The new movie "Interstellar" explores a longstanding fascination, but UA astrophysicists are using cutting-edge technology to go one better. They're working on how to take pictures of the black hole at the center of the galaxy.
What does a black hole look like up close?
When the sci-fi movie "Interstellar" — hitting theaters this week — wows audiences with its computer-generated views of one of most enigmatic and fascinating phenomena in the universe, University of Arizona astrophysicists Chi-kwan Chan, Dimitrios Psaltis and Feryal Ozel are likely to nod appreciatively and say something like, "Meh, that looks nice, but check out what we've got."
"We want to know what happens near extremely compact objects such as black holes and neutron stars," said Psaltis, a professor of astronomy and physics in the UA's Department of Astronomy and Steward Observatory. "We want to watch as matter fed onto a black hole crosses the event horizon, the point of no return, and disappears."
To find answers, the group created a monster in the basement of the UA's high-performance computing facility. Harnessing the power of the UA's new supercomputer — nicknamed El Gato — the researchers combined knowledge from mathematical equations and astronomical observations to generate visualizations of an object known by astronomers as Sagittarius A* ("Sagittarius A star"), a supermassive black hole comprising the mass of 4.3 million suns.
Located 26,000 light-years from Earth at the center of our galaxy, Sagittarius A* is tiny to the eyes of astronomers. Smaller than Mercury’s orbit around the sun, it appears about the same size as a grapefruit on the moon.
The team just published the first major science results obtained using El Gato's unique, massive, parallel-computing capabilities to create visualizations of what a space traveler might see upon approaching SgrA*. The results, published in two reports in the Astrophysical Journal — one focusing on the imaging and the other on the computing — provide some of the groundwork for the Event Horizon Telescope, or EHT, a huge undertaking involving scientists and observatories around the world to take the first-ever picture of SgrA*.
The film "Interstellar," starring Matthew McConaughey and Anne Hathaway, prominently features a black hole, touted as the first visual depictions based on the actual science and mathematics of Einstein's Theory of General Relativity. On some of the renderings, a special-effects team of about 30 experts reportedly spent up to 100 hours of running calculations to create each frame.
"Our team of four here at the UA can produce visuals of a black hole that are more scientifically accurate in a few seconds," said Ozel, also a professor of astronomy and physics at Steward Observatory.
"It's a bit like gaming on steroids," she explained. "El Gato uses a massively parallel architecture of hundreds of graphic processors working side by side, with each node functioning as a renderer in real time."
As part of a collaboration that includes the papers' first author, postdoctoral fellow Chan, and researchers at Harvard University and MIT, the husband-and-wife research team of Psaltis and Ozel developed software algorithms capable of calculating the paths of millions of individual photons in mere seconds as they shoot toward the black hole.
Funded by the National Science Foundation and NASA, the computer simulations are a crucial step before astronomers can start to look for the black hole using the EHT, functioning as a sort of field ID guide of what astronomers should look for once the EHT is up and running.
The EHT will combine radio telescopes across the globe to create a virtual telescope the size of the Earth. These include the UA's Arizona Radio Observatory as well as the South Pole Telescope, outfitted with new receivers built by a group led by UA assistant professor of astronomy Daniel Marrone.
"We wouldn't be able to observe a black hole against a black sky," Ozel said. "Therefore, we look for other telltale signatures telling us about the presence of a black hole."
The gravitational field around a black hole is so immense that it swallows everything in its reach. Not even light can escape its grip. For that reason, black holes are just that: They emit no light whatsoever, and their “nothingness” blends into the black void of the universe.
As matter comes under the black hole's spell of extreme gravity, a cosmic traffic jam ensues, in which gas swirls around it like water circling a drain. As matter compresses, the resulting friction turns it into plasma heated to a billion degrees or more, causing it to "glow" — and radiate energy that astronomers can detect here on Earth.
"Our visualizations show there is a place where photons linger and form a ring outlining the shadow of the black hole," Psaltis said. "That ring of light makes the black hole easier to find than if we were looking for complete blackness. These simulations also help us find ways to distinguish this signature from all this swirling plasma around the black hole."
By imaging the glow of matter swirling around the black hole before it goes over the edge and plunges into the abyss of space and time, scientists can see only the outline of the black hole, also called its shadow.
In addition to providing groundwork for the EHT, the simulations will support NICER, a new NASA mission involving an instrument that will be attached to the International Space Station, to help scientists better understand neutron stars and to test navigation methods for future spacecraft using neutron stars as extremely accurate clocks.
Until EHT is ready to take the first images of what lurks at the center of our Milky Way, astrophysicists will have to get by with gaming on steroids — or going to the movies.
email@example.com(link sends e-mail)
Daniel Stolte | UANews
Taking a spin on plasma space tornadoes with NASA observations
20.11.2017 | NASA/Goddard Space Flight Center
NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
20.11.2017 | Earth Sciences
20.11.2017 | Earth Sciences
20.11.2017 | Life Sciences