This week in science: Could aliens spot Earth?

This week in science is a review of the most interesting scientific news of the past week.

Could aliens spot Earth?

Scientists have been looking at the stars for centuries, studying their dynamics throughout the universe around us. It has been a remarkable journey of scientific and technological achievements that has taken humanity to the Moon and its designs even further - such as the Voyager 1, which launched 40 years ago and is now almost 13 billion miles (almost 21 billion kilometers or 139.7 AU, the distance from our planet to the Sun) away from Earth and still counting.

Also, by using telescopes and missions such as SuperWASP and Kepler, scientists have already identified thousands of exoplanets - planets orbiting stars other than our Sun; most of them were discovered ‘on transit’, while they were crossing in front of their host stars and therefore casting a shadow over the light detected here on Earth. But if we can spot those planets from here, why cannot we be spotted from other exoplanets as well?

That question motivated a group of scientists from the Queen's University in Belfast and from the Max Planck Institute for Solar System Research in Germany to conduct a reverse study to find out how an alien observer could detect Earth using our own methods. To do so, the scientists have identified parts of the sky from where the planets in our solar system could be seen in their transit zones, as detailed in the diagram above.

Their conclusions were that planets closer to the Sun, such as Mercury, Venus, Earth, and Mars, are more likely to be spotted than those farther, even though they are far smaller than planets like Jupiter and Saturn. Furthermore, the scientists could determine from where in the sky the transits of the solar system planets are possible to be spotted, as can be seen in the image at the top. According to Katja Poppenhaeger, a co-author of the study:

We estimate that a randomly positioned observer would have roughly a 1 in 40 chance [sic] of observing at least one planet. The probability of detecting at least two planets would be about ten times lower, and to detect three would be a further ten times smaller than this.

Finally, the scientists have identified 68 planets where observers would see one or more of the planets in our solar system in transit. From those, nine can observe Earth's transit directly, although none of them is believed to be habitable.

Source: Phys.org | Images: 2MASS, A. Mellinger and R. Wells

A new quantum computing architecture for silicon quantum processors

A team of engineers from the University of New South Wales in Australia has developed a new chip design for quantum computing based on what they have called 'flip-flop qubits'. The new design can be used to manufacture silicon quantum processors that do not require the precise placement of atoms as in other architectures, which consists in a major issue for large scale production.

The new architecture is based on ‘spin qubits’ and uses both the electron and the nucleus of the atoms. But instead of using magnetic signals to control the qubits, the new architecture does so by using electric ones, which are significantly easier to distribute and localize within an electronic chip.

Another important achievement of the new architecture is that it allows qubits to be placed hundreds of nanometers apart and remain coupled. If the qubits are placed too close or too far apart from each other, the entanglement between them does not occur.

The team has struck an A$83 million (more than $66 million) deal to develop, by 2022, a 10-qubit prototype silicon quantum integrated circuit. The financial contribution involves the telecom giant Telstra, Australia's Commonwealth Bank and the Australian and New South Wales governments.

Source: Phys.org | Image: Tony Melov and UNSW

To round off our weekly science wrap up, it was found by a team of researchers at China’s Zhejiang University that Alexa, Google Assistant, Siri, and others are vulnerable to 'silent' commands. Dubbed ‘DolphinAttack’, the researchers have managed to modulate the frequency of a voice command made by a human into ultrasonic frequencies, therefore inaudible to human ears but detectable by the microphones present on consumer devices.

Also, a new study conducted by scientists from Stanford University has concluded that artificial intelligence can largely determine a person's sexuality from photos. According to their results, AI can now determine the sexuality of a person four out of five times. Unfortunately, as pointed out by the scientists, such technology "exposes a threat to the privacy and safety of gay men and women”.