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Astronomers Agree on Universe's Birthday – 13.77 Billion Years Old – SciTechDaily

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From an observatory high above Chile’s Atacama Desert, astronomers have taken a new look at the oldest light in the universe.

Their observations, plus a bit of cosmic geometry, suggest that the universe is 13.77 billion years old – give or take 40 million years. A Cornell researcher co-authored one of two papers about the findings, which add a fresh twist to an ongoing debate in the astrophysics community.

The new estimate, using data gathered at the National Science Foundation’s Atacama Cosmology Telescope (ACT), matches the one provided by the standard model of the universe, as well as measurements of the same light made by the European Space Agency’s Planck satellite, which measured remnants of the Big Bang from 2009 to ’13.

The research was published on December 30, 2020, in the Journal of Cosmology and Astroparticle Physics.

The lead author of “The Atacama Cosmology Telescope: A Measurement of the Cosmic Microwave Background Power Spectra at 98 and 150 GHz” is Steve Choi, NSF Astronomy and Astrophysics Postdoctoral Fellow at the Cornell Center for Astrophysics and Planetary Science, in the College of Arts and Sciences.

In 2019, a research team measuring the movements of galaxies calculated that the universe is hundreds of millions of years younger than the Planck team predicted. That discrepancy suggested a new model for the universe might be needed and sparked concerns that one of the sets of measurements might be incorrect.

“Now we’ve come up with an answer where Planck and ACT agree,” said Simone Aiola, a researcher at the Flatiron Institute’s Center for Computational Astrophysics and first author of one of two papers. “It speaks to the fact that these difficult measurements are reliable.”

Reference: “The Atacama Cosmology Telescope: a measurement of the Cosmic Microwave Background power spectra at 98 and 150 GHz” by Steve K. Choi, Matthew Hasselfield, Shuay-Pwu Patty Ho, Brian Koopman, Marius Lungu, Maximilian H. Abitbol, Graeme E. Addison, Peter A. R. Ade, Simone Aiola, David Alonso, Mandana Amiri, Stefania Amodeo, Elio Angile, Jason E. Austermann, Taylor Baildon, Nick Battaglia, James A. Beall, Rachel Bean, Daniel T. Becker, J Richard Bond, Sarah Marie Bruno, Erminia Calabrese, Victoria Calafut, Luis E. Campusano, Felipe Carrero, Grace E. Chesmore, Hsiao-mei Cho, Susan E. Clark, Nicholas F. Cothard, Devin Crichton, Kevin T. Crowley, Omar Darwish, Rahul Datta, Edward V. Denison, Mark J. Devlin, Cody J. Duell, Shannon M. Duff, Adriaan J. Duivenvoorden, Jo Dunkley, Rolando Dünner, Thomas Essinger-Hileman, Max Fankhanel, Simone Ferraro, Anna E. Fox, Brittany Fuzia, Patricio A. Gallardo, Vera Gluscevic, Joseph E. Golec, Emily Grace, Megan Gralla, Yilun Guan, Kirsten Hall, Mark Halpern, Dongwon Han, Peter Hargrave, Shawn Henderson, Brandon Hensley, J. Colin Hill, Gene C. Hilton, Matt Hilton, Adam D. Hincks, Renée Hložek, Johannes Hubmayr, Kevin M. Huffenberger, John P. Hughes, Leopoldo Infante, Kent Irwin, Rebecca Jackson, Jeff Klein, Kenda Knowles, Arthur Kosowsky, Vincent Lakey, Dale Li, Yaqiong Li, Zack Li, Martine Lokken, Thibaut Louis, Amanda MacInnis, Mathew Madhavacheril, Felipe Maldonado, Maya Mallaby-Kay, Danica Marsden, Loïc Maurin, Jeff McMahon, Felipe Menanteau, Kavilan Moodley, Tim Morton, Sigurd Naess, Toshiya Namikawa, Federico Nati, Laura Newburgh, John P. Nibarger, Andrina Nicola, Michael D. Niemack, Michael R. Nolta, John Orlowski-Sherer, Lyman A. Page, Christine G. Pappas, Bruce Partridge, Phumlani Phakathi, Heather Prince, Roberto Puddu, Frank J. Qu, Jesus Rivera, Naomi Robertson, Felipe Rojas, Maria Salatino, Emmanuel Schaan, Alessandro Schillaci, Benjamin L. Schmitt, Neelima Sehgal, Blake D. Sherwin, Carlos Sierra, Jon Sievers, Cristobal Sifon, Precious Sikhosana, Sara Simon, David N. Spergel, Suzanne T. Staggs, Jason Stevens, Emilie Storer, Dhaneshwar D. Sunder, Eric R. Switzer, Ben Thorne, Robert Thornton, Hy Trac, Jesse Treu, Carole Tucker, Leila R. Vale, Alexander Van Engelen, Jeff Van Lanen, Eve M. Vavagiakis, Kasey Wagoner, Yuhan Wang, Jonathan T. Ward, Edward J. Wollack, Zhilei Xu, Fernando Zago and Ningfeng Zhu, 30 December 2020, Journal of Cosmology and Astroparticle Physics.
DOI: 10.1088/1475-7516/2020/12/045

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NASA Pulls Plug On InSight Lander’s Mars Mole – Forbes

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NASA has pulled the plug on its InSight lander’s Mars mole, more than two years after the lander touched down at Elysium Planitia. The German-built Mars mole heat probe could simply never penetrate the hard exterior surface of its landing site in order to make the kind of measurements necessary to give planetary scientists the first real clues as to the makeup of the Martian interior.

For nearly two years, the InSight, short for Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport’s mole probe has been attempting to burrow into the Martian surface to take the planet’s internal temperature, says NASA. But the soil’s unexpected tendency to clump deprived the spike-like mole of the friction it needs to hammer itself to a sufficient depth, the team notes.

Part of the spacecraft’s Heat Flow and Physical Properties Package (HP3), the mole was intended to be a self-hammering probe that would burrow down to almost 16 feet (five meters) below Mars’ surface. This would have enabled planetary scientists to better understand whether Mars’ interior is radically different from Earth or our own Moon.

“We’ve given it everything we’ve got, but Mars and our heroic mole remain incompatible,” HP3’s principal investigator, Tilman Spohn of DLR said in a statement. “Fortunately, we’ve learned a lot that will benefit future missions that attempt to dig into the subsurface.”

The mole itself is a 16-inch-long spike designed to drag with it a ribbonlike tether that extends from the spacecraft, says NASA.  The idea was that Temperature sensors are embedded along the tether to measure the planet’s interior heat.

But InSight landed in an area with an unusually thick duricrust, or a layer of cemented soil, NASA reports.  Rather than being loose and sandlike, as expected, the dirt granules stick together, says the agency.

Unfortunately, to work properly, the mole needs friction from the soil in order to travel downward. Without it, says NASA, recoil from its self-hammering action causes it to simply bounce in place.  Paradoxically, it’s loose soil, not this cement-like duricrust that InSight has encountered at its landing site, that would ideally provide the needed friction as it falls around the mole.

The landing site at Elysium Planitia, a broad, equatorial volcanic plain, was selected in part because it has so few visible rocks, implying few large subsurface rocks.  Designed to measure heat flowing from the planet once the mole has dug at least 10 feet deep, the mole is strong enough to nudge small rocks out of its way, says NASA.   

But after repeated attempts to aid the mole in its actions over a two year period using the spacecraft’s robotic arm in ways that it was never intended, the team realized that they were in a no-win situation.

Meanwhile, the rest of InSight’s instruments are functioning and taking data. In fact, NASA says that the mission intends to employ the robotic arm in burying the tether that conveys data and power between the lander and InSight’s seismometer, which has recorded more than 480 marsquakes. Burying it will help reduce temperature changes that have created cracking and popping sounds in seismic data, the team notes.

The InSight mission itself has been recently extended to late next year. Along with hunting for marsquakes, the lander hosts a radio experiment that is collecting data to reveal whether the planet’s core is liquid or solid, says NASA. And InSight’s weather sensors are capable of providing some of the most detailed meteorological data ever collected on Mars, says the agency. Together with weather instruments aboard NASA’s Curiosity rover and the Perseverance rover, which lands on Feb. 18th, the team says that the three spacecraft will create the first meteorological network on another planet.

Could the problem simply be an ordinary rock?

“We don’t know for sure, because we can’t see underground,” Spohn said in a statement.  “[But] there’s also the possibility that we’ve hit a rock.”

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Earth's magnetic field controls space weather, shields us from solar wind: new study – UCalgary News

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Researchers in the Faculty of Science have made an important contribution to new findings about Earth’s magnetic field and its role in shielding our planet from solar wind, the continuous stream of charged particles emanated by the sun.

In the discovery, published in Nature Communications, a team of Alberta-based scientists found that electromagnetic energy originating in the solar wind shows a clear preference to head toward Earth’s northern polar regions rather than their southern counterparts.

The new findings suggest that, in addition to acting as a shield from incoming solar particles, the magnetic field also actively controls how the energy is distributed and channeled into Earth’s atmosphere.

International research collaboration helps yield new discovery

Using information from the European Space Agency’s (ESA)’s Swarm satellite constellation, researchers in the University of Alberta’s Department of Physics analyzed data from electric field instruments (EFIs) designed and operated at the University of Calgary by a team led by Dr. David Knudsen, PhD, and Dr. Johnathan Burchill, PhD, both in the Department of Physics and Astronomy. Lead author Dr. Ivan Pakhotin at the University of Alberta and co-authors at both universities discovered the “surprising” imbalance in how Earth’s magnetic field responds to space weather driven by the sun.

The high-calibre international partnership between the two universities and the ESA reflects the research excellence in space science in Alberta. The University of Calgary has been Canada’s most prolific university-based provider of space instrumentation, with more than 20 instruments developed and launched into space over the university’s 50-plus-year history, according to Knudsen.

While the terms “North Pole” and “South Pole” conjure images of polar bears and penguins, they refer to the north and south poles of our planet’s magnetic field, and loosely line up with Earth’s rotational axis. Earth’s magnetic field is visible in action when the aurora borealis or northern lights appear in the northern night skies, the result of its interaction with charged atomic particles from the sun.

While the dancing ribbons of light are a beautiful sight, they’re representative of a constant bombardment of charged particles in the solar wind, and can have significant impacts on some of our most important systems like communication networks and navigation systems (like GPS and satellites). In severe cases, solar storms can cause communication and electrical systems and even satellites to fail.

“Because the south magnetic pole is further away from Earth’s spin axis than the north magnetic pole, an asymmetry is imposed on how much energy makes its way down toward Earth in the north and south,” explains Pakhotin, the paper’s lead author and postdoctoral fellow in UAlberta’s Department of Physics.

While researchers aren’t yet sure what the effects of this asymmetry might be, the findings suggest that it could also point to an asymmetry between the aurora australis in the south and the aurora borealis in the north. Further, they suggest that the dynamics of upper atmospheric chemistry may vary between the hemispheres, particularly when geomagnetic activity is strong.

UCalgary contribution to Swarm satellite constellation essential to new findings

Knudsen and Burchill specialize in near-Earth space research, and have extensive experience in the development of space instrumentation. Knudsen serves as lead scientist for the EFIs on the Swarm satellites; Burchill has responsible for their operation since launch in 2013.

Each EFI contains two sensors known as thermal ion imagers. Initially developed at UCalgary with support from ESA and the Canadian Space Agency, and built by Ontario-based COM DEV Canada (now Honeywell), the thermal ion imagers use the same technology used in digital cameras — CCD detector technology — to detect charged particles. The sensors then produce precision measurements of ionospheric winds and temperatures. “This information is used to calculate the electric field, an important counterpart to the magnetic field,” Knudsen explains.

Understanding Earth’s electric and magnetic field environment helps scientists design better electrical grids and early warning systems when solar disturbances like mass coronal ejections or solar storms occur and affect Earth. However, the primary motivation of this research is to understand the fundamental behaviour of the charged-particle gases (plasmas) surrounding Earth, and the causes and consequences of the northern and southern lights, key aspects of which remain unexplained. 

Swarm’s three satellites return information about how the magnetic field protects Earth from the dangerous particles in solar wind, along with how the field is generated and how the position of Earth’s magnetic north changes over time.

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NASA's Orion spacecraft is ready to fly to the Moon – Yahoo Movies Canada

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The Canadian Press

Extremists exploit a loophole in social moderation: Podcasts

Major social platforms have been cracking down on the spread of misinformation and conspiracy theories in the leadup to the presidential election, and expanded their efforts in the wake of the Jan. 6 Capitol riot. But Apple and Google, among others, have left open a major loophole for this material: Podcasts. Podcasts made available by the two Big Tech companies let you tune into the world of the QAnon conspiracy theory, wallow in President Donald Trump’s false claims of a stolen election and bask in other extremism. Accounts that have been banned on social media for election misinformation, threatening or bullying, and breaking other rules also still live on as podcasts available on the tech giants’ platforms. Conspiracy theorists have peddled stolen-election fantasies, coronavirus conspiracies and violent rhetoric. One podcaster, RedPill78, called the Capitol siege a “staged event” in a Jan. 11 episode of Red Pill News. The day before the Capitol riot, a more popular podcast, X22 Report, spoke confidently about a Trump second term, explained that Trump would need to “remove” many members of Congress to further his plans, and said “We the people, we are the storm, and we’re coming to DC.” Both are available on Apple and Google podcast platforms. Podcasting “plays a particularly outsized role” in propagating white supremacy, said a 2018 report from the Anti-Defamation League. Many white supremacists, like QAnon adherents, support Trump. Podcasting’s an intimate, humanizing mode of communication that lets extremists expound on their ideas for hours at a time, said Oren Segal of ADL’s Center on Extremism. Elsewhere on social media, Twitter,Facebook and YouTube have been cracking down on accounts amplifying unfounded QAnon claims that Trump is fighting deep state enemies and cannibals operating a child-sex trafficking ring. A major talk radio company, Cumulus, told its hosts to tone down rhetoric about stolen elections and violent uprisings or risk termination, although it’s not clear what impact that dictate has had. Google-owned YouTube axed “Bannon’s War Room,” a channel run by Trump loyalist Steve Bannon on Jan. 8 after he spread false election claims and called for the beheading of Dr. Anthony Fauci, the top U.S. infectious-disease expert. But podcast versions of Bannon’s show live on at Apple and Google. Spotify took it down in November, according to one of its hosts. “Podcasts filled with hatred and incitement to violence should not be treated any differently than any other content,” Segal said. “If you’re going to take a strong stance against hate and extremism in the platform in any way, it should be all-inclusive.” Apple, Spotify and Google curate lists of top podcasts and recommend them to users. Apple and Spotify are the dominant players in the U.S., with other players far behind, said Dave Zohrob, CEO of the podcast analytics firm Chartable. Despite its name recognition, Google remains a tiny presence. Spotify said it takes down podcasts that violate its policies against hate speech, copyright violations or break any laws, using “algorithmic and human detection measures” to identify violations. Apple’s guidelines prohibit content that is illegal or promotes violence, graphic sex or drugs or is “otherwise considered obscene, objectionable, or in poor taste.” Apple did not reply to repeated questions about its content guidelines or moderation. Google declined to explain the discrepancy between what’s available on YouTube and what’s on Google Podcasts, saying only that its podcast service “indexes audio available on the web” much the way its search engine indexes web pages. The company said it removes podcasts from its platform “in very rare circumstances, largely guided by local law.” X22 Report and Bannon’s War Room were No. 20 and No. 32 on Apple’s list of top podcasts on Friday. (Experts say that list measures a podcast’s momentum rather than total listeners.) X22 Report said in October that it was suspended by YouTube and Spotify and last week by Twitter. It’s no longer available on Facebook, either. It is supported by ads for products such as survivalist food, unlicensed food supplements and gold coins, which run before and during the podcasts. The website for Red Pill News said YouTube banned its videos in October and that a Twitter suspension followed. The podcast is available on Apple and Google, but not Spotify. Several QAnon proponents affected by the crackdown sued YouTube in October, calling its actions a “massive de-platforming.” Among the plaintiffs are X22 Report, RedPill78 and David Hayes, who runs another conspiracy podcast called Praying Medic that’s available on Apple and Google, but not Spotify. Melody Torres, who podcasts at SoulWarrior Uncensored, self-identifies as a longtime QAnon follower and said in a recent episode that her podcast is “just my way of not being censored.” She said she was kicked off Twitter in January and booted from Instagram four times last year. She currently has Instagram, Facebook and YouTube accounts; her podcast is available on Apple and Google. Spotify removed the podcast Friday after The Associated Press inquired about it. X22 Report, RedPill78 and Hayes did not respond to requests for comment sent via their websites. Torres did not reply to a Facebook message. Podcasts suffer from the same misinformation problem as other platforms, said Shane Creevey, head of editorial for Kinzen, a startup created by former Facebook and Twitter executives that offers a disinformation tracker to companies, including some that host or curate podcasts. Creevey points out that it’s harder to analyze misinformation from video and audio than from text. Podcasts can also run for hours, making them difficult to monitor. And podcasting has additional challenges in that there are no reliable statistics on their audience, unlike a YouTube stream, which shows views, or a tweet or Facebook post, which shows likes and shares, Creevey said. But some argue that tech-company moderation is opaque and inconsistent, creating a new set of problems. Censorship “goes with the tide against what’s popular in any given moment,” said Jillian York, an expert at the Electronic Frontier Foundation, a digital-rights group. Right now, she said, “that tide is against the speech of right-wing extremists … but tomorrow the tide might be against opposition activists.” ___ AP Technology Editor David Hamilton contributed to this article. Tali Arbel, The Associated Press

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