, Dr. Mordecai Mac Low offers an overview of dark matter, reveals what we know about the mysterious phenomenon of dark energy, and discusses cosmic microwave background, energy left over from the Big Bang that provides a “baby picture of the universe.”

Now you’re ready! Get tickets to Dark Universe today. 

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As of today, the Hayden Planetarium Space Theater, which has been closed for renovations since mid-August, is open again, and we’ve made a few improvements you won’t want to miss. 

While the updates include new carpet and refurbished seats, the main attraction in the 429-seat theater is a state-of-the-art new screen that ensures the Hayden Planetarium’s award-winning Space Shows are displayed to their full advantage.

The Space Theater’s last screen, which was installed in 2000, was a limiting optical factor for the dome, says Director of Rose Center Engineering Benjy Bernhardt. That was due to the small but noticeable seams that held it together. The new screen is built from thin sheets of aluminum and coated with powder to give it a startling white hue that makes it an ideal backdrop for planetarium projections. It is also held together by invisible “nanoseams” that make each of the pieces flush with one another, rather than overlapping. That means that when a projection is shown on the dome, the seams disappear entirely, creating a fuller sense of reality and immersion for viewers.

While the theater’s doors have been closed for the installation of the new screen, other upgrades have been going in too, all supported by the Charles Hayden Foundation. A new LED lighting system has been installed to cut heat generation and energy costs for lighting the dome, and the projector is getting an update as well.

The reopened theater is coming back with a bang—the Big Bang, in fact, as The Museum’s latest Space Show, Dark Universe, returns to view. In Dark Universe, astrophysicist and Frederick P. Rose Director of the Hayden Planetarium Neil deGrasse Tyson is your guide on a trip through space and time, from the Big Bang to a telescope in modern-day California. The destination: two recently discovered, and still mysterious, phenomena in astrophysics—dark matter and dark energy. Finding out more about dark energy and dark matter is key to understanding the nature of the world we live in.

In stunning scenes based on scientific data—including a NASA probe’s breathtaking plunge into Jupiter’s atmosphere and groundbreaking visualizations of unobservable dark matter—Dark Universe explores this new age of cosmic discovery and reveals the mysteries that have been brought to light so far.

Get tickets for Dark Universe today!