Researchers show how intelligent aliens might draw nearly-limitless power from a black hole using a Dyson sphere.

 

The search for extraterrestrial intelligence (SETI) has been conducted for nearly 60 yr. A Dyson sphere, a spherical structure that surrounds a star and transports its radiative energy outwards as an energy source for an advanced civilization, is one of the main targets of SETI to identify intelligent aliens around galactic energy sources.

 

Read the full article at: www.livescience.com

Scientists just collected the first measurements of violent eruptions from a dense, magnetic star that spat out as much energy as a billion suns — and it happened in a fraction of a second.

 

This type of star, known as a magnetar, is a neutron star with an exceptionally strong magnetic field, and magnetars often flare spectacularly and without warning. But even though magnetars can be thousands of times brighter than our sun, their eruptions are so brief and unpredictable that they’re challenging for astrophysicists to find and study.

 

A neutron star forms when a massive star collapses at the end of its life. As the star dies in a supernova, protons and electrons in its core are crushed into a compressed solar mass that combines intense gravity with high-speed rotation and powerful magnetic forces, according to NASA. The result, a neutron star, is approximately 1.3 to 2.5 solar masses — one solar mass is the mass of our sun, or about 330,000 Earths — crammed into a sphere measuring just 12 miles (20 kilometers) in diameter. 

 

Matter in neutron stars is so densely packed that an amount the size of a sugar cube would weigh more than 1 billion tons (900 million metric tons), and a neutron star’s gravitational pull is so intense that a passing marshmallow would hit the star’s surface with the force of 1,000 hydrogen bombs, according to NASA.

 

Magnetars have magnetic fields that are 1,000 times stronger than those of other neutron stars, and they are more powerful than any other magnetic object in the universe. Our sun pales in comparison to these bright, dense stars even when they aren’t erupting, study lead author Alberto J. Castro-Tirado, a research professor with the Institute for Astrophysics of Andalucía at the Spanish Research Council, said in the statement. “Even in an inactive state, magnetars can be 100,000 times more luminous than our sun,” Castro-Tirado said. “But in the case of the flash that we have studied — GRB2001415 — the energy that was released is equivalent to that which our sun radiates in 100,000 years.”

A giant energy flare

The magnetar that produced the brief eruption is located in the Sculptor Galaxy, a spiral galaxy about 13 million light-years from Earth, and is “a true cosmic monster,” study co-author Victor Reglero, director of UV’s Image Processing Laboratory, said in the statement. The giant flare was detected on April 15, 2020 by the Atmosphere–Space Interactions Monitor (ASIM) instrument on the International Space Station, researchers reported Dec. 22 in the journal Nature.

 

Artificial intelligence (AI) in the ASIM pipeline detected the flare, enabling the researchers to analyze that brief, violent energy surge; the flare lasted just 0.16 seconds and then the signal decayed so rapidly that it was nearly indistinguishable from background noise in the data. The study authors spent more than a year analyzing ASIM’s two seconds of data collection, dividing the event into four phases based on the magnetar’s energy output, and then measuring variations in the star’s magnetic field caused by the energy pulse when it was at its peak. 

 

 

It’s almost as if the magnetar decided to broadcast its existence “from its cosmic solitude” by shouting into the void of space with the force “of a billion suns,” Reglero said.

Read the full article at: www.space.com

ESA’s exoplanet mission Cheops has revealed that an exoplanet orbiting its host star within a day has a deformed shape more like that of a rugby ball than a sphere. This is the first time that the deformation of an exoplanet has been detected, offering new insights into the internal structure of these star-hugging planets.

 

The planet, known as WASP-103b is located in the constellation of Hercules. It has been deformed by the strong tidal forces between the planet and its host star WASP-103, which is about 200 degrees hotter and 1.7 times larger than the sun.

 

We experience tides in the oceans of Earth mainly due to the Moon tugging slightly on our planet as it orbits us. The sun also has a small but significant effect on tides, however it is too far from Earth to cause major deformations of our planet. The same cannot be said for WASP-103b, a planet almost twice the size of Jupiter with 1.5 times its mass, orbiting its host star in less than a day. Astronomers have suspected that such a close proximity would cause monumental tides, but up until now they haven’t been able to measure them.

 

Using new data from ESA’s Cheops space telescope, combined with data that had already been obtained by the NASA/ESA Hubble Space Telescope and NASA’s Spitzer Space Telescope, astronomers have now been able to detect how tidal forces deform exoplanet WASP-103b from a usual sphere into a rugby ball shape.

 

Cheops measures exoplanet transits—the dip in light caused when a planet passes in front of its star from our point of view. Ordinarily, studying the shape of the light curve will reveal details about the planet such as its size. The high precision of Cheops together with its pointing flexibility, which enables the satellite to return to a target and to observe multiple transits, has allowed astronomers to detect the minute signal of the tidal deformation of WASP-103b. This distinct signature can be used to unveil even more about the planet.

 

“It’s incredible that Cheops was actually able to reveal this tiny deformation,” says Jacques Laskar of Paris Observatory, Université Paris Sciences et Lettres, and co-author of the research. “This is the first time such analysis has been made, and we can hope that observing over a longer time interval will strengthen this observation and lead to better knowledge of the planet’s internal structure.”

Read the full article at: phys.org

Researchers at the Italian Institute of Technology (IIT) have recently been exploring a fascinating idea, that of creating humanoid robots that can fly. To efficiently control the movements of flying robots, objects or vehicles, however, researchers require systems that can reliably estimate the intensity of the thrust produced by propellers, which allow them to move through the air.

 

As thrust forces are difficult to measure directly, they are usually estimated based on data collected by onboard sensors. The team at IIT recently introduced a new framework that can estimate thrust intensities of flying multi-body systems that are not equipped with thrust-measuring sensors. This framework, presented in a paper published in IEEE Robotics and Automation Letters, could ultimately help them to realize their envisioned flying humanoid robot.

 

“Our early ideas of making a flying humanoid robot came up around 2016,” Daniele Pucci, head of the Artificial and Mechanical Intelligence lab that carried out the study, told TechXplore. “The main purpose was to conceive robots that could operate in disaster-like scenarios, where there are survivors to rescue inside partially destroyed buildings, and these buildings are difficult to reach because of potential floods and fire around them.”

 

The key objective of the recent work by Pucci and his colleagues was to devise a robot that can manipulate objects, walk on the ground and fly. As many humanoid robots can both manipulate objects and move on the ground, the team decided to extend the capabilities of a humanoid robot to include flight; rather than developing an entirely new robotic structure.

 

“Once provided with flight abilities, humanoid robots could fly from one building to another avoiding debris, fire and floods,” Pucci said. “After landing, they could manipulate objects to open doors and close gas valves, or walk inside buildings for indoor inspection, for instance looking for survivors of a fire or natural disaster.”

Initially, Pucci and his colleagues tried to provide iCub, a renowned humanoid robot created at IIT, with the ability to balance its body on the ground, for instance standing on a single foot. Once they achieved this, they started working on broadening the robot’s locomotion skills, so that it could also fly and move in the air. The team refer to the area of research they have been focusing on as ‘aerial humanoid robotics.”

 

“To the best of our knowledge, we produced the first work about flying humanoid robots,” Pucci said. “That paper was obviously testing flight controllers in simulation environments only, but given the promising outcomes, we embarked upon the journey of designing iRonCub, the first jet-powered humanoid robot presented in our latest paper.”

Read the full article at: techxplore.com

Webb often gets called the replacement for Hubble, but we prefer to call it a successor. After all, Webb is the scientific successor to Hubble; its science goals were motivated by results from Hubble. Hubble’s science pushed us to look to longer wavelengths to “go beyond” what Hubble has already done. In particular, more distant objects are more highly redshifted, and their light is pushed from the UV and optical into the near-infrared. Thus observations of these distant objects (like the first galaxies formed in the Universe, for example) requires an infrared telescope.

 

This is the other reason that Webb is not a replacement for Hubble; its capabilities are not identical. Webb will primarily look at the Universe in the infrared, while Hubble studies it primarily at optical and ultraviolet wavelengths (though it has some infrared capability). Webb also has a much bigger mirror than Hubble. This larger light collecting area means that Webb can peer farther back into time than Hubble is capable of doing. Hubble is in a very close orbit around the earth, while Webb will be 1.5 million kilometers (km) away at the second Lagrange (L2) point.

 

Webb will observe primarily in the infrared and will have four science instruments to capture images and spectra of astronomical objects. These instruments will provide wavelength coverage from 0.6 to 28 micrometers (or “microns”; 1 micron is 1.0 x 10-6 meters). The infrared part of the electromagnetic spectrum goes from about 0.75 microns to a few hundred microns. This means that Webb’s instruments will work primarily in the infrared range of the electromagnetic spectrum, with some capability in the visible range (in particular in the red and up to the yellow part of the visible spectrum).

 

The instruments on Hubble can observe a small portion of the infrared spectrum from 0.8 to 2.5 microns, but its primary capabilities are in the ultra-violet and visible parts of the spectrum from 0.1 to 0.8 microns.

 

Why are infrared observations important to astronomy? Stars and planets that are just forming lie hidden behind cocoons of dust that absorb visible light. (The same is true for the very center of our galaxy.) However, infrared light emitted by these regions can penetrate this dusty shroud and reveal what is inside.

 

At left are infrared and visible light images from the Hubble Space Telescope of the Monkey Head Nebula, a star-forming region. A jet of material from a newly forming star is visible in one of the pillars, just above and left of centre in the right-hand image. Several galaxies are seen in the infrared view, much more distant than the columns of dust and gas.

Read the full article at: www.jwst.nasa.gov

Machine learning algorithms provide a way to detect misinformation based on writing style and how articles are shared. On topics as varied as climate change and the safety of vaccines, you will find a wave of misinformation all over social media. Trust in conventional news sources may seem lower than ever, but researchers are working on ways to give people more insight on whether they can believe what they read. Researchers have been testing artificial intelligence (AI) tools that could help filter legitimate news. But how trustworthy is AI when it comes to stopping the spread of misinformation?

 

Researchers at the Rensselaer Polytechnic Institute (RPI) and the University of Tennessee collaborated to study the role of AI in helping people identify whether the news they’re reading is legitimate or not. The research paper, “Tailoring Heuristics and Timing AI Interventions for Supporting News Veracity Assessments,” was published in Computers in Human Behavior Reports.  It discussed how crowdsourcing marketplace Amazon Mechanical Turk (AMT) can be used to identify misinformation for fresh news and specific heuristics, which are rules of thumb used to process information and consider its veracity. In other words, heuristics are essentially “shortcuts for decisions,” explained Dorit Nevo, an associate professor at RPI’s Lally School of Management and a lead author for the paper.

 

The study found that AI would be successful in flagging false stories only if the reader did not already have an opinion on the topic, Nevo said. When study subjects were set in their beliefs, confirmation bias kept them from reassessing their views.

Read the full article at: spectrum.ieee.org