When NASA's Dawn spacecraft arrived to orbit the dwarf planet Ceres in March 2015, mission scientists expected to find a heavily cratered body generally resembling the protoplanet Vesta, Dawn's previous port of call. Instead, as the spacecraft drew near to Ceres, a somewhat different picture began to emerge: Something has happened to Ceres to remove its biggest impact basins.

The Dawn team includes Arizona State University's David Williams, who is the director of the Ronald Greeley Center for Planetary Studies in ASU's School of Earth and Space Exploration. Wiliams oversees a team of researchers using Dawn data to map the geology of Ceres.

He says, "When we first starting looking at Ceres images, we noticed that there weren't any really large impact basins on the surface." None are larger than 177 miles (285 kilometers) across. This presents a mystery, he says, because Ceres must have been struck by large asteroids many times over its 4.5-billion-year history.

"Even Vesta, only about half of Ceres' size, has two big basins at its south pole. But at Ceres, all we saw was the Kerwan Basin, just 177 miles in diameter," Williams says. "That was a big red flag that something had happened to Ceres."

The Kerwan Basin's name was proposed by Williams, and it commemorates the Hopi Indian spirit of the sprouting corn.

Dawn lead investigator Marchi notes, "We concluded that a significant population of large craters on Ceres has been obliterated beyond recognition over geological time scales, which is likely the result of Ceres' peculiar composition and internal evolution."

The team's simulations of collisions with Ceres predicted that it should have 10 to 15 craters larger than 250 miles (400 kilometers) in diameter, and at least 40 craters larger than 60 miles (100 kilometers) wide. In reality, however, Dawn found that Ceres has only 16 craters larger than 60 miles, and none larger than the 177-mile Kerwan Basin.

Further study of Dawn's images revealed that Ceres does have three large-scale depressions called "planitiae" that are up to 500 miles (800 kilometers) wide. These have craters within them that formed in more recent times, but the depressions could be left over from bigger impacts.

One of the depressions, called Vendimia Planitia, is a sprawling area just north of the Kerwan Basin. Vendimia Planitia must have formed much earlier than Kerwan.

So what removed Ceres' large craters and basins? "If Ceres were highly rocky, we'd expect impact craters of all sizes to be preserved. Remote sensing from Earth, however, told us even before Dawn arrived that the crust of Ceres holds a significant fraction of ice in some form," Williams explains.

If Ceres' crust contained a large proportion of ice -- especially if mixed with salts -- that would weaken the crust and let the topography of a large basin relax and become smoother, perhaps even disappear.

In addition, says Williams, Ceres must have generated some internal heat from the decay of radioactive elements after it formed. This too could also have helped soften or erase large-scale topographic features.

He adds, "Plus we do see evidence of cryovolcanism -- icy volcanism -- in the bright spots found scattered over Ceres, especially in Occator Crater." Cryovolcanism behaves like the rocky kind, only at much lower temperatures, where "molten ice" -- water or brine -- substitutes for molten rock.

"It's possible that there are layers or pockets of briny water in the crust of Ceres," says Williams. "Under the right conditions, these could migrate to the surface and be sources for the bright spots."

For example, in Occator Crater, he points out, "the central bright spot is a domed feature which looks as if it has erupted or been pushed up from below."

NASA plans for Dawn to continue orbiting Ceres as the dwarf planet makes its closest approach to the Sun in April 2018. Scientists want to see if the increasing solar warmth triggers any activity or produces detectable changes in Ceres' surface.

"Ceres is revealing only slowly the answers to her many mysteries," Williams says. "Completing the geological maps over the next year, and further analysis of the compositional and gravity data, will help us understand better Ceres' geologic evolution."

The Daily Galaxy via University of Arizona

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This past March, Robin Li Yanhong, the founder and chief executive of China's Google, the online search giant Baidu, announced that he is looking to the nation's military to support the China Brain Project to make the mainland the world leader in developing artificial intelligence (AI) systems. It will be a massive, "state-level" initiative that could be comparable to how the Apollo space program to land the first humans on the moon in 1969.

Earlier in January of 2016 heoretical physicist Stephen Hawking warned this past January, 2016 that blindly embracing pioneering technology could trigger humanity's annihilation."The primitive forms of artificial intelligence we already have, have proved very useful. But I think the development of full artificial intelligence could spell the end of the human race," Hawking told the BBC in 2014. "Once humans develop artificial intelligence it would take off on its own, and re-design itself at an ever increasing rate. Humans, who are limited by slow biological evolution, couldn't compete and would be superseded."

Artificial intelligence will surpass human intelligence after 2020, predicts Vernor Vinge, a world-renowned pioneer in AI, who has warned about the risks and opportunities that an electronic super-intelligence would offer to mankind. "It seems plausible that with technology we can, in the fairly near future," says scifi legend Vernor Vinge, "create (or become) creatures who surpass humans in every intellectual and creative dimension. Events beyond such an event -- such a singularity -- are as unimaginable to us as opera is to a flatworm."

There was the psychotic HAL 9000 in "2001: A Space Odyssey," the humanoids which attacked their human masters in "I, Robot" and, of course, "The Terminator", where a robot is sent into the past to kill a woman whose son will end the tyranny of the machines.

Experts interviewed by AFP were divided. Some agreed with Hawking, saying that the threat, even if it were distant, should be taken seriously. Others said his warning seemed overblown. "I'm pleased that a scientist from the 'hard sciences' has spoken out. I've been saying the same thing for years," said Daniela Cerqui, an anthropologist at Switzerland's Lausanne University.

Gains in AI are creating machines that outstrip human performance, Cerqui argued. The trend eventually will delegate responsibility for human life to the machine, she predicted. "It may seem like science fiction, but it's only a matter of degrees when you see what is happening right now," said Cerqui. "We are heading down the road he talked about, one step at a time."

Nick Bostrom, director of a program on the impacts of future technology at the University of Oxford, said the threat of AI superiority was not immediate. Bostrom pointed to current and near-future applications of AI that were still clearly in human hands -- things such as military drones, driverless cars, robot factory workers and automated surveillance of the Internet. But, he said, "I think machine intelligence will eventually surpass biological intelligence -- and, yes, there will be significant existential risks associated with that transition."

Other experts said "true" AI -- loosely defined as a machine that can pass itself off as a human being or think creatively -- was at best decades away, and cautioned against alarmism.

Since the field was launched at a conference in 1956, "predictions that AI will be achieved in the next 15 to 25 years have littered the field," according to Oxford researcher Stuart Armstrong. "Unless we missed something really spectacular in the news recently, none of them have come to pass," Armstrong says in a book, "Smarter than Us: The Rise of Machine Intelligence."

Jean-Gabriel Ganascia, an AI expert and moral philosopher at the Pierre and Marie Curie University in Paris, said Hawking's warning was "over the top. Many things in AI unleash emotion and worry because it changes our way of life," he said. "Hawking said there would be autonomous technology which would develop separately from humans. He has no evidence to support that. There is no data to back this opinion."

"It's a little apocalyptic," said Mathieu Lafourcade, an AI language specialist at the University of Montpellier, southern France. "Machines already do things better than us," he said, pointing to chess-playing software. "That doesn't mean they are more intelligent than us."

Allan Tucker, a senior lecturer in computer science at Britain's Brunel University, took a look at the hurdles facing AI. Recent years have seen dramatic gains in data-processing speed, spurring flexible software to enable a machine to learn from its mistakes, he said. Balance and reflexes, too, have made big advances. Tucker pointed to the US firm Boston Dynamics as being in the research vanguard. "These things are incredible tools that are really adaptative to an environment, but there is still a human there, directing them," said Tucker. "To me, none of these are close to what true AI is."

Tony Cohn, a professor of automated reasoning at Leeds University in northern England, said full AI is "still a long way off... not in my lifetime certainly, and I would say still many decades, given (the) current rate of progress." Despite big strides in recognition programmes and language cognition, robots perform poorly in open, messy environments where there are lots of noise, movement, objects and faces, said Cohn.

Such situations require machines to have what humans possess naturally and in abundance -- "commonsense knowledge" to make sense of things. Tucker said that, ultimately, the biggest barrier facing the age of AI is that machines are... well, machines. "We've evolved over however many millennia to be what we are, and the motivation is survival. That motivation is hard-wired into us. It's key to AI, but it's very difficult to implement."

"The Singularity" is seen by some as the end point of our current culture, when the ever-accelerating evolution of technology finally overtakes us and changes everything. It's been represented as everything from the end of all life to the beginning of a utopian age, which you might recognize as the endgames of most other religious beliefs.

While the definitions of the Singularity are as varied as people's fantasies of the future, with a very obvious reason, most agree that artificial intelligence will be the turning point. Once an AI is even the tiniest bit smarter than us, it'll be able to learn faster and we'll simply never be able to keep up. This will render us utterly obsolete in evolutionary terms, or at least in evolutionary terms.

Susan Schneider of the University of Pennsylvania is one of the few thinkers—outside the realm of science fiction— that have considered the notion that artificial intelligence is already out there, and has been for eons.

Her recent study, Alien Minds, Schneider asks: "how might aliens think? And, would they be conscious? I do not believe that most advanced alien civilizations will be biological, Schneider says. The most sophisticated civilizations will be postbiological, forms of artificial intelligence or Alien superintelligence."

Search for Extraterrstrial Intelligence (SETI) programs have been searching for biological life. Our culture has long depicted aliens as humanoid creatures with small, pointy chins, massive eyes, and large heads, apparently to house brains that are larger than ours. Paradigmatically, they are “little green men.” While we are aware that our culture is anthropomorphizing, Schneider imagines that her suggestion that aliens are supercomputers may strike us as far-fetched. So what is her rationale for the view that most intelligent alien civilizations will have members that are superintelligent AI?

Schneider presents offer three observations that together, support her conclusion for the existence of alien superintelligence.

The first is "the short window observation": Once a society creates the technology that could put them in touch with the cosmos, they are only a few hundred years away from changing their own paradigm from biology to AI. This “short window” makes it more likely that the aliens we encounter would be postbiological.

The short window observation is supported by human cultural evolution, at least thus far. Our first radio signals date back only about a hundred and twenty years, and space exploration is only about fifty years old, but we are already immersed in digital technology, such as cell-phones and laptop computers.

Devices such as the Google Glass promise to bring the Internet into more direct contact with our bodies, and it is probably a matter of less than fifty years before sophisticated internet connections are wired directly into our brains.

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The Daily Galaxy via AFP and South China Morning Post

Image credit: With thanks to Paul Imre

Light from a distant galaxy can be strongly bent by the gravitational influence of a foreground galaxy, an effect called strong gravitational lensing. Normally a single galaxy is lensed at a time. The same foreground galaxy can - in theory - simultaneously lens multiple background galaxies. Although extremely rare, such a lens system offers a unique opportunity to probe the fundamental physics of galaxies and add to our understanding of cosmology. One such lens system has recently been discovered and the discovery was made not in an astronomer's office, but in a classroom. It has been dubbed the Eye of Horus, and this ancient eye in the sky will help us understand the history of the universe.

Subaru Telescope organizes a school for undergraduate students each year. One such session was held in September 2015 at the NAOJ headquarters in Mitaka, Tokyo (Fig. 2). Subaru is currently undertaking a massive survey to image a large area of the sky at an unprecedented depth with Hyper Suprime-Cam as part of the Subaru Strategic Program. A group of astronomers and young students were analyzing some of that Hyper Suprime-Cam data at the school when they found a unique lens system. It was a classic case of a serendipitous discovery.

"When I was looking at HSC images with the students, we came across a ring-like galaxy and we immediately recognized it as a strong-lensing signature," said Masayuki Tanaka, the lead author of a science paper on the system's discovery. "The discovery would not have been possible without the large survey data to find such a rare object, as well as the deep, high quality images to detect light from distant objects."

Arsha Dezuka, a student who was working on the data, was astonished at the find. "It was my first time to look at the astronomical images taken with Hyper Suprime-Cam and I had no idea what the ring-like galaxy is," she said. "It was a great surprise for me to learn that it is such a rare, unique system!"

A close inspection of the images revealed two distinct arcs/rings of light with different colors. This strongly suggested that two distinct background galaxies were being lensed by the foreground galaxy. The lensing galaxy has a spectroscopic redshift of z = 0.79 (which means it's 7.0 billion light-years away, Note 1) based on data from the Sloan Digital Sky Survey. Follow-up spectroscopic observations of the lensed objects using the infrared-sensitive FIRE spectrometer on the Magellan Telescope confirmed that there are actually two galaxies behind the lens. One lies at z = 1.30 and the other is at z = 1.99 (9.0 and 10.5 billion light-years away, respectively).

"The spectroscopic data reveal some very interesting things about the background sources," said Kenneth Wong from NAOJ, the second author of the scientific paper describing the system. "Not only do they confirm that there are two sources at different distances from us, but the more distant source seems to consist of two distinct clumps, which could indicate an interacting pair of galaxies. Also, one of the multiple images of that source is itself being split into two images, which could be due to a satellite galaxy that is too faint for us to see."

The distinct features for the system (several bright knots, an arc, a complete Einstein ring) arise from the nice alignment of the central lens galaxy and both sources, creating an eye-like structure (Fig.3). The astronomers dubbed it Eye of Horus, for the sacred eye of an ancient Egyptian god, since the system has an uncanny resemblance to it.

The survey with Hyper Suprime-Cam is only 30% complete and it will collect data for several more years. Astronomers expect to find roughly 10 more such systems in the survey, which will provide important insights into the fundamental physics of galaxies as well as how the universe expanded over the last several billion years.

The "Canarias Einstein ring" shown at the top of the page is one of the most symmetrical discovered until now and is almost circular, showing that the two galaxies are almost perfectly aligned, with a separation on the sky of only 0.2 arcseconds. The source galaxy is 10,000 million light years away from us. Due to the expansion of the Universe, this distance was smaller when its light started on its journey to us, and has taken 8,500 million years to reach us. We observe it as it was then: a blue galaxy which is beginning to evolve, populated by young stars which are forming at a high rate. The lens galaxy is nearer to us, 6,000 million light years away, and is more evolved. Its stars have almost stopped forming, and its population is old.

The Daily Galaxy via National Institutes of Natural Sciences

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