Water discovered for first time in atmosphere of habitable exoplanet

Until the late 20th century, astronomers had only identified the planets in our own solar system. But everything changed in 1995, when the discovery of the first exoplanet orbiting a Sun-like star was confirmed. Videographic on exoplanets. (AFP)
Updated 12 September 2019
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Water discovered for first time in atmosphere of habitable exoplanet

  • Water is crucial in the search for life, in part because it carries oxygen

PARIS: Water has been discovered for the first time in the atmosphere of an exoplanet with Earth-like temperatures that could support life as we know it, scientists revealed Wednesday.
Eight times the mass of Earth and twice as big, K2-18b orbits in its star’s “habitable zone” at a distance — neither too far nor too close — where water can exist in liquid form, they reported in the journal Nature Astronomy.
“This planet is the best candidate we have outside our solar system” in the search for signs of life, co-author Giovanna Tinetti, an astronomer at University College London, told AFP.
“We cannot assume that it has oceans on the surface but it is a real possibility.”
Of the more than 4,000 exoplanets detected to date, this is the first known to combine a rocky surface and an atmosphere with water.
Most exoplanets with atmospheres are giant balls of gas, and the handful of rocky planets for which data is available seem to have no atmosphere at all.
Even if they did, most Earth-like planets are too far from their stars to have liquid water or so close that any H2O has evaporated.
Discovered in 2015, K2-18b is one of hundreds of so-called “super-Earths” — planets with less than ten times the mass of ours — spotted by NASA’s Kepler spacecraft.
Future space missions are expected to detect hundreds more in the coming decades.

“Finding water in a potentially habitable world other than Earth is incredibly exciting,” said lead-author Angelos Tsiaras, also from UCL.
“K2-18b is not ‘Earth 2.0’,” he said. “However, it brings us closer to answering the fundamental question: is the Earth unique?“
Working with spectroscopic data captured in 2016 and 2017 by the Hubble Space Telescope, Tsiaras and his team used open-source algorithms to analyze the starlight filtered through K2-18b’s atmosphere.
They found the unmistakable signature of water vapor. Exactly how much remains uncertain, but computer modelling suggested concentrations between 0.1 and 50 percent.
By comparison, the percentage of water vapor in Earth’s atmosphere varies between 0.2 percent above the poles, and up to four percent in the tropics.
There was also evidence of hydrogen and helium as well. Nitrogen and methane may also be present but with current technology remain undetectable, the study said.
Further research will be able to determine the extent of cloud coverage and the percentage of water in the atmosphere.

Water is crucial in the search for life, in part because it carries oxygen.
“Life as we know is based on water,” said Tinetti.
K2-18b orbits a red dwarf star about 110 light years distant — a million billion kilometers — in the Leo constellation of the Milky Way, and is probably bombarded by more destructive radiation than Earth.
“It is likely that this is the first of many discoveries of potentially habitable planets,” said UCL astronomer Ingo Waldmann, also a co-author.
“This is not only because super-Earths like K2-18b are the most common planets in our galaxy, but also because red dwarfs — stars smaller than our Sun — are the most common stars.”
The new generation of space-based star gazing instruments led by the James Webb Space Telescope and the European Space Agency’s ARIEL mission will be able to describe exoplanet atmospheres in far greater detail.
ARIEL, slated for a 2028 launch, will canvas some 1,000 planets, a large enough sampling to look for patterns and identify outliers.
“Over 4,000 exoplanets have been detected but we don’t know much about their composition and nature,” said Tinetti. “By observing a large sample of planets, we hope to reveal secrets about their chemistry, formation and evolution.”
 


Huawei in public test as it unveils sanction-hit phone

Updated 19 September 2019

Huawei in public test as it unveils sanction-hit phone

  • Hit by US sanctions, Huawei's Mate 30 will not be allowed to use Google’s Play Store
  • Household-name services like WhatsApp, Instagram and Google Maps will be unavailable.
BERLIN: Chinese tech giant Huawei launches its latest high-end smartphone in Munich on Thursday, the first that could be void of popular Google apps because of US sanctions.
Observers are asking whether a phone without the Silicon Valley software that users have come to depend on can succeed, or whether Huawei will have found a way for buyers to install popular apps despite the constraints.
The company has maintained a veil of secrecy over its plans, set to be dropped at a 1200 GMT press conference revealing the Mate 30 and Mate 30 Pro models.
Huawei, targeted directly by the United States as part of a broader trade conflict with Beijing, was added to a “blacklist” in Washington in May.
Since then, it has been illegal for American firms to do business with the Chinese firm, suspected of espionage by President Donald Trump and his administration.
As a result, the new Mate will run on a freely available version of Android, the world’s most-used phone operating system that is owned by the search engine heavyweight.
While Mate 30 owners will experience little difference in the use of the system, the lack of Google’s Play Store — which provides access to hundreds of thousands of third-party apps and games as well as films, books and music — could hobble them.
Household-name services like WhatsApp, Instagram and Google Maps will be unavailable.
The tech press reports that this yawning gap in functionality has left some sellers reluctant to stock the new phones, fearing a wave of rapid-fire returns from dissatisfied customers.
Huawei president Richard Yu said at Berlin’s IFA electronics fair this month that his engineers found a “very simple” way to install the hottest apps without going via the Play Store.
Huawei could offer its own app store in a preliminary version, setting itself up as a competitor to the dominant Apple and Google offerings, observers speculate.
Over the longer term, the company could build out a similar “ecosystem” of devices, apps and services as the Silicon Valley companies that would bind users more closely to it.
The world’s second-largest smartphone maker after Samsung, Huawei earlier this month presented its proprietary operating system HarmonyOS, a potential replacement for Android.
The Mate 30 will not yet have HarmonyOS installed.
But it could make for a new round in the decades-old “OS wars” between Microsoft’s Windows and Apple’s Mac OS, then Android versus Apple’s iOS.
Meanwhile, Eric Xu, current holder of Huawei’s rotating chief executive chair, has urged Europe to foster an alternative to Google and Apple.
That could provide an opening for Huawei to build up Europe’s market of 500 million well-off consumers as a stronghold against American rivals.
“If Europe had its own ecosystem for smart devices, Huawei would use it... that would resolve the problem of European digital dependency” on the United States, Xu told German business daily Handelsblatt.
He added that his company would be prepared to invest in developing such joint European-Chinese projects.