Science & TechnologyS


Meteor

NASA to participate in tabletop exercise simulating asteroid impact


Jet Propulsion Laboratory - NASA
Wed, 21 Apr 2021 06:41 UTC
Asteroid crater from space station
© NASA, International Space Station Expedition 59This image was captured by the International Space Station Expedition 59 crew as they orbited 400 kilometers above Quebec, Canada. Right of center, the ring-shaped lake is a modern reservoir within the eroded remnant of an ancient 100 kilometer diameter impact crater, which is over 200 million years old.
JPL's Center for Near Earth Object Studies will lead the hypothetical impact scenario to see how international agencies respond to an actual impact prediction.

During the week of April 26, members of NASA's Planetary Defense Coordination Office (PDCO) will participate in a "tabletop exercise" to simulate an asteroid impact scenario. The exercise depicting this fictional event is being led by NASA's Jet Propulsion Laboratory's Center for Near Earth Object Studies (CNEOS), allowing NASA's PDCO and other U.S. agencies and space science institutions, along with international space agencies and partners, to use the fictitious scenario to investigate how near-Earth object (NEO) observers, space agency officials, emergency managers, decision makers, and citizens might respond and work together to an actual impact prediction and simulate the evolving information that becomes available in the event an asteroid impact threat is discovered.

The fictitious impact scenario will occur during the 7th IAA Planetary Defense Conference, hosted by the United Nations Office for Outer Space Affairs in cooperation with ESA (European Space Agency), and will evolve over the five days of the conference, starting Monday, April 26. At several points in the conference program, leaders of the exercise will brief participants on the latest status of the fictitious scenario and solicit feedback for next steps based on the simulated data that is "discovered" each day. These type of exercises are specifically identified as part of the National Near-Earth Object Preparedness Strategy and Action Plan developed over a three-year period and published by the White House in June 2018.

Comment: Meanwhile a record number of asteroids were observed flying past Earth in 2020 - Despite lockdowns interrupting surveys.

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Arrow Up

Largest flare from sun's nearest neighbor breaks records

Daniel Strain
University of Colorado Boulder
Wed, 21 Apr 2021 19:00 UTC
Proxima Centauri
© NRAO/S. DagnelloArtist's conception of a violent flare erupting from the star Proxima Centauri.
Scientists have spotted the largest flare ever recorded from the sun's nearest neighbor, the star Proxima Centauri.

The research, which appears today in The Astrophysical Journal Letters, was led by CU Boulder and could help to shape the hunt for life beyond Earth's solar system.

CU Boulder astrophysicist Meredith MacGregor explained that Proxima Centauri is a small but mighty star. It sits just four light-years or more than 20 trillion miles from our own sun and hosts at least two planets, one of which may look something like Earth. It's also a "red dwarf," the name for a class of stars that are unusually petite and dim.

Proxima Centauri has roughly one-eighth the mass of our own sun. But don't let that fool you.

In their new study, MacGregor and her colleagues observed Proxima Centauri for 40 hours using nine telescopes on the ground and in space. In the process, they got a surprise: Proxima Centauri ejected a flare, or a burst of radiation that begins near the surface of a star, that ranks as one of the most violent seen anywhere in the galaxy.

"The star went from normal to 14,000 times brighter when seen in ultraviolet wavelengths over the span of a few seconds," said MacGregor, an assistant professor at the Center for Astrophysics and Space Astronomy (CASA) and Department of Astrophysical and Planetary Sciences (APS) at CU Boulder.

The team's findings hint at new physics that could change the way scientists think about stellar flares. They also don't bode well for any squishy organism brave enough to live near the volatile star.

"If there was life on the planet nearest to Proxima Centauri, it would have to look very different than anything on Earth," MacGregor said. "A human being on this planet would have a bad time."
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Nuke

Study says nuclear fallout showing up in U.S. honey decades after bomb tests

Nikk Ogasa
Science Magazine
Tue, 20 Apr 2021 18:36 UTC
Nuclear Fallout in Honey
© ARX0NT/ISTOCKFlowering plants can transfer radiocesium from soils to honey bees, who can then concentrate the contaminant in honey.

Fallout from nuclear bomb tests in the 1950s and '60s is showing up in U.S. honey, according to a new study. Although the levels of radioactivity aren't dangerous, they may have been much higher in the 1970s and '80s, researchers say.

"It's really quite incredible," says Daniel Richter, a soil scientist at Duke University not involved with the work. The study, he says, shows that the fallout "is still out there and disguising itself as a major nutrient."

In the wake of World War II, the United States, the former Soviet Union, and other countries detonated hundreds of nuclear warheads in aboveground tests. The bombs ejected radiocesium — a radioactive form of the element cesium — into the upper atmosphere, and winds dispersed it around the world before it fell out of the skies in microscopic particles. The spread wasn't uniform, however. For example, far more fallout dusted the U.S. east coast, thanks to regional wind and rainfall patterns.

Radiocesium is soluble in water, and plants can mistake it for potassium, a vital nutrient that shares similar chemical properties. To see whether plants continue to take up this nuclear contaminant, James Kaste, a geologist at the College of William & Mary in Williamsburg, Virginia, gave his undergraduate students an assignment: Bring back local foods from their spring break destinations to test for radiocesium.

One student returned with honey from Raleigh, North Carolina. To Kaste's surprise, it contained cesium levels 100 times higher than the rest of the collected foods. He wondered whether eastern U.S. bees gathering nectar from plants and turning it into honey were concentrating radiocesium from the bomb tests.
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Chalkboard

Mystery solved: Scientists crack 'the Brazil-nut' puzzle, how do the largest nuts rise to the top?


PhysOrg
Mon, 19 Apr 2021 17:05 UTC
Brazil nuts bowl
© Pixabay/CC0 Public Domain
Scientists have for the first time captured the complex dynamics of particle movement in granular materials, helping to explain why mixed nuts often see the larger Brazil nuts gather at the top. The findings could have vital impact on industries struggling with the phenomenon, such as pharmaceuticals and mining.

Many people will have the experience of dipping their hands into a bag of mixed nuts only to find the Brazil nuts at the top. This effect can also be readily observed with cereal boxes, with the larger items rising to the top. Colloquially, this phenomenon of particles segregating by their size is known as the 'Brazil-nut effect' and also has huge implications for industries where uneven mixing can critically degrade product quality.

Now, for the first time, scientists at The University of Manchester have used time-resolved 3D imaging to show how the Brazil nuts rise upwards through a pile of nuts. The work shows the importance of particle shape in the de-mixing process.
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Info

Fearsome tyrannosaurs may have hunted in packs study suggest


University of Arkansas
Tue, 20 Apr 2021 19:07 UTC
TRex Skull
© Courtesy of the Bureau of Land Management"Hollywood" specimen, same species as Teratophoneus, discovered approximately two miles north of the "Rainbows and Unicorns Quarry" on Grand Staircase-Escalante National Monument.
The fearsome tyrannosaur dinosaurs that ruled the northern hemisphere during the Late Cretaceous period (66-100 million years ago) may not have been solitary predators as popularly envisioned, but social carnivores similar to wolves, according to a new study.

The finding, based on research at a unique fossil bone site inside Utah's Grand Staircase-Escalante National Monument containing the remains of several dinosaurs of the same species, was made by a team of scientists including Celina Suarez, U of A associate professor of geosciences.

"This supports our hypothesis that these tyrannosaurs died in this site and were all fossilized together; they all died together, and this information is key to our interpretation that the animals were likely gregarious in their behavior," Suarez said.

The research team also included scientists from the U.S. Bureau of Land Management, Denver Museum of Nature and Science, Colby College of Maine and James Cook University in Australia. The study examines a unique fossil bone site inside Grand Staircase-Escalante National Monument called the "Rainbows and Unicorns Quarry" that they say exceeded the expectations raised even from the site's lofty nickname.

"Localities [like Rainbows and Unicorns Quarry] that produce insights into the possible behavior of extinct animals are especially rare and difficult to interpret," said tyrannosaur expert Philip Currie in a press release from the Bureau of Land Management. "Traditional excavation techniques, supplemented by the analysis of rare earth elements, stable isotopes and charcoal concentrations convincingly show a synchronous death event at the Rainbows site of four or five tyrannosaurids. Undoubtedly, this group died together, which adds to a growing body of evidence that tyrannosaurids were capable of interacting as gregarious packs."
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Fireball 5

How to survive a killer asteroid

Cody Cassidy
Wired
Fri, 09 Apr 2021 07:00 UTC
asteroid image
© Elena Lacey/Wired
The impact that wiped out the dinosaurs would probably have killed you too — unless you were in the exact right place and had made the exact right plans.

LET'S SAY FOR a moment you want to camp alongside the dinosaurs. But not just any dinosaurs. You want to camp alongside the most famous. The most fearsome. So let's say you spin the dials on a time machine to 66.5 million years ago and you travel back to the late Cretaceous period.

There's the tyrannosaurus hunting the triceratops. There's the alamosaurus, one of the largest creatures to ever walk the earth. There's the tank-like ankylosaurus crushing opponents with its wrecking-ball tail. And just as you settle down on one particular evening, there's a brand-new star in the northern hemisphere sky.

The star won't flash, flare up, or blaze across the horizon. It will appear as stationary and as twinkly as all the others. But look again a few hours later and you might think this new star seems a little brighter. Look again the next night and it will be the brightest star in the sky. Then it will outshine the planets. Then the moon. Then the sun. Then it will streak through the atmosphere, strike the earth, and unleash 100 million times more energy than the largest thermonuclear device ever detonated. You'll want to pack up your tent before then. And maybe move to the other side of the planet.
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Info

Laser to zap space debris, funding for SKA observatory in Australia

Tory Shepherd
Cosmos Magazine
Fri, 16 Apr 2021 18:05 UTC
Space Junk
© NASA illustration, courtesy Orbital Debris Program Office.This graphic of orbital debris, or “space junk" (any human-made object in orbit around the Earth that no longer serves a useful purpose) comes from 2009. The same year, a US communications satellite owned by a private company, Iridium, collided with a non-functioning Russian satellite. The collision destroyed both satellites and created a field of debris that endangered other orbiting satellites.
Australian National University researchers working with defence technology company EOS have developed lasers to blast space debris out of orbit.

Space debris (or "junk") is becoming a serious problem as orbits get more congested with decommissioned space craft and other objects, and new satellites. Debris can smash into assets such as the International Space Station, and even a small object can cause great damage in space.

The ANU's "guide star laser" will use adaptive optics to better spot, track, and move space debris.

Adaptive optics correct for haziness caused by atmospheric turbulence - the effect that makes stars twinkle. It "untwinkles" them.

Lead researcher, ANU professor Celine D'Orgeville, said "removing the twinkle from the stars" cuts through the atmospheric distortion so objects can be seen more clearly.

"This includes small, human-made objects - like weather and communications satellites, or space junk," she said.

EOS group chief executive officer Ben Greene said EOS maintains a database of space objects and will now be able to actively manipulate them.

"Space debris is a major society threat, globally but especially in Australia due to our heavy economic dependence on space assets," he said.
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Bullseye

Unlikely Twitter war: Steak-umm vs. Neil deGrasse Tyson

Elizabeth Whately
Evolution News
Sat, 17 Apr 2021 16:17 UTC
Neil deGrasse Tyson
Neil deGrasse Tyson
Neil deGrasse Tyson may be the world's most popular science communicator. But on Twitter, he's the gift that keeps on giving, offering a blend of pedantic and self-important content that comes in for regular trolling. Recently, he encountered resistance from an unlikely quarter: the official Twitter account of Steak-umm, which is "an American brand of thin-sliced frozen steaks."

It all started on April 11 when Tyson tweeted out, "The good thing about Science is that it's true, whether or not you believe in it." A typical Tyson tweet, complete with the capitalization of "Science." But whoever runs Steak-umm's Twitter was unimpressed, re-tweeting with the suggestion "log off bro," then backing up the suggestion with remarkably spot-on follow-up comments. In one follow-up, they point out that Tyson's tweet was ironic, since "by framing science itself as 'true' he's influencing people to be more skeptical of it in a time of unprecedented misinformation," an implied reference to the ongoing chaos of COVID cross-messaging. Then they offer a better definition of science: "an ever refining process to find truth, not a dogma."

Comment: Neil deGrasse Tyson has managed to craft a slightly more credible scientist persona than say, Bill Nye. Yet, look at the use he is making of it: Plus, his faith in "peer review" should have been badly shaken long before now:

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Microscope 1

Human cells grown in monkey embryos reignite ethics debate

Nicola Davis
The Guardian
Thu, 15 Apr 2021 16:30 UTC
monkey embryo
© Weizhi Ji/Kunming University of Science and Technology/PAA photo issued by the Salk Institute shows human cells grown in an early stage monkey embryo.
Monkey embryos containing human cells have been produced in a laboratory, a study has confirmed, spurring fresh debate into the ethics of such experiments.

The embryos are known as chimeras, organisms whose cells come from two or more "individuals", and in this case, different species: a long-tailed macaque and a human.

In recent years researchers have produced pig embryos and sheep embryos that contain human cells - research they say is important as it could one day allow them to grow human organs inside other animals, increasing the number of organs available for transplant.

Now scientists have confirmed they have produced macaque embryos that contain human cells, revealing the cells could survive and even multiply.

In addition, the researchers, led by Prof Juan Carlos Izpisua Belmonte from the Salk Institute in the US, said the results offer new insight into communications pathways between cells of different species: work that could help them with their efforts to make chimeras with species that are less closely related to our own.

Comment: See also:

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Galaxy

Solar cycle 25 arriving ahead of schedule


Space Weather
Fri, 16 Apr 2021 17:19 UTC
sunspot
Above: Observed and predicted sunspot numbers: more

You probably think Solar Cycle 25 is a dud. Think again. Despite long stretches of spotless quiet, the new solar cycle is actually running ahead of schedule. In this plot, the red curve shows NOAA's predicted sunspot counts for Solar Cycle 25; the orange curve shows the new best fit:

"The sun is performing as we expected--maybe even a little better," says Lisa Upton of Space Systems Research Corporation. She's a co-chair of the NOAA/NASA Solar Cycle 25 Prediction Panel. "In 2019, the panel predicted that Solar Cycle 25 would peak in July 2025 (± 8 months) with a maximum sunspot count of 115 ± 10. The current behavior of the sun is consistent with an early onset near the beginning of our predicted range."

Comment: It would appear that we're entering a period unlike modern science has ever known: Professor Valentina Zharkova: "We entered the 'modern' Grand Solar Minimum on June 8, 2020"

See also: And check out SOTT radio's:

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