Record-Breaker! Heftiest and Purest 'Failed Star' Identified

Artist's illustration of the newfound brown dwarf SDSS J0104+1535, which is 90 times more massive than Jupiter. The object is the most massive and purest "failed star" known, researchers said.

Credit: John Pinfield

An ancient brown dwarf is the most massive and purest such "failed star" ever discovered, a new study suggests.

Researchers studied an object called SDSS J0104+1535, which lies about 750 light-years from Earth in the Milky Way's "halo," a population of extremely old stars above the galaxy's familiar spiral disk.

SDSS J0104+1535 is a brown dwarf — a bizarre, gaseous body larger than a planet but too small to sustain the nuclear fusion reactions that power stars. New observations by the European Southern Observatory's Very Large Telescope in Chile provide new details about this object, which astronomers think is 10 billion years old. [The Strangest Things in Space]

For example, study team members said, SDSS J0104+1535 is about 90 times more massive than Jupiter, making it the heaviest known brown dwarf. (For perspective: The sun is 1,050 times more massive than Jupiter. And Jupiter is 318 times more massive than Earth.)

In addition, just 0.01 percent of SDSS J0104+1535 consists of elements other than hydrogen and helium — meaning that the body is 250 times purer than the sun, and the purest brown dwarf ever observed.

"Pure" in this sense refers to the stuff originally present just after the Big Bang that created the universe 13.82 billion years ago — mostly hydrogen and helium, along with small amounts of lithium. All the naturally occurring elements heavier than these three were created inside stars over the eons.

"We really didn't expect to see brown dwarfs that are this pure," study lead author ZengHua Zhang, of the Institute of Astrophysics in the Canary Islands, said in a statement. "Having found one, though, often suggests a much larger hitherto undiscovered population. I'd be very surprised if there aren't many more similar objects out there waiting to be found."

The new study has been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society. You can read it for free at the online preprint site arXiv.org.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us@Spacedotcom, Facebook or Google+. Originally published on Space.com.

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Rugged Antarctica Shows Its Ice in New 3D Map

Scientists have created a 3D view of Antarctica by combining 250 million measurements taken by the European Space Agency's CryoSat mission between 2010 and 2016.

Credit: CPOM 

A new three-dimensional view of Antarctica shows off the southernmost continent in all of its rugged glory.

Created by satellite data collected by the European Space Agency's CryoSat, the map can be downloaded at a University of Leeds websiteand will soon be hosted at the portal for the United Kingdom's Center for Polar Observation and Modelling (CPOM).

"We used around 250 million measurements taken by CryoSat between 2010 and 2016 to create the most comprehensive picture of Antarctic ice elevation currently available," Tom Slater, a researcher at the center,said in a statement. 

Measuring the ice

CryoSat uses radar altimeter to measure ice-sheet thickness at the North and South Poles. This method involves beaming radio waves toward the ground from a satellite and measuring the time it takes for the reflected waves to bounce back. The instrument aboard the CryoSat satellite is the first of its kind designed for monitoring ice, according to the ESA; it can also measure sea level. [Images of Melt: Earth's Vanishing Ice]    

The ESA's CryoSat mission has delivered a detailed map of the height of the Antarctic ice sheet with a resolution of about 1.2 miles (2 kilometers).

Credit: CPOM

The measurements are useful to scientists who are trying to understand changes in the Antarctic ice sheet, including where increased snowfall is causing accumulating ice and where melting and iceberg calving are causing ice losses.

"This should benefit not only studies of the Antarctic ice sheet, but also projections of future sea-level rise," Andrew Shepherd, the director of CPOM, said in a statement.

Antarctic in flux

As the climate warms, Antarctica's ice is changing. In 2002, the Larsen B ice shelf collapsed spectacularly, and a massive rift in the Larsen C ice shelf is threatening to do the same to that floating ice. When floating ice shelves collapse, they do not raise sea levels by themselves, but their loss does remove a barrier to the flow of land-based ice into the oceans.

Scientists have observed a trend toward melting on the land-based West Antarctica ice sheet in recent years, according to the National Snow and Ice Data Center. The data from East Antarctica has been trickier to interpret, with some research finding that the region was adding ice because of increased snowfall. (Warm air can hold more moisture, so as the globe warms, precipitation might increase in some areas.) Because of the balancing act between ice loss in the west and ice gains in the east, there has been a long-running scientific controversy over whether the continent as a whole is losing or gaining ice.

Alarmingly, field scientists recently discovered huge craters called moulins on East Antarctica's Roi Baudouin ice shelf. The melt features had never been seen before on an ice shelf. Research published in the journal Nature Climate Change in December 2016 on the moulins and new satellite data found that East Antartica may be more vulnerable to melt than previously believed.

Artical Copy By: Live Science.

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