Los Angeles, June 27 (Xinhua/UNB) -- The National Aeronautics and Space Administration (NASA) has selected two partner organizations to run a nationwide contest giving US students a chance to make history by naming the Mars 2020 rover, according to a release of NASA's Jet Propulsion Laboratory (JPL) on Tuesday.
Battelle Education, of Columbus, Ohio, and Future Engineers, of Burbank, California, will collaborate with NASA on the Mars 2020 "Name the Rover" contest, which will be open to students from kindergarten to 12th grade in the fall of 2019.
The student contest is part of NASA's efforts to engage the public in its missions to the Moon and Mars.
"We're very excited about this exceptional partnership," said Mars 2020 program executive George Tahu in NASA's Planetary Science Division.
"Contests like this present excellent opportunities to invite young students and educators to be a part of this journey to understand the possibilities for life beyond Earth and to advance new capabilities in exploration technology."
The currently unnamed rover is a robotic scientist weighing more than 1,000 kg, according to the JPL. It will search for signs of past microbial life, characterize the planet's climate and geology, collect samples for future return to Earth and pave the way for human exploration of the Red Planet.
The spacecraft is targeted for a July 2020 launch and is expected to touch down on Mars in February 2021.
Beijing, June 27 (Xinhua/UNB) -- Chinese researchers have improved a diagnostics system for nuclear fusion devices, paving the way for producing controlled thermonuclear fusion power in the future.
At the temperatures required for fusion reactions, the matter can only exist in the plasma state, free negative electrons and positive nuclei. Some fusion reactors use a magnetic field to confine hot plasma for fusion actions to take place.
Plasma is hard to control and contain and is subject to sudden termination, usually with very little warning. When a disruption occurs, the considerable thermal and magnetic energy contained within the plasma is suddenly released very quickly, which can lead to damages.
Scattering of laser light from the electrons in plasma is known as Thomson scattering. It has been used as an established method to measure the electron temperature and density in fusion devices, assisting in the identification of critical points of the fusion plasmas.
Researchers from Aerospace Information Research Institute, Chinese Academy of Sciences and University of Science and Technology of China (USTC) tested their new Thomson scattering diagnostic system in the Keda Torus eXperiment, a fusion device at the USTC.
The new system used laser beams of 200 Hz repetition rate and 1.5 J pulse energy each as the source of intense radiation for scattering and achieved the accurate detection of the electron temperature under 5 electron volts, the energy unit that electron temperature is often expressed in terms of.
The time response of the diagnostic system using a single laser unit is two times faster than that of a conventional one.
According to the researchers, the frequency of laser beam decides how often the diagnostic system measure the electron temperature. In a hot magnetically confined plasma, the laser system thus can record fast changes and measure turbulence and electron fluctuations so as to ensure safe operation of the fusion reactor.
In future studies, the researchers plan to develop Thomson scattering diagnostic system based on laser beams with much higher frequency.
Nuclear fusion has the potential to revolutionize energy production, with virtually endless power available from common elements like hydrogen and helium and no dangerous waste products produced.
Jerusalem, June 27 (Xinhua/UNB) -- Israeli researchers have deciphered the way that biological cells ingest food, which may lead to an explanation of many activities in the cell, the northern Israel Institute of Technology reported on Wednesday.
Biological cells, like the whole organism, cannot live without eating. Since they do not have an eating organ, the cells evolved into a clever ingestion technique called endocytosis.
In this process, the cell membrane has a dent that develops and protrudes inward, and then the membrane forms an internal bubble in which the food particle is trapped.
To complete the engulfing process, it is necessary to cut the bubble's neck and release the nutrients into dedicated organelles in the cell.
Thus, the molecules of the protein dynamin tighten around the bladder's neck and cut it, releasing the food particle inside the cell.
In the study, published in the journal Proceedings of the National Academy of Sciences (PNAS), the researchers examined the activity of the dynamin, whose structure is a helix, like other proteins and the DNA molecule, whose structure is a double helix.
The researchers showed that the shape and stability of the dynamin chain are largely determined by the angle of insertion of the dynamins' edges in the membrane of the cell, and this is critical to the success of cutting the membrane neck and breaking down the chain of dynamin to release the nutrients inside the cell.
Furthermore, the researchers successfully predicted the arrangement of the protein structure in the cells.
Following the findings, the team presented a new geometric object -- the tilted helix
San Francisco, June 27 (AP/UNB) — Facebook CEO Mark Zuckerberg says the company is evaluating how it should handle "deepfake" videos created with artificial intelligence and high-tech tools to yield false but realistic clips.
In an interview at the Aspen Ideas Festival in Colorado on Wednesday, Zuckerberg said it might make sense to treat such videos differently from other misinformation such as false news. Facebook has long held that it should not decide what is and isn't true, leaving such calls instead to outside fact-checkers.
But Zuckerberg says it's worth asking whether deepfakes are a "completely different category" from regular false statements. He says developing a policy on these videos is "really important" as AI technology grows more sophisticated.
Facebook, like other social media companies, does not have a specific policy against deepfakes, whose potential threat has emerged only in the last couple of years. Company executives have said in the past that it makes sense to look at them under the broader umbrella of false or misleading information. But Zuckerberg is signaling that this view might be changing, leaving open the possibility that Facebook might ban deepfakes altogether.
Doing so, of course, could get complicated. Satire, art and political dissent could be swept up in any overly broad ban, creating more headaches from Facebook.
Other false videos could still get a pass. For instance, the recent altered video of House Speaker Nancy Pelosi that made her sound like she was slurring her words does not meet the definition of a deepfake.
Dhaka, June 27 ( UNB) - Underneath the salty waters of the North Atlantic ocean, geologists have discovered a giant aquifer of freshwater, hidden from view just off the US coast, reports Science Alert.
While the vast size of this massive cache is surprising, it's not entirely unexpected. Signals of the water first showed up in the 1970s, but until now, nobody suspected that this huge reservoir trapped in porous rock might run almost the entire length of the US Northeast.
"We knew there was freshwater down there in isolated places, but we did not know the extent or geometry," says marine geologist Chloe Gustafson from Columbia University.
In 2015, some of Gustafson's fellow researchers conducted a pilot study off the coast of New Jersey and the Massachusetts island of Martha's Vineyard.
Using an electromagnetic receiver deployed from the research vessel Marcus G. Langseth, the team was looking to survey offshore groundwater deposits buried in sediments below continental shelves.
Exploratory prospecting by oil companies as far back as the 1970s had occasionally discovered freshwater when drilling for the fossil fuel, so scientists knew something was down there; but data on the resource – and the size of the cache – was in short supply.
To rectify that, the research crew on the Marcus G. Langseth surveyed the two Northeast coast locations for 10 days, looking for signs of electrical conductivity in the waters below the vessel.
Salt water is a more effective conductor of electromagnetic (EM) waves than fresh water, so EM receivers deployed off the coast enabled the researchers to map the extent of the mysterious aquifer.
The results, published in a study detailing the first comprehensive attempt to map this giant reservoir, reveal a mostly "continuous submarine aquifer system spans at least 350 km [217 miles] of the US Atlantic coast and contains about 2,800 cubic kilometres of low-salinity groundwater".
Due to the nature of the EM mapping technique, the results remain somewhat interpretive for now, but the team infers that the aquifer's freshwater cache likely runs all the way from Delaware (at the south end) up past New Jersey, New York, Connecticut, Rhode Island, and all the way to Massachusetts.
As crazy as it sounds, the groundwater reservoir might even extend farther than that, the researchers hint.
"If we consider the potential northeast and southwest extensions beyond our profiles, there may be several times more groundwater underlying the northeast portion of the US Atlantic continental shelf, representing a freshwater resource that rivals the largest onshore aquifers," the authors explain.
As for how the aquifer got there, the researchers say it likely happened when vast amounts of fresh meltwater from the last Ice Age got trapped in rocky sediment.
To use the water for drinking purposes – if we were to one day decide to tap it, that is – it would first need to be desalinated, since parts of it would be brackish (slightly salty), especially the portions closest to the seawater periphery.
For now, nobody's suggesting we need to do that, but the existence of the giant aquifer suggests similar groundwater systems could easily be hidden in other hotter and drier parts of the world, like California, Australia, or the Middle East.
"It could turn out to be an important resource in other parts of the world," Gustafson says.