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Astronomers Have Found Potential Life-Supporting Conditions on The Nearest Exoplanet

In August of 2016, astronomers from the European Southern Observatory (ESO) announced the discovery of an exoplanet in the neighboring system of Proxima Centauri. The news was greeted with considerable excitement, as this was the closest rocky planet to our Solar System that also orbited within its star’s habitable zone.

Since then, multiple studies have been conducted to determine if this planet could actually support life.

Unfortunately, most of the research so far has indicated that the likelihood of habitability are not good. Between Proxima Centauri’s variability and the planet being tidally-locked with its star, life would have a hard time surviving there.

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Astronomers take first, high-resolution look at huge star-forming region of Milky Way

Astronomers from the United States and South Korea have made the first high-resolution, radio telescope observations of the molecular clouds within a massive star-forming region of the outer Milky Way.

“This region is behind a nearby cloud of dust and gas,” said Charles Kerton, an associate professor of physics and astronomy at Iowa State University and a member of the study team. “The cloud blocks the light and so we have to use infrared or radio observations to study it.”

The Milky Way region is called CTB 102. It’s about 14,000 light years from Earth. It’s classified as an HII region, meaning it contains clouds of ionized—charged—hydrogen atoms. And, because of its distance from Earth and the dust and gas in between, it has been difficult to study.

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The discrete-time physics hiding inside our continuous-time world

Scientists believe that time is continuous, not discrete—roughly speaking, they believe that it does not progress in “chunks,” but rather “flows,” smoothly and continuously. So they often model the dynamics of physical systems as continuous-time “Markov processes,” named after mathematician Andrey Markov. Indeed, scientists have used these processes to investigate a range of real-world processes from folding proteins, to evolving ecosystems, to shifting financial markets, with astonishing success.

However, invariably a scientist can only observe the state of a system at discrete times, separated by some gap, rather than continually. For example, a stock market analyst might repeatedly observe how the state of the market at the beginning of one day is related to the state of the market at the beginning of the next day, building up a conditional probability distribution of what the state of the second day is given the state at the first day.

In a pair of papers, one appearing in this week’s Nature Communications and one appearing recently in the New Journal of Physics, physicists at the Santa Fe Institute and MIT have shown that in order for such two– dynamics over a set of “visible states” to arise from a continuous-time Markov process, that Markov process must actually unfold over a larger space, one that includes hidden states in addition to the visible ones. They further prove that the evolution between such a pair of times must proceed in a finite number of “hidden timesteps”, subdividing the interval between those two times. (Strictly speaking, this proof holds whenever that evolution from the earlier time to the later time is noise-free—see paper for technical details.)

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The world’s largest plane just flew for the first time

After years of development in the desert north of Los Angeles, a gigantic, six-engined mega jet with the wingspan of an American football field flew Saturday morning for the first time.

“We finally did it,” said Stratolaunch Systems CEO Jean Floyd at a news conference from the hangar at Mojave Air & Space Port. “It was an emotional moment to watch this bird take flight.”

Stratolaunch, the company founded in 2011 by the late Microsoft co-founder Paul Allen, conducted the first test flight of the world’s largest plane.

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