It's almost a rite of passage in physics and astronomy. Scientists spend years scrounging up money to build a fantastic new instrument. Then, when the long-awaited device finally approaches completion, the panic begins: How will they handle the torrent of data?
That's the situation now, at least, with the Square Kilometer Array (SKA), a radio telescope planned for Africa and Australia that will have an unprecedented ability to deliver data -- lots of data points, with lots of details -- on the location and properties of stars, galaxies and giant clouds of hydrogen gas.
In a study published in The Astronomical Journal, a team of scientists at the University of Wisconsin-Madison has developed a new, faster approach to analyzing all that data.
Hydrogen clouds may seem less flashy than other radio telescope targets, like exploding galaxies. But hydrogen is fundamental to understanding the cosmos, as it is the most common substance in existence and also the "stuff" of stars and galaxies.
As astronomers get ready for SKA, which is expected to be fully operational in the mid-2020s, "there are all these discussions about what we are going to do with the data," says Robert Lindner, who performed the research as a postdoctoral fellow in astronomy and now works as a data scientist in the private sector. "We don't have enough servers to store the data. We don't even have enough electricity to power the servers. And nobody has a clear idea how to process this tidal wave of data so we can make sense out of it."
Lindner worked in the lab of Associate Professor Snezana Stanimirovic, who studies how hydrogen clouds form and morph into stars, in turn shaping the evolution of galaxies like our own Milky Way.
In many respects, the hydrogen data from SKA will resemble the vastly slower stream coming from existing radio telescopes. The smallest unit, or pixel, will store every bit of information about all hydrogen directly behind a tiny square in the sky. At first, it is not clear if that pixel registers one cloud of hydrogen or many -- but answering that question is the basis for knowing the actual location of all that hydrogen.
People are visually oriented and talented in making this interpretation, but interpreting each pixel requires 20 to 30 minutes of concentration using the best existing models and software. So, Lindner asks, how will astronomers interpret hydrogen data from the millions of pixels that SKA will spew? "SKA is so much more sensitive than today's radio telescopes, and so we are making it impossible to do what we have done in the past."
In the new study, Lindner and colleagues present a computational approach that solves the hydrogen location problem with just a second of computer time.
For the study, UW-Madison postdoctoral fellow Carlos Vera-Ciro helped write software that could be trained to interpret the "how many clouds behind the pixel?" problem. The software ran on a high-capacity computer network at UW-Madison called HTCondor. And "graduate student Claire Murray was our 'human,'" Lindner says. "She provided the hand-analysis for comparison."
Those comparisons showed that as the new system swallows SKA's data deluge, it will be accurate enough to replace manual processing.
Ultimately, the goal is to explore the formation of stars and galaxies, Lindner says. "We're trying to understand the initial conditions of star formation -- how, where, when do they start? How do you know a star is going to form here and not there?"
To calculate the overall evolution of the universe, cosmologists rely on crude estimates of initial conditions, Lindner says. By correlating data on hydrogen clouds in the Milky Way with ongoing star formation, data from the new radio telescopes will support real numbers that can be entered into the cosmological models.
"We are looking at the Milky Way, because that's what we can study in the greatest detail," Lindner says, "but when astronomers study extremely distant parts of the universe, they need to assume certain things about gas and star formation, and the Milky Way is the only place we can get good numbers on that."
With automated data processing, "suddenly we are not time-limited," Lindner says. "Let's take the whole survey from SKA. Even if each pixel is not quite as precise, maybe, as a human calculation, we can do a thousand or a million times more pixels, and so that averages out in our favor."
Robert Lindner | EurekAlert!
Tangled magnetic fields power cosmic particle accelerators
14.12.2018 | DOE/SLAC National Accelerator Laboratory
In search of missing worlds, Hubble finds a fast evaporating exoplanet
14.12.2018 | NASA/Goddard Space Flight Center
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
14.12.2018 | Power and Electrical Engineering
14.12.2018 | Physics and Astronomy
14.12.2018 | Physics and Astronomy