While headlines routinely report on "close shaves" and "near-misses" when near-Earth objects (NEOs) such as asteroids or comets pass relatively close to Earth, the real work of preparing for the possibility of a NEO impact with Earth goes on mostly out of the public eye.

For more than 20 years, NASA and its international partners have been scanning the skies for NEOs, which are asteroids and comets that orbit the Sun and come within 30 million miles (50 million kilometers) of Earth's orbit. International groups, such as NASA's Planetary Defense Coordination Office (PDCO), the European Space Agency's Space Situational Awareness-NEO Segment, and the International Asteroid Warning Network (IAWN) have made better communication of the hazards posed by NEOs a top priority.

In the spirit of better communication, next week at the 2019 Planetary Defense Conference, NASA's PDCO and other U.S. agencies and space science institutions, along with international partners, will participate in a "tabletop exercise" that will play out a realistic-but fictional-scenario for an asteroid on an impact trajectory with Earth.

A tabletop exercise of a simulated emergency is commonly used in disaster management planning to help inform involved players of important aspects of a possible disaster and identify issues for accomplishing a successful response. In next week's exercise, attendees at the conference will play out a fictional NEO impact scenario developed by the NASA Jet Propulsion Laboratory's Center for NEO Studies (CNEOS).

Until recently, quasars were thought to have essentially fixed positions in the sky. While near-Earth objects move along complex trajectories, quasars are so remote that they were believed to offer stable and reliable reference points for use in navigation and plate tectonics research. Now, an international team of astrophysicists featuring researchers from the Moscow Institute of Physics and Technology has found that quasars are not entirely motionless and explained this behavior. The findings were published in the Monthly Notices of the Royal Astronomical Society.

"The apparent positions of quasars change with the radiation frequency used to observe them. Researchers predicted this effect about 40 years ago based on the theory of synchrotron radiation and observed it soon afterwards," explains Alexander Pushkarev, a leading researcher at the Crimean Astrophysical Observatory and Lebedev Physical Institute of the Russian Academy of Sciences. "Our study aimed to find whether this effect varies with time, and if so, then on what timescales and to what extent the apparent position shift changes."

The tube-dwelling anemone is an ancient sea creature that resembles a prehistoric flower. The animals live slow, long and predictable lifestyles and look fairly similar from species to species.

It'd be easy to use the word "simple" when considering this relative of coral and jellyfish. But wait -- not so fast.

New research on tube anemones is challenging everything that evolutionary biologists thought they knew about sea animal genetics. The mitochondrial DNA of the tube anemone, or Ceriantharia, is a real head scratcher, from its unexpected arrangement to its previously unimagined magnitude.

Researchers, including a team from The Ohio State University, have published new findings showing that the DNA of the tube anemone does what few other species' mitochondrial genomes have been shown to do. It defies the classic doughnut shape it "should" be in and is arranged in several fragmented pieces, the number of which vary depending on the species.

You've gotta hand it to America's space scientists: they're resilient. Despite an admission that they may not be able to stop the asteroid Bennu from turning Earth into a smoldering crater filled with the ashen remains of its human inhabitants, NASA's Planetary Defense Coordination Office (PDCO) has teamed up with FEMA and other agencies for what amounts to a wargaming exercise to prepare themselves for a catastrophic asteroid strike.

The best part of this? The ESA is tweeting out bits and pieces of the scenario - that an asteroid named 2019PDC has been spotted and calculated to have a 1 in 100 chance of striking Earth - as if it were happening in real time. The agency has wisely hashtagged the relevant tweets with #FICTIONALEVENT to avoid any War of the Worlds scenarios.

Walmart this morning unveiled a new "store of the future" and test grounds for emerging technologies, including AI-enabled cameras and interactive displays. The store, a working concept called the Intelligent Retail Lab - or "IRL" for short - operates out of a Walmart Neighborhood Market in Levittown, N.Y.

The store is open to customers and is one of Walmart's busiest Neighborhood Market stores, containing more than 30,000 items, the retailer says, which allows it to test out technology in a real-world environment.

Similar to Amazon Go's convenience stores, the store has a suite of cameras mounted in the ceiling. But unlike Amazon Go, which is a grab-and-go store with smaller square footage, Walmart's IRL spans 50,000 square feet of retail space and is staffed by more than 100 employees.

Plus, in Walmart's case, these AI-powered cameras are not being used to determine which items customers are buying in order to automatically charge them. It still has traditional checkout stations. Instead, the cameras will monitor inventory levels to determine, for example, if staff needs to bring out more meat from the back-room refrigerators to restock the shelves, or if some fresh items have been sitting too long on the shelf and need to be pulled.

The idea is that the AI will help the store associates know more precisely where and when to restock products. And this, in turn, means customers will know the produce and meat is always fresh and in stock when they arrive.

A review of The Gendered Brain: The new neuroscience that shatters the myth of the female brain, by Gina Rippon. The Bodley Head Ltd (March 2019).

Imagine your response to picking up a copy of the leading scientific journal Nature and reading the headline: "The myth that evolution applies to humans." Anyone even vaguely familiar with the advances in neuroscience over the past 15-20 years regarding sex influences on brain function might have a similar response to a recent headline in Nature: "Neurosexism: the myth that men and women have different brains" subtitled "the hunt for male and female distinctions inside the skull is a lesson in bad research practice."

Turns out that yet another book, this one with a fawning review in Nature, claims to "shatter" myths about sex differences in the brain while in fact perpetuating the largest one. Editors at Nature decided to give this book their imprimatur. Ironically, within a couple of days of the Nature review being published came a news alert from the American Association for the Advancement of Science titled, "Researchers discover clues to brain differences between males and females," and a new editorial in Lancet Neurology titled "A spotlight on sex differences in neurological disorders," both of which contradict the book's core thesis. So what in the name of good science is going on here?

Holograms are a staple in science fiction, but creating ones detailed enough to have serious applications in the real world has proved difficult. While scientists have been slowly pushing the field of holographic projection forward, they haven't been able to overcome a problem called cross-talk. However, in a recent paper published in Nature, they have been able to manipulate the shape of light to overcome this, thus allowing them to produce 3D holograms that are orders of magnitude clearer, larger, and more detailed.

What Are Holograms?
Simple holograms are 2D surfaces that produce the illusion of a 3D object when light is shined through it.

These are created by splitting a laser into two beams, bouncing one off an object, bouncing the other off a mirror, and recombining them on a specialized photographic plate.

Lasers are coherent light, meaning they're composed of one specific frequency, in that all light waves are moving in unison. When two coherent light waves are combined, a process known as interference, an orderly and predictable pattern is produced. The peaks amplify other peaks, the troughs amplify other troughs, and peaks and troughs cancel each other out, thus producing alternating bands of light and dark.

However, when the light is reflected off of an object, it's no longer coherent, and when it's recombined with the coherent light of the laser beam, an interference pattern is created that is specific to the object.

The photographic plate is placed exactly where the light is recombined, thus capturing the unique interference pattern, which holds all the information needed to reproduce a 3D image of the object, including the depth cues of perspective and parallax (the difference in the apparent position of an object viewed along two different lines of sight). To reproduce the image of the object, the reference beam needs to be shined through the back of the plate, thus hitting the interference pattern and producing the object beam, as if it has just come off the object.

Put another way, (the reference beam) + (the object beam) = (the interference pattern on the plate), and shining the reference beam in from the other direction is like rearranging this equation so that (the interference pattern on the plate) - (the reference beam) = (the object beam), making the image appear.

The Sevmash Shipyard in Severodvinsk in the northern Arkhangelsk Region is set to float out the special-purpose nuclear-powered submarine Belgorod on April 23. TASS has put together material on this ship.

The Belgorod is a nuclear-powered special-purpose and research submarine. Its exact operational characteristics have been classified. Russia's Defense Ministry did not officially comment on media reports on this submarine.

Project's history and specifics

The shipbuilders are building the submarine based on an incompletely constructed Project 949A 'Antey' nuclear-powered underwater cruiser. The submarine was laid out at the Sevmash Shipyard on July 24, 1992 but its construction was suspended in 1997. In the 2000s, attempts were made to restart work on completing the sub's construction under the improved Project 949AM but a lack of financing frustrated this effort. In the early 2010s, a decision was made to rebuild the Belgorod under the new Project 09852 developed by the Rubin Central Design Bureau for Marine Engineering (St. Petersburg). The renewed keel-laying ceremony for the sub under construction No. 91664 was held on December 20, 2012 with the participation of Admiral Viktor Chirkov (the Russian Navy commander-in-chief in 2012-2016).

Scientists have discovered how a family of proteins that regulates the activity of transposable elements in the genome allows them to make inheritable changes to the growing fetus.

The human genome is fascinating. Once predicted to contain about a hundred thousand protein-coding genes, it now seems that the number is closer to twenty thousand, and maybe less. And although our genome is made up of about three billion units -- "base pairs" -- many of them don't seem to belong to specific genes, and for that reason they were delegated to the dustbin of genetics: they were literally called "junk DNA."

But as it turned out, junk DNA is actually critical in coordinating and regulating the work of actual genes. For example, there are sequences of DNA that "jump" around the genome and influence gene expression. These jumping units are called "transposable elements" and their number is estimated at over 4.5 million in a single genome.

As a genetic material, DNA is responsible for all known life. But DNA is also a polymer. Tapping into the unique nature of the molecule, Cornell engineers have created simple machines constructed of biomaterials with properties of living things.

Using what they call DASH (DNA-based Assembly and Synthesis of Hierarchical) materials, Cornell engineers constructed a DNA material with capabilities of metabolism, in addition to self-assembly and organization - three key traits of life.

"We are introducing a brand-new, lifelike material concept powered by its very own artificial metabolism. We are not making something that's alive, but we are creating materials that are much more lifelike than have ever been seen before," said Dan Luo, professor of biological and environmental engineering in the College of Agriculture and Life Sciences.

The paper, "Dynamic DNA Material With Emergent Locomotion Behavior Powered by Artificial Metabolism," published April 10 in Science Robotics.