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White dwarf measured before it exploded as a Supernova

Brian Koberlein
Universe Today
Sat, 12 Jun 2021 20:05 UTC
Type Ia Supernova
© NASA, ESA, and A. Field (STScI)The progenitor of a Type Ia Supernova.
Type Ia supernovae are an important tool for modern astronomy. They are thought to occur when a white dwarf star captures mass beyond the Chandrasekhar limit, triggering a cataclysmic explosion. Because that limit is the same for all white dwarfs, Type Ia supernovae all have about the same maximum brightness. Thus, they can be used as standard candles to determine galactic distances. Observations of Type Ia supernova led to the discovery of dark energy and that cosmic expansion is accelerating.

While these supernovae have revolutionized our understanding of the universe, they aren't quite as standard as we first proposed. Some, such as SN 1991T are much brighter, while others, such as SN 1991bg are much dimmer. There is also a variation known as Type Iax, where the white dwarf isn't completely destroyed by the explosion. We can generally take these variations into account when calculating stellar distances, but it would be good to have a better understanding of the mechanism behind their maximum brightness.

According to theoretical models, the maximum brightness of a Type Ia supernova depends upon the mass and central density of the white dwarf before it explodes. But how could these values be measured? After all, we typically only discover these stars after they explode. Fortunately, a new study in The Astrophysical Journal Letters shows how it can be done.
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Brain

Cleveland Clinic-led study identifies how COVID-19 linked to Alzheimer's disease-like cognitive impairment


Cleveland Clinic
Thu, 10 Jun 2021 00:00 UTC
Feixiong Cheng, Ph.D.
© UnknownFeixiong Cheng, Ph.D.
A new Cleveland Clinic-led study has identified mechanisms by which COVID-19 can lead to Alzheimer's disease-like dementia. The findings, published in Alzheimer's Research & Therapy, indicate an overlap between COVID-19 and brain changes common in Alzheimer's, and may help inform risk management and therapeutic strategies for COVID-19-associated cognitive impairment.

Reports of neurological complications in COVID-19 patients and "long-hauler" patients whose symptoms persist after the infection clears are becoming more common, suggesting that SARS-CoV-2 (the virus that causes COVID-19) may have lasting effects on brain function. However, it is not yet well understood how the virus leads to neurological issues.

Feixiong Cheng, Ph.D., assistant staff in Cleveland Clinic's Genomic Medicine Institute and lead author on the study says:
"While some studies suggest that SARS-CoV-2 infects brain cells directly, others found no evidence of the virus in the brain. Identifying how COVID-19 and neurological problems are linked will be critical for developing effective preventive and therapeutic strategies to address the surge in neurocognitive impairments that we expect to see in the near future."
In the study, the researchers harnessed artificial intelligence using existing datasets of patients with Alzheimer's and COVID-19. They measured the proximity between SARS-CoV-2 host genes/proteins and those associated with several neurological diseases where closer proximity suggests related or shared disease pathways. The researchers also analyzed the genetic factors that enabled SARS-COV-2 to infect brain tissues and cells.
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Galaxy

Supermassive black holes affect the universe beyond the bounds of their own galaxies

Mike McRae
Science Alert
Sat, 12 Jun 2021 09:13 UTC
galaxy
© Gabriel Pérez Díaz, SMM/IAC and Dylan Nelson/Illustris-TNGSatellite galaxies around a central galaxy.
They are the hot-headed tyrants that drive the evolution of the cosmos. Black holes so large, so powerful, the energy spilled from their swirling cloaks can define the landscape of nurseries and graveyards of stars in the galaxy surrounding them.

Even with masses equal to billions of suns, these gargantuan objects are still mere pinpricks in the vast galactic core, making a recent discovery of just how far their power might reach all the more surprising.

A team of astronomers and astrophysicists from around the globe have uncovered signs that the supermassive black holes in the hearts of many galaxies not only affect the distribution of stars in their own immediate surroundings but shape those of nearby galaxies as well.

Comment: A recent study revealed that galaxies throughout our universe are surprisingly similar, and this may be because the same forces involved in their formation are, rather than working in isolation, in some way connected: And check out SOTT radio's:

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Sun

Best of the Web: Stunning photos show solar eclipse as a 'ring of fire' over Canada and US Northeast

Josh K. Elliott
Global News
Thu, 10 Jun 2021 06:45 UTC
solar eclipse
© The Canadian press/Frank GunnAn annular solar eclipse rises over the skyline of Toronto on Thursday, June 10, 2021.
The sun and moon combined to create a dazzling ring of fire over northern Canada early Thursday during a rare annular solar eclipse that was at least partially visible across much of the country.

Early risers captured spectacular footage of the eclipse, which played out around 6 a.m. over much of Canada.


Comment: See also:

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Chalkboard

Solar Cycle 25: Is a Termination Event imminent?

Dr.Tony Phillips
Space Weather
Thu, 10 Jun 2021 12:00 UTC
sun solar
© Mongta Studio/Shutterstock
Something big may be about to happen on the sun. "We call it the Termination Event," says Scott McIntosh, a solar physicist at the National Center for Atmospheric Research (NCAR), "and it's very, very close to happening."

If you've never heard of the Termination Event, you're not alone. Many researchers have never heard of it either. It's a relatively new idea in solar physics championed by McIntosh and colleague Bob Leamon of the University of Maryland - Baltimore County. According to the two scientists, vast bands of magnetism are drifting across the surface of the sun. When oppositely-charged bands collide at the equator, they annihilate (or "terminate"). There's no explosion; this is magnetism, not anti-matter. Nevertheless, the Termination Event is a big deal. It can kickstart the next solar cycle into a higher gear.

Comment: See also:

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Brain

Piece of mind? Man incapable of feeling fear after having part of his BRAIN surgically removed


RT
Fri, 11 Jun 2021 17:11 UTC
brain mri
© REUTERS/Rupak De Chowdhuri
A man who struggled with anxiety claims that he lost the ability to feel fear after undergoing brain surgery, giving him stoic powers when faced with life's many dangers, such as muggers and spiders.

Jody Smith, 32, says that he's not "afraid" of anything anymore - an unexpected result of having his right amygdala cut out. The New York City resident suffered from brief panic attacks that would occur several times throughout his day. The periodic nervousness led to a serious episode in which he blacked out and began crawling around his neighbor's yard. Smith says that he barely remembers the incident. After consulting with a specialist, he was diagnosed with epilepsy.

He spent two years trying to treat his seizures with medication, but to no avail. Brain surgery was his last hope. Before the procedure could go ahead, doctors implanted probes inside Smith's brain so they could locate where the seizures were coming from. Smith was then instructed to intentionally have a seizure so that his doctors could pinpoint the area of his brain that needed to be scooped out. He said that he purposefully "tortured" himself, mostly by playing loud music and depriving himself of sleep, in hopes of triggering an epileptic reaction. At one point his doctors even encouraged him to drink beer to accelerate the process.
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Comet 2

New Comet C/2021 K2 (MASTER)

Ernesto Guido
Remanzacco Blogspot
Thu, 10 Jun 2021 18:00 UTC
CBET 4975 & MPEC 2021-L89, issued on 2021, June 09, announce the discovery of a new comet (magnitude ~19.0) on CCD images taken on May 23.0 UT with the "Mobile Astronomical System of the Telescope-Robots" (MASTER) auto-detection system (double 0.40-m f/2.5 reflector) at the South African Astronomical Observatory. The object was reported by MASTER as a new NEO candidate and has been found to show cometary activity by CCD astrometrists elsewhere. The new comet has been designated C/2021 K2 (MASTER).

Stacking of 35 unfiltered exposures, 120 seconds each, obtained remotely on 2021, June 02.4 from X02 (Telescope Live, Chile) through a 0.61-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 15" arcsecond in diameter elongated toward PA 180 (Observers E. Guido, M. Rocchetto, E. Bryssinck, M. Fulle, G. Milani, C. Nassef, G. Savini, A. Valvasori).

Our confirmation images (click on the images for a bigger version; made with TYCHO software by D. Parrott)

Comet C/2021 K2 (MASTER)
© Remanzacco Blogspot
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Cassiopaea

Hundreds of extragalactic fast radio bursts detected by single telescope in Canada

Michelle Starr
Science Alert
Wed, 09 Jun 2021 12:00 UTC
Fast Radio Burst
© B. Marcote et al. / Nature 2020This black-and-white Image shows further detail on the FRB's host galaxy. The FRB's position is marked. The inset zooms in on the star-forming region, showing it in higher contrast. Here, the FRB's position is marked with a red circle.
In just its first year of operations, a Canadian radio telescope has quadrupled the number of detections of strange cosmic signals known as extragalactic fast radio bursts.

Between 2018 and 2019, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) detected 535 new signals. The new, expanded fast radio burst (FRB) catalog will allow scientists to better analyze statistical data.

In turn, this will help us to understand where these mysterious bursts originate, and use them as a tool to understand the wider Universe.

"Before CHIME, there were less than 100 total discovered FRBs; now, after one year of observation, we've discovered hundreds more," said astrophysicist Kaitlyn Shin of MIT and the CHIME collaboration.

Comment: See also:

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Telescope

'Weird' exoplanet TOI-1231 b has 'unknown' atmosphere, might aid in hunt for alien life

Svetlana Ekimenko
Sputnik
Thu, 10 Jun 2021 17:00 UTC
exoplanet
© NASA/JPL-CaltechArtist’s rendering of TOI-1231 b, a Neptune-like planet about 90 light-years away from Earth.
The planet, some 90 light-years away from Earth, has a temperature similar to our own planet, exciting scientists.

A recently-discovered planet is intriguing scientists in their hunt for extraterrestrial life.

Exoplanet TOI-1231 b, orbiting a red dwarf star every 24 days, was found by researchers from Nasa's Jet Propulsion Laboratory and the University of New Mexico to have an atmosphere approximately 330 Kelvin or 140 degrees Fahrenheit. In layman terms, this makes it one of the coolest small exoplanets accessible for atmospheric studies out of any discovered before.

Comment: More from NASA's report:
The planet's red-dwarf star, though small, is quite bright in the infrared part of the light spectrum, or light beyond the red end of the spectrum that can't be seen with the naked eye. It is, however, ideal for investigation by Hubble and Webb. Also helpful: From our perspective on Earth, TOI-1231 b crosses the face of its star, which allowed its detection in the first place by NASA's Transiting Exoplanet Survey Satellite (TESS). And that crossing, called a "transit," takes nearly 3 ½ hours - plenty of time to capture and analyze starlight shining through the planet's atmosphere.

Fun facts: We might see evidence of clouds (perhaps even made of water) in this planet's atmosphere. And because this star-and-planet system is moving at a high velocity away from Earth, hydrogen atoms escaping from the planet's atmosphere might be readily detected. In other words, the planet could turn out to have a tail.

In general, such atoms are almost impossible to detect even when using space-based facilities; their presence is masked both by the outer wisps of Earth's atmosphere and by interstellar gas. But the TOI-1231 system is moving so quickly that escaping hydrogen atoms are shifted out of phase with the blocking material, where they could be detected by telescopes like Hubble.


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Cassiopaea

First evidence of cell membrane molecules in space


Astronomy
Fri, 28 May 2021 12:00 UTC
membrane
© Kateryna Kon/Shutterstock
The origin of life is one the great unanswered questions in science. One piece of this puzzle is that life started on Earth 4.5 billion years ago, just a few hundred million years after the formation of the Solar System, and involved numerous critical molecular components. How did all these components come to be available so quickly?

One potential explanation is that the Earth was seeded from space with the building blocks for life. The idea is that space is filled with clouds of gas and dust that contain all the organic molecules necessary for life.

Indeed, astronomers have observed these buildings blocks in interstellar gas clouds. They can see amino acids, the precursors of proteins and the machinery of life. They can also see the precursors of ribonucleotides, molecules that can store information in the form of DNA.

Comment: See also: And check out SOTT radio's:

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