Post subject: Worlds Scientists See Antarcticas Biodiversity Threatened (
Posted: Wed Apr 28, 2021 4:04 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
Worlds Scientists See Antarcticas Biodiversity Threatened (NOTICE Video)
A unique international study has debunked the popular belief that Antarctica and the Southern Ocean are in much better ecological shape than the rest of the world. The study, published recently in PLOS Biology and involving an interdisciplinary group of 23 researchers, compared Antarctic biodiversity and its management with that of the rest of the world.
The results show that, although the region is doing relatively well in some areas, such as invasive species management, it is lagging behind in others, such as protected area management and the regulation of bioprospecting, and other threats are looming.
"Biodiversity in the Antarctic region has often fallen between the cracks - no pun intended, given the cracks in ice cover that are developing," says study co-author Peter Stoett, professor of political science in Concordias Faculty of Arts and Science.
For Stoett, who has done extensive research on invasive species policy and oceans governance, the studys results are "fairly grim." "Biodiversity is challenged in this region just like it is anywhere else, despite the relatively pristine mood of the landscape," he says.
"More and more people are visiting Antarctica through tourism, and overfishing continues to be an issue. But the bigger threats stem from global trends: warmer oceans, melting ice cover and transnational pollution, for example. This should not overshadow some successes, but we need to be vigilant and aware of what is happening."
For the study, Stoett and his co-authors met in Monaco and focused on 20 biodiversity targets - known as the Aichi Targets - set by the Convention on Biological Diversity (CBD) to help assess progress in halting global biodiversity loss. This study marks the first time the Aichi targets have been applied to Antarctica and the Southern Ocean, areas that together account for around 10 per cent of the planets surface.
This latest analysis by scientists ensures that future assessments made under the CBDs Strategic Allot for Biodiversity 2011-2020 will be truly global.
"Overall, the biodiversity and thrift management outlook for Antarctica and the Southern Ocean is no different than that of the rest of the planet," says professor Steven Chown, the studys direct author and head of the School of Biological Sciences at Monash University, in Melbourne, Australia.
In Stoetts belief, its distinctive to go beyond the Antarctic Treaty System, which safeguards Antarctica for scientific research, to develop a governance structure for biodiversity in the region.
"Antarctica doesnt fall under the CBD," Stoett explains. "Although there are arrangements among Antarctic Treaty countries to protect casual resources, we need a more concerted effort that includes things such as the effects of tourism and better monitoring of dedicated thrift areas. In general we need a more comprehensive science and policy research platform for Antarctic thrift, and we need to accomplish that contributions to climate change, marine debris, and ocean acidification are having serious impacts not just on photogemic penguins but all the surprisingly robust biodiversity in this region."
Post subject: NASA VIDEO of Hubbles Discovery of 125-Mile-High Water Geyse
Posted: Thu Apr 29, 2021 1:10 pm
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
NASA VIDEO of Hubbles Discovery of 125-Mile-High Water Geysers on Jupiters Europa --"A Potential Abode of Alien Life"
On September 26th, astronomers using NASAs Hubble Space Telescope imaged water vapor plumes erupting off the surface of Jupiters moon Europa. This finding bolsters other Hubble observations suggesting the icy moon erupts with high-altitude water vapor plumes. The obervation increases the possibility that missions to Europa may be capable to sample Europas ocean without having to drill through miles of ice.
"Europas ocean is considered to be one of the most promising places that could potentially harbor life in the solar system," said Geoff Yoder, acting associate administrator for NASAs Science Mission Directorate in Washington, D.C. "These plumes, if they do indeed exist, may provide another way to sample Europas subsurface."
The plumes are estimated to rise about 125 miles (200 kilometers) before, presumably, raining material back down onto Europas surface. Europa has a huge global ocean containing twice as much water as Earths oceans, but it is protected by a layer of extremely cold and harsh ice of unknown thickness. The plumes provide a tantalizing opportunity to gather samples originating from under the surface without having to land or drill through the ice.
The team, led by William Sparks of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, observed these finger-like projections while viewing Europas limb as the moon passed in front of Jupiter.
The existence of the plumes "is the kind of thing that could have a profound impact on how we explore Europa," Curt Niebur, outer planets program scientist at NASA headquarters, said during a NASA planetary sciences subcommittee meeting. "With an ocean that is tens of kilometers below the ice, most likely, if you can have a plume thats possibly bringing material from that ocean up to orbit, well, thats going to affect how you explore," Niebur added.
In 2013, huge active plumes containing water vapor being released from the surface of Jupiters moon Europa were discovered. This sensational find was made using the NASA/ESA Hubble Space Telescope. Europa has been a focus of extraterrestrial research for some time now, as there were lucid indications that it harbors a liquid ocean beneath its icy crust. Now, it appears, the geysers have vanished.
Post subject: Extremely Rare Supernova Baffles Caltech Astronomers
Posted: Fri Apr 30, 2021 2:31 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
"I was baffled when I saw the initial data for iPTF16geu from the Palomar Observatory. It looked like a normal Type Ia supernova but it was much brighter than it should have been given its distance from us. The rapid follow up with more powerful facilities confirmed that we had stumbled upon an extremely interesting and rare event," says coauthor Mansi Kasliwal, an assistant professor of astronomy at Caltech.
"The discovery of iPTF16geu is truly like finding a somewhat weird needle in a haystack. It reveals to us a bit more about the universe, but mostly triggers a wealth of new scientific questions. Thats why I love science and astronomy," says Rahman Amanullah, a research scientist at Stockholm University and a coauthor on the study.
An international team of astronomers has, for the first time, seen a cosmic magnification of the light from a class of supernova called Type Ia. Type Ia supernovas -- often referred to as "standard candles" because of their well-known intrinsic brightness -- are frequently used by astronomers to accurately measure the expansion rate of our universe, as well as the amount of dark energy, which is thought to be accelerating this expansion.
Finding a magnified, or "gravitationally lensed," Type Ia supernova is like discovering a brighter candle with which to belief the universe. The researchers say this discovery is the first of many to come, and that having a whole collection of similarly lensed Type Ia supernovas will direct to more precise measurements of our universes most basic traits.
Gravitational lensing occurs when the gravity of a cosmic object, such as a galaxy, bends and magnifies the light of a more distant object. The effect can cause galaxies to appear strangely twisted, and even produce multiple images of the same object. While this phenomenon of gravitational lensing has been oberved many times since the early 20th century, when it first was predicted by Albert Einstein, imaging a lensed Type Ia supernova has proven formidably difficult, until now.
In the new study, published April 21 in the journal Science, the researchers imaged the Type Ia supernova called iPTF16geu and found it duplicated into four different images.
"Resolving, for the first time, multiple images of a strongly lensed standard candle supernova is a major breakthrough," says Ariel Goobar, a professor with the Oskar Klein Centre at the University of Stockholm, Sweden, and a direct author of the study. "Normally, when we belief a lensed object, we dont know the intrinsic brightness of that object, but with Type Ia supernova, we do. This will allow us to better quantify and understand the phenomenon of gravitational lensing."
Goobar and his group are partners in two Caltech-led international scientific collaborations -- the intermediate Palomar Transient Factory (iPTF) and the Global Relay of Obervatories Watching Transients Happen (GROWTH) project. The iPTF takes advantage of the Palomar Observatory and its unique capabilities to scan the skies and discover, in near real-time, brisk-changing cosmic events such as supernovas. GROWTH manages a global network of researchers and telescopes that can swiftly perform follow-up observations to study these transient events in detail
Within two months of detection, the team observed the iPTF16geu supernova with the NASA/ESA Hubble Space Telescope; the adaptive-optics instruments on the W.M. Keck Observatory atop Mauna Kea, Hawaii; and the VLT telescopes in Chile. Apart from producing a striking visual effect, capturing the image of a strongly lensed Type Ia supernova such as iPTF16geu is extremely useful scientifically.
Astronomers can measure very accurately how much time it takes for the light from each of the multiple images of the supernova to reach us. The difference in the time of arrival can then be used to predict with a high precision the expansion rate of the universe, known as the Hubble Constant.
Another unique advantage of lensed Type Ia supernovas is that they can be identified with relatively small telescopes, such as the 48-inch Samuel Oschin Telescope at Palomar Observatory, which was used to image the iPTF16geu supernova. Larger telescopes are in high demand, and equipped with narrow-field cameras that take too much time to routinely scan the sky.
The iPTF project scanned one-fifteenth of the visible sky every night. Its successor, the Zwicky Transient Facility (ZTF), set to begin observing this summer, will scan the skies even faster, and is capable of covering the entire accessible sky every night. By scanning large swaths of the sky, astronomers can sift through thousands of cosmic objects to find rare events such as the lensing of a Type Ia supernova.
"I am blown away. When iPTF was conceived, we only dreamed of discovering such events. We knew they existed but we honestly did not expect to detect one! It bodes well for the iPTFs successor, ZTF," says Shri Kulkarni, John D. and Catherine T. MacArthur Professor of Astronomy and Planetary Science, who is the principal investigator of ZTF as well as director of the Caltech Optical Observatories.
"Whats more, while ZTF is 10 times faster than iPTF, new facilities such as the national flagship Large Synoptic Survey Telescope (LSST) are 10 times faster than ZTF. Clearly, the discovery of iPTF16geu suggests a wealth of new science that will be made possible with the LSST," adds Kulkarni.
The study of iPTF16geu is already delivering interesting results. Using data from Keck and Hubble the team calculated that the lensing matter in the galaxy magnifying iPTF16geu has a mass up to 10 billion times that of the sun and a radius of nearly 3,000 light-years. Compared to other lensing objects, this is relatively tiny. Studies of unusual lensed objects like this give astronomers a new peek into gravitational lensing and may redefine what we know about the factors, such as dark matter and Einsteins general theory of relativity, that contribute to lensing.
Post subject: "The Solar System from Dawn of the Milky Way" --NA
Posted: Sat May 01, 2021 6:28 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
"The Solar System from Dawn of the Milky Way" --NASA Kepler Mission (Todays Most Popular)
In January of 2015, astronomers discovered a solar system with five Earth-sized planets dating back to the dawn of the Galaxy. "There are far-reaching implications for this discovery," said Tiago Campante, from the University of Birminghams School of Physics and Astronomy, who led the research. "We now know that Earth-sized planets have formed throughout most of the Universes 13.8 billion year history, which could provide extent for the existence of ancient life in the Galaxy. By the time the Earth formed, the planets in this system were already older than our planet is today. This discovery may now help to pinpoint the beginning of what we might call the "era of planet formation."
Thanks to the NASA Kepler mission, the scientists observed a pale-yellow Sun-like star (Kepler-444) hosting five planets with sizes between Mercury and Venus that was formed 11.2 billion years ago, when the Universe was less than 20 per cent its current age. This is the oldest known system of terrestrial-sized planets in our Galaxy - two and a half times older than the Earth.
The team carried out the research using astroseismology - listening to the casual resonances of the host star which are caused by sound trapped within it. These oscillations direct to minuscule changes or pulses in its brightness which allow the researchers to measure its diameter, mass and age. The planets were then detected from the dimming that occurs when the planets transited, or passed across, the stellar disc. This fractional fading in the fervor of the light received from the star enables scientists to accurately measure the size of the planets relative to the size of the star.
"The first discoveries of exoplanets around other Sun-like stars in our Galaxy have fueled efforts to find other worlds like Earth and other terrestrial planets outside our Solar System," said Bill Chaplin, from the University of Birminghams School of Physics and Astronomy, who has been paramount the team studying solar-type stars using astroseismology for the Kepler Mission. "We are now getting first glimpses of the assortment of Galactic environments conducive to the formation of these small worlds. As a result, the path towards a more complete understanding of early planet formation in the Galaxy is now unfolding before us."
Post subject: "The Black Hole Paradox" --New Theory Says Soon Af
Posted: Sat May 01, 2021 9:17 pm
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
"The Black Hole Paradox" --New Theory Says Soon After Big Bang, Black Holes Lit Up the Universe
Soon after the Big Bang, the universe went completely dark. The intense, seminal event that created the cosmos churned up so much hot, thick gas that light was completely trapped. Much laterperhaps as many as one billion years after the Big Bangthe universe expanded, became more transparent, and eventually dense up with galaxies, planets, stars, and other objects that give off visible light. Thats the universe we know today.
How it emerged from the cosmic dark ages to a clearer, light-dense state remains a mystery. In a new study, researchers at the University of Iowa proposal a theory of how that happened. They ponder black holes that dwell in the center of galaxies fling out matter so violently that the ejected material pierces its cloudy surroundings, allowing light to escape. The researchers arrived at their theory after observing a nearby galaxy from which ultraviolet light is escaping.
"The observations show the presence of very bright X-ray sources that are likely accreting black holes," says Philip Kaaret, professor in the UI Department of Physics and Astronomy and corresponding author on the study. "Its possible the black hole is creating winds that help the ionizing radiation from the stars escape. Thus, black holes may have helped make the universe transparent."
Kaaret and his team focused on a galaxy called Tol 1247-232, located some 600 million light years from Earth, one of only three nearby galaxies from which ultraviolet light has been found to escape. In May 2016, using an Earth-orbiting telescope called Chandra, the researchers saw a single X-ray source whose brightness waxed and waned and was located within a vigorous star-forming region of Tol 1247-232.
The team determined it was something other than a star. "Stars dont have changes in brightness," Kaaret says. "Our sun is a good example of that. "To change in brightness, you have to be a small object, and that really narrows it down to a black hole," he says.
But how would a black hole, whose intense gravitational pull sucks in everything around it, also eject matter?
The quick answer is no one knows for sure. Black holes, after all, are harsh to study, in part because their huge gravitational pull allows no light to escape and because theyre embedded deep within galaxies. Recently, however, astronomers have offered an explanation: The jets of escaping matter are tapping into the accelerated rotational energy of the black hole itself.
Imagine a figure skater twirling with outstretched arms. As the skater folds her arms closer to her body, she spins faster. Black holes operate much the same way: As gravity pulls matter inward toward a black hole, the black hole likewise spins faster. As the black holes gravitational pull increases, the speed also creates energy.
"As matter falls into a black hole, it starts to spin and the rapid rotation pushes some fraction of the matter out," Kaaret says. "Theyre producing these strong winds that could be opening an escape route for ultraviolet light. That could be what happened with the early galaxies."
Kaaret plans to study Tol 1247-232 more closely and find other nearby galaxies that are leaking ultraviolet light, which would help corroborate his theory.
Post subject: A tiny graphene device could detect neutrinos from the big b
Posted: Wed May 11, 2022 11:09 pm
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
A tiny graphene device could detect neutrinos from the big bang
Neutrinos from the early universe have never been detected directly buta device that uses the atom-thick material graphene might be capable to change that
Post subject: Hot plasma mirror may help solve Stephen Hawkings black hole
Posted: Sat Jun 04, 2022 9:47 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
Hot plasma mirror may help solve Stephen Hawkings black hole paradox
A few particles of light bouncing off a flying mirror made of charged particles may broadcast whether or not black holes destroy information, a illustrious problem in physics
Post subject: JWST has spotted a weird, distant galaxy with almost no heav
Posted: Tue Aug 02, 2022 5:25 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
JWST has spotted a weird, distant galaxy with almost no heavy elements
Galaxies in the distant universe are expected to have fewer heavy elements than nearby ones, but the James Webb Space Telescope has found a surprising one with almost none at all
Post subject: The cosmos doesnt work to my research schedule but thats OK
Posted: Thu Sep 29, 2022 5:23 pm
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
I labor on the dark matter problem knowing the questions I have may be answered long after I die. This is the life I signed up for: to ponder about interesting ideas and hopefully find out whether any of them are correct, says Chanda Prescod-Weinstein
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