ThinkStock
ThinkStock

The Mystery of the "Space Roar"

ThinkStock
ThinkStock

In 2009, scientists at NASA's Goddard Space Flight Center sent a machine called ARCADE into space on a giant balloon, in search of radiation from the universe's earliest stars. ARCADE (Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission) carried seven sensors that picked up electromagnetic radiation like radio waves. The plan was to lift it far enough up to prevent the Earth's atmosphere from interfering. Then, the finely-tuned instrument could detect faint radio signals from ancient stars.

Instead, ARCADE detected a huge amount of radio noise—six times louder than scientists had predicted—which has since come to be known as the "space roar." And while there are some theories, we still don't know what's causing it.

Space Sounds

Of course, space isn't roaring in any way that our ears could hear. But there are objects in the universe—including some galaxies—which emit radio waves via synchrotron radiation.

According to Dale Fixsen, a University of Maryland research scientist and a member of the ARCADE team, NASA had built devices that detected radio noise before. These worked by looking at one point in the sky, and then at another nearby one for contrast. These instruments were useful for detecting radio-emitting galaxies and supernovas, because they measured the difference between two points. But they couldn't detect the roar.

"If there's a uniform source [of synchrotron radiation], those instruments are blind to it," Fixsen tells mental_floss.

On the other hand, ARCADE used a "large beam" that searched 7 percent of the sky. Because of the large area it searched, and its high-precision sensors, it was the first instrument we've built that could discover the roar.

But it couldn't find out everything. Fixsen says that synchrotron radiation has a characteristic spectrum. And since every source of the radiation displays this same spectrum, ARCADE couldn't discover what was roaring.

Roar Theories

Fixsen says that synchrotron radiation usually comes hand in hand with infrared radiation. We've already measured the amount of infrared radiation that the Milky Way emits with the COBE satellite, and according to Fixsen, with our galaxy's level of infrared, it doesn't look like the Milky Way is the source of the synchrotron radiation for the "space roar."

"The relationship is tight for all galaxies we've measured," Fixsen says. "It should hold true for our galaxy as well."

On the other hand, theorists think that we've detected almost all the sources of this radiation outside our galaxy. And we know that none of these sources is causing the "roar."

According to Fixsen, there are a few possible explanations. First, the "roar" could be coming from the earliest stars. The first stars didn't have any dust—because the first dust in the universe was formed within those stars. This could have let those stars create a lot of synchrotron radiation, without a correspondingly high amount of infrared.

Second, the radiation might be coming from gases in large clusters of galaxies—Fixsen says that it would be difficult for the instruments we've used up until now to detect radiation from these.

Third, it could be coming from dim, but extremely plentiful, radio galaxies. Individually, they would be too quiet for us to detect, but en masse they might be loud enough to create the "roar."

Future plans

But while there are some plausible theories, we still don't have any data to tell us which one is right. Fixsen says that there's been talk about flying ARCADE again (it's currently living in the Goddard Space Flight Center). Or they might use an instrument on the ground next time; Fixsen says they could use the data from the ARCADE mission to calibrate it, and avoid interference from the atmosphere.

But for now, what NASA wrote in its 2009 press release is still true: "The source of this cosmic radio background remains a mystery."

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Frederick M. Brown, Getty Images
Stephen Hawking’s Memorial Will Beam His Words Toward the Nearest Black Hole
Frederick M. Brown, Getty Images
Frederick M. Brown, Getty Images

An upcoming memorial for Stephen Hawking is going to be out of this world. The late physicist’s words, set to music, will be broadcast by satellite toward the nearest black hole during a June 15 service in the UK, the BBC reports.

During his lifetime, Hawking signed up to travel to space on Richard Branson’s Virgin Galactic spaceship, but he died before he ever got the chance. (He passed away in March.) Hawking’s daughter Lucy told the BBC that the memorial's musical tribute is a “beautiful and symbolic gesture that creates a link between our father's presence on this planet, his wish to go into space, and his explorations of the universe in his mind.” She described it as "a message of peace and hope, about unity and the need for us to live together in harmony on this planet."

Titled “The Stephen Hawking Tribute,” the music was written by Greek composer Vangelis, who created the scores for Blade Runner and Chariots of Fire. It will play while Hawking’s ashes are interred at Westminster Abbey, near where Isaac Newton and Charles Darwin are buried, according to Cambridge News. After the service, the piece will be beamed into space from the European Space Agency’s Cebreros Station in Spain. The target is a black hole called 1A 0620-00, “which lives in a binary system with a fairly ordinary orange dwarf star,” according to Lucy Hawking.

Hawking wasn't the first person to predict the existence of black holes (Albert Einstein's general theory of relativity accounted for them back in the early 1900s), but he spoke at length about them throughout his career and devised mathematical theorems that gave credence to their existence in the universe.

Actor Benedict Cumberbatch, a friend of the Hawking family who portrayed the late scientist in the BBC film Hawking, will speak at the service. In addition to Hawking's close friends and family, British astronaut Tim Peake and several local students with disabilities have also been invited to attend.

[h/t BBC]

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IKEA
IKEA's New Collection for Tiny Apartments Is Inspired by Life on Mars
IKEA
IKEA

Living in a city apartment can feel claustrophobic at times. As Co.Design reports, the Swedish furniture brand IKEA took this experience to the extreme when designers visited a simulated Mars habitat as research for their latest line of housewares aimed at urbanites.

The new collection, called Rumtid, is tailored to fit the cramped spaces that many people are forced to settle for when apartment-hunting in dense, expensive cities. The designers knew they wanted to prioritize efficiency and functionality with their new project, and Mars research provided the perfect inspiration.

At the Mars Society's Mars Desert Research Station in Utah, scientists are figuring out how to meet the needs of potential Mars astronauts with very limited resources. Materials have to be light, so that they require as little rocket fuel as possible to ferry them to the red planet, and should ideally run on renewable energy.

IKEA's designers aren't facing quite as many challenges, but spending a few days at the simulated Martian habitat in Utah got them thinking on the right track. The team also conducted additional research at the famously snug capsule hotels in Tokyo. The Rumtid products they came up with include an indoor terrarium shaped like a space-age rocket, a set of colorful, compact air purifiers, and light-weight joints and bars that can be snapped into modular furniture.

The collection isn't ready to hit IKEA shelves just yet—the chain plans to make Rumtid available for customers by 2020. In the meantime, the designers hope to experiment with additional science fiction-worthy ideas, including curtains that clean the air around them.

Air purifiers designed for urban living.

Furniture joints on bubble wrap on black table.

Modular furniture holding water bag.

[h/t Co.Design]

All images courtesy of IKEA.

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