Space Thread

spaminator

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Asteroids rarely discovered prior to impact with earth
Author of the article:Liz Braun
Publishing date:Mar 15, 2022 • 14 hours ago • 2 minute read • Join the conversation
An asteroid hit the Earth a few days ago — with only two hours warning
An asteroid hit the Earth a few days ago — with only two hours warning PHOTO BY @SPACEDOTCOM /Toronto Sun
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Will we all be killed by falling asteroids?

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An asteroid hit the Earth a few days ago — with only two hours warning, according to the New York Post.

Hungarian astronomer Krisztian Sarneczky, at the Konkoly Observatory near Budapest, identified a small asteroid hurtling toward earth that eventually came down just north of Iceland.

Called 2022 EB5, the small object was moving at 18.5 kilometres a second, a speed so intense that the asteroid vaporized upon entering Earth’s atmosphere. It’s unknown whether any pieces of the asteroid actually struck the ground.

But since some people in Iceland reported hearing a boom and seeing a flash of light, however, the International Meteor Organization has sought witnesses.

If the small meteor had struck the Earth, it would not have caused much damage, given its size.

According to earthsky.org, Sarneczky’s discovery of the meteor before it entered the Earth’s atmosphere is only the fifth time an asteroid has been discovered before impact.

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This prompted astronomer Marian Rudnyk to tweet that the rarity of these pre-impact discoveries “shows just how dangerous they are & how vulnerable we are.”

It’s a theme Hollywood has explored in the past.

So has NASA. A recent report from the space agency outlines the results of a simulated asteroid impact response, sponsored by NASA and the Federal Emergency Management Agency (FEMA), and hosted by the Johns Hopkins Applied Physics Laboratory.

Over two days, the exercise determined how well federal, state, and local agencies could work together and coordinate an effective response.

“This specific exercise marked the first time an end-to-end simulation of this type of disaster was studied, to include assessing a scenario from discovery of the asteroid impact threat through the aftermath effects of its hypothetical impact with Earth,” said Lindley Johnson, planetary defence officer at NASA Headquarters.

“An asteroid impact to our planet is potentially the only natural disaster humanity is capable of accurately predicting and preventing,” he said.

That might be premature.

Later this year, NASA’s Double Asteroid Redirection Test (DART) mission will demonstrate (via kinetic impact deflection) the technology for defending Earth against potential asteroid impacts.

Still, technology like DART will only work if any threat is discovered with enough warning time, which runs to several years.
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spaminator

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After killer asteroid, mammals got bigger before they got smarter
Author of the article:Reuters
Reuters
Will Dunham
Publishing date:Mar 31, 2022 • 16 hours ago • 3 minute read • Join the conversation
A crescent view of the Earth as seen by Apollo 11 astronauts on their return from the moon.
A crescent view of the Earth as seen by Apollo 11 astronauts on their return from the moon. PHOTO BY NASA /handout
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WASHINGTON — In the aftermath of the asteroid impact 66 million years ago that doomed the dinosaurs, it appears that brawn was more important than brains for the mammals that managed to survive the calamity and conquer a changed world.

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Researchers said on Thursday an analysis of fossils of mammals from the Paleocene Epoch – spanning the 10 million years after the asteroid wiped out three-fourths of Earth’s species – found that while their bodies got much bigger, their brain size relative to body mass actually declined.

The findings contradict the notion that it was intelligence that drove mammals – bit players during the age of dinosaurs – to become the planet’s new rulers following the mass extinction at the end of the Cretaceous Period.

“The process to get large brains to emerge in mammals after the extinction was much slower than we previously thought,” said Ornella Bertrand, a postdoctoral researcher in mammal paleontology at the University of Edinburgh and lead author of the study published in the journal Science.

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The researchers performed CT scans on fossils of 28 Paleocene mammal specimens and 96 from the subsequent Eocene Epoch, spanning 56-34 million years ago. They assessed brain size and the development of specific cerebral components. Brain growth, they found, kicked in during the Eocene, along with a change in the importance of various functions.

“Contrary to our expectations, the mammals that survived the asteroid and outlasted the dinosaurs were fairly dim-witted. They didn’t have near the brainpower of modern-day mammals – and keen intelligence came only many millions of years later,” University of Edinburgh paleontologist and study co-author Steve Brusatte said.

Mammals began to evolve greater body size almost immediately after the mass extinction that eliminated the dinosaurs, aside from their bird descendants. Before it, mammals typically were about the size of a shrew. During the Paleocene, some got as big as bears.

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“When the non-avian dinosaurs went extinct, an unprecedented opportunity became available for mammals, and they started invading the ecological niches left emptied by becoming bigger,” Bertrand said.

The researchers learned that the sense of smell – gauged by the development of the brain’s olfactory bulbs – was crucial for Paleocene mammals as they seized new ecological roles. During the Eocene, other capabilities such as the greater integration of vision, hearing, memory and motor control – tied to neocortex development – became more critical for survival.

“There is a cost associated in having a large brain. The energy allocated to the brain represents 20% of the entire energy allocated to the body. So, the evolution of large brains might only occur when the benefit of having a large brain outweighs the cost of maintaining it,” Bertrand said.

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Mammals now boast the animal kingdom’s largest brains relative to body size. Their Eocene brain growth occurred as competition for resources intensified and complex behavior became vital for species survival, Bertrand said. Some archaic Paleocene lineages disappeared, supplanted by mammals more like those living today.

With dinosaur predators and plant-eaters gone, mammals began to fill these roles in the Paleocene, a time of evolutionary experimentation. Panther-sized Arctocyon, one of the mammals studied, bore large canine teeth and ate meat and possibly plants, too. Llama-sized herbivore Ectoconus, also studied, was heavily built with strong limbs and feet.

The study focused on placentals, by far the most common mammals. Fossils unearthed in recent years in New Mexico, Colorado and France provided insight into Paleocene mammals.

“Within 100,000 years after the extinction, species richness increased, and mammals rapidly became morphologically diverse,” Bertrand said. “Some Paleocene species were chunky overall, and quite different from the modern groups, while others lived in trees and may have been possible ancestors to primates – the group that much later includes humans. In the Paleocene, the mammals are doing their own thing.”
 

spaminator

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Hubble telescope spots Earendel, the most distant star on record
Author of the article:Reuters
Reuters
Will Dunham
Publishing date:Mar 31, 2022 • 17 hours ago • 3 minute read • Join the conversation
This detailed view highlights the star Earendel's position along a ripple in space-time (dotted line) that magnifies it and makes it possible for the star to be detected over such a great distance - nearly 13 billion light-years. Also indicated is a cluster of stars that is mirrored on either side of the line of magnification. The distortion and magnification are created by the mass of a huge galaxy cluster located in between Hubble and Earendel.
This detailed view highlights the star Earendel's position along a ripple in space-time (dotted line) that magnifies it and makes it possible for the star to be detected over such a great distance - nearly 13 billion light-years. Also indicated is a cluster of stars that is mirrored on either side of the line of magnification. The distortion and magnification are created by the mass of a huge galaxy cluster located in between Hubble and Earendel. PHOTO BY NASA, ESA, BRIAN WELCH (JHU), DAN COE (STSCI); IMAGE PROCESSING: NASA, ESA, ALYSSA PAGAN (STSCI) /Handout via REUTERS
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WASHINGTON — Using NASA’s Hubble Space Telescope, scientists have discovered the most distant individual star on record, a bright behemoth they nicknamed Earendel – Old English for “morning star” – because it existed during the dawn of the universe.

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Researchers said the star, very hot and blue in colour, was estimated at 50 to 100 times the mass of our sun, while being millions of times brighter. Its light travelled for 12.9 billion years before reaching Earth, meaning that the star existed when the universe was just 7% of its current age.

Earendel was born roughly 900 million years after the Big Bang event at the outset of the universe. It belonged to among the earliest generations of stars at a time when the universe was quite different than it is today.

“This really opens up a new window into those early days of the universe,” said astronomer Brian Welch of Johns Hopkins University in Baltimore, lead author of the research published this week in the journal Nature.

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“We’re seeing the star in the time period that is often referred to as Cosmic Dawn – when the first light in the universe was starting to turn on with these first stars and when the first galaxies are starting to form,” Welch added.

Explaining its nickname, Welch said the researchers figured that the “morning star” existing during the Cosmic Dawn period was “a good parallel.”

“It’s also for the ‘Lord of the Rings’ nerds out there,” he added, noting that Earendel is the same Old English word that author J.R.R. Tolkien used for inspiration for a character from his work “The Silmarillion” that becomes a star.

In observing objects as distant as Earendel, scientists are peering into the deep past because of the vast distance the light from the star traveled to reach Earth – in a sense, using Hubble as a time machine.

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“So normally when we look at very distant objects, what we’re seeing is the light from an entire galaxy – so millions of stars all blended together – and we’ve been able to see those out to even farther distances. But in this case, thanks to a very massive cluster of galaxies in the foreground, the light from this one star has just been very, very highly magnified, so we’re able to see this single star at a much greater distance,” Welch said.

The first Hubble images of Earendel were obtained in 2016, with 2019 follow-up observations. The researchers are hoping to study it further using the next-generation James Webb Space Telescope, due to become operational within months after being launched in December.

Welch said the researchers were surprised by the discovery, saying, “Yeah, there was definitely a period of wondering whether this could possibly be real.”

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Until now, the most distant single star on record was one nicknamed Icarus that existed 4 billion years after Earendel.

Earendel was probably much different than stars populating the universe today. Welch said it was likely composed mostly of hydrogen and helium, with perhaps trace amounts of heavier elements including carbon, nitrogen and oxygen.

Welch said the first stars formed roughly 100 million years after the Big Bang explosion and that perhaps one or two generations of stars had preceded Earendel’s formation.

Heavier elements did not exist until they were forged in the fusion caldrons of the cores of the initial generations of stars, then were blasted into space when these earliest stars exploded at the end of their life cycles.

Even though scientists on Earth can now see its light, Earendel itself certainly no longer exists, with such huge stars having relatively short lifespans, Welch said. It existed for perhaps a few hundred million years before dying in a supernova explosion. “Massive stars tend to live fast and die young,” Welch said.
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spaminator

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Gigantic Jupiter-like alien planet observed still 'in the womb'
Author of the article:Reuters
Reuters
Will Dunham
Publishing date:Apr 04, 2022 • 17 hours ago • 3 minute read • Join the conversation
An artist's illustration shows a massive, newly forming exoplanet called AB Aurigae b.
An artist's illustration shows a massive, newly forming exoplanet called AB Aurigae b. PHOTO BY NASA, ESA, JOSEPH OLMSTED (STSCI) /Handout via REUTERS
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WASHINGTON — Scientists have observed an enormous planet about nine times the mass of Jupiter at a remarkably early stage of formation – describing it as still in the womb – in a discovery that challenges the current understanding of planetary formation.

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The researchers used the Subaru Telescope located near the summit of an inactive Hawaiian volcano and the orbiting Hubble Space Telescope to detect and study the planet, a gas giant orbiting unusually far from its young host star. Gas giants are planets, like our solar system’s largest ones Jupiter and Saturn, composed mostly of hydrogen and helium, with swirling gases surrounding a smaller solid core.

“We think it is still very early on in its ‘birthing’ process,” said astrophysicist Thayne Currie of the Subaru Telescope and the NASA-Ames Research Center, lead author of the study published on Monday in the journal Nature Astronomy. “Evidence suggests that this is the earliest stage of formation ever observed for a gas giant.”

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It is embedded in an expansive disk of gas and dust, bearing the material that forms planets, that surrounds a star called AB Aurigae located 508 light years – the distance light travels in a year, 9.5 trillion km – from Earth. This star got a fleeting moment of fame when its image appeared in a scene in the 2021 film “Don’t Look Up.”

About 5,000 planets beyond our solar system, or exoplanets, have been identified. This one, called AB Aur b, is among the largest. It is approaching the maximum size to be classified as a planet rather than a brown dwarf, a body intermediate between planet and star. It is heated by gas and dust falling into it.

Planets in the process of formation – called protoplanets – have been observed around only one other star.

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Almost all known exoplanets have orbits around their stars within the distance that separates our sun and its most faraway planet Neptune. But this planet orbits three times as far as Neptune from the sun and 93 times Earth’s distance from the sun.

Its birth appears to be following a different process than the standard planetary formation model.

“The conventional thinking is that most – if not all – planets form by slow accretion of solids onto a rocky core, and that gas giants go through this phase before the solid core is massive enough to start accreting gas,” said astronomer and study co-author Olivier Guyon of the Subaru Telescope and the University of Arizona.

In this scenario, protoplanets embedded in the disk surrounding a young star gradually grow out of dust- to boulder-sized solid objects and, if this core reaches several times Earth’s mass, then begin accumulating gas from the disk.

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“This process cannot form giant planets at large orbital distance, so this discovery challenges our understanding of planet formation,” Guyon said.

Instead, the researchers believe AB Aur b is forming in a scenario in which the disk around the star cools and gravity causes it to fragment into one or more massive clumps that form into planets.

“There’s more than one way to cook an egg,” Currie said. “And apparently there may be more than one way to form a Jupiter-like planet.”

The star AB Aurigae is about 2.4 times more massive than our sun and almost 60 times brighter. It is about 2 million years old – an infant by stellar standards – compared to about 4.5 billion years for our middle-aged sun. The sun early in its life also was surrounded by a disk that gave rise to Earth and the other planets.

“New astronomical observations continuously challenge our current theories, ultimately improving our understanding of the universe,” Guyon said. “Planet formation is very complex and messy, with many surprises still ahead.”
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spaminator

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Scientists think they found asteroid that ended dinosaurs on Earth
Author of the article:postmedia News
Publishing date:Apr 11, 2022 • 11 hours ago • 1 minute read • Join the conversation
Scientists at a site in North Dakota believe they’ve found pieces of an asteroid that hit Earth about 66 million years ago off the Yucatan Peninsula that led to the slow extinction of dinosaurs.
Scientists at a site in North Dakota believe they’ve found pieces of an asteroid that hit Earth about 66 million years ago off the Yucatan Peninsula that led to the slow extinction of dinosaurs. PHOTO BY ISTOCK /GETTY IMAGES
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Dino-mite!

Scientists at a site in North Dakota believe they’ve found pieces of an asteroid that hit Earth about 66 million years ago off the Yucatan Peninsula that led to the slow extinction of dinosaurs.

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When the asteroid struck, it sent molten debris into the air that later cooled into “spherules of glass,” which millions of years later were discovered on the North Dakota site known as Tanis preserved in amber, according to the New York Times.

Fragment tests show they not only contained unmelted rock but portions of limestone crust from the asteroid crater thousands of miles away.

There were also high amounts of iron, nickel, and chromium which are found in asteroid material.

“Every single speck that takes away from this beautiful clear glass is a piece of debris,” said Robert DePalma, an adjunct professor and University of Manchester graduate, during a speech at the NASA Goddard Space Flight Center this week, according to the Times.

“To see a piece of the culprit is just a goose-bumpy experience.”

DePalma’s findings have not undergone a peer-review yet but his supervisor, Professor Phil Manning told BBC he also believes the pieces are from the dinosaur-ending asteroid according to people.com.

“We were able to pull apart the chemistry and identify the composition of that material,” Manning said.

“All the evidence, all of the chemical data from that study suggests strongly that we’re looking at a piece of the impactor; of the asteroid that ended it for the dinosaurs.”
 

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Are we shadows?: The disturbing conclusion black holes imply about your reality

 

spaminator

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Weekend fireball may have scattered meteorites near Lake Simcoe: Researcher
Western astronomers run a camera network that searches the sky for such meteors.

Author of the article:Free Press staff
Publishing date:Apr 18, 2022 • 12 hours ago • 1 minute read • Join the conversation
A fireball (brightest light) observed by the CA000P Global Meteor Network camera in Bowmanville. Additional streaks are lens reflections. (Photo by Miguel Preciado)
A fireball (brightest light) observed by the CA000P Global Meteor Network camera in Bowmanville. Additional streaks are lens reflections. (Photo by Miguel Preciado)
A fireball that dropped from space Sunday night may have scattered meteorites when it fell near the eastern shore of Lake Simcoe, a Western University researcher says.


Scientists discover how caffeine protects against cardiovascular disease


“Analysis of the video data suggests that fragments of the meteor are likely to have made it to the ground . . . just north of the town of Argyle,” the university said in a news release Monday.

Denis Vida, a Western researcher who studies meteors, said, “This fireball was particularly significant because it was moving slowly, was on an asteroidal orbit, and ended very low in the atmosphere. These are all good indicators that material survived.”

The fireball was observed at 11:37 p.m. Sunday, the university says.

Western astronomers run a camera network that searches the sky for such meteors. More than a dozen of the cameras, part of the Southern Ontario Meteor Network, took pictures of the fireball plummeting to Earth north of Toronto, Vida said.


Vida estimates the mass of the object to be about 10 kilograms, and he expects tens or as much as hundreds of grams of material may have fallen to Earth. These fragments are valuable to researchers because they provide clues about how the solar system formed and developed.

Tiny shards of meteors can be recognized by their dark, often scalloped texture. They are usually more dense than Earth rocks and often are attracted to magnets because of their metal content.

Under Canadian law, meteorites belong to the landowner where they are found. Western experts say it’s best to handle them as little as possible to preserve their scientific value, and place them in a plastic bag or aluminum foil.

Experts at the university and Royal Ontario Museum urge those in the area who saw or heard anything unusual Sunday night, or who may have found possible meteorites, to contact them at naturalhistory@rom.on.ca. Vida can be reached at dvida@uwo.ca.
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spaminator

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Jupiter's moon Europa could harbour life, study suggests
Author of the article:Reuters
Reuters
Will Dunham
Publishing date:Apr 19, 2022 • 20 hours ago • 3 minute read • Join the conversation
An artist's conception provided by Stanford University shows how double ridges on the surface of Jupiter's moon Europa may form over shallow, refreezing water pockets within the ice shell, in this handout image obtained by Reuters on April 18, 2022.
An artist's conception provided by Stanford University shows how double ridges on the surface of Jupiter's moon Europa may form over shallow, refreezing water pockets within the ice shell, in this handout image obtained by Reuters on April 18, 2022. PHOTO BY JUSTICE BLAINE WAINWRIGHT /Handout via REUTERS
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WASHINGTON — The uncanny resemblance between features on Europa’s frozen surface and a landform in Greenland that sits atop a sizable pocket of water are providing intriguing new indications that this moon of Jupiter may be capable of harbouring life.


A study published on Tuesday explored similarities between elongated landforms called double ridges that look like huge gashes across Europa’s surface and a smaller version in Greenland examined using ice-penetrating radar.

Double ridges are linear, with two peaks and a central trough between them.

“If you sliced through one and looked at the cross section, it would look a bit like the capital letter ‘M,'” said Stanford University geophysicist Riley Culberg, lead author of the study published in the journal Nature Communications.

Radar data showed that refreezing of liquid subsurface water drove the formation of Greenland’s double ridge. If Europa’s features form the same way, this could signal the presence of copious amounts of liquid water – a key ingredient for life – near the surface of this Jovian moon’s thick outer ice shell.


Imagery obtained by NASA’s Galileo spacecraft in 1996 and 1997 revealing the topography of the icy crust of Jupiter’s moon Europa, a computer-generated three-dimensional perspective (upper right), and a color-coded model accentuating elevations (lower right) are seen in this handout image obtained by Reuters on April 18, 2022.
Imagery obtained by NASA’s Galileo spacecraft in 1996 and 1997 revealing the topography of the icy crust of Jupiter’s moon Europa, a computer-generated three-dimensional perspective (upper right), and a color-coded model accentuating elevations (lower right) are seen in this handout image obtained by Reuters on April 18, 2022. PHOTO BY NASA/JPL/DLR /Handout via REUTERS
In the search for extraterrestrial life, Europa has attracted attention as one of the locales in our solar system that may be habitable, perhaps by microbes, owing to a global saltwater ocean detected deep beneath its ice shell. Innumerable water pockets closer to the surface would represent a second potential habitat for organisms.

“The presence of liquid water in the ice shell would suggest that exchange between the ocean and ice shell is common, which could be important for chemical cycling that would help support life,” Culberg said. “Shallow water in particular also means there might be easier targets for future space missions to image or sample that could at least preserve evidence of life without having to fully access the deep ocean.”


NASA’s robotic Europa Clipper spacecraft is scheduled for a 2024 launch to further investigate whether this moon possesses conditions suitable for life.

The shallow depth of Europa’s potential water pockets – perhaps within six-tenths of a kilomietre of the surface – also would place them near chemicals vital for the formation of life that may exist on its surface.

With a diameter of 1,940 miles (3,100 km), Europa is the fourth-largest of Jupiter’s 79 known moons, a bit smaller than Earth’s moon but bigger than the dwarf planet Pluto. Europa’s ocean may contain double the water of those on Earth. Life first emerged on Earth as marine microbes.

Europa’s double ridges, sometimes extending hundreds miles (km), generally are around 490-650 feet (150-200 metres) tall, with the peaks about three- to six-tenths of a mile (0.5-1 km) apart.


Scientists have debated how they formed. Culberg was struck by their resemblance to a landform he knew from northwestern Greenland, with peaks about 6.5 feet (2 metres tall), separated by about 160 feet (50 metres) and extending about a half mile (800 metres).

“The Greenland double ridge feature formed from the successive refreezing, pressurization and fracture of a near-surface water pocket. We see two ridges, rather than one, because the shallow water pocket was also split in two by a fracture filled with refrozen water,” Culberg said.

The water pocket in Greenland was about 50 feet (15 metres) below the surface, likely less than 33 feet (10 metres) thick and about a mile (1.6 km) wide.

If the same process spawned Europa’s many double ridges, each associated water pocket could boast a volume similar to Lake Erie, one of North America’s Great Lakes.

“Between having two potential habitats and the fact that double ridges – and the near-surface water bodies they may imply – are among the most common features on Europa’s surface, it makes this moon a very exciting candidate for habitability indeed,” Stanford geophysics professor and study co-author Dustin Schroeder added.
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spaminator

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Surprised astronomers find new type of star explosion - a micronova
Author of the article:Reuters
Reuters
Will Dunham
Publishing date:Apr 20, 2022 • 18 hours ago • 3 minute read • Join the conversation
This artist's impression shows a two-star system where stellar explosions called micronovae may occur.
This artist's impression shows a two-star system where stellar explosions called micronovae may occur. PHOTO BY EUROPEAN SOUTHERN OBSERVATORY/M. KORNMESSER, L. CALCADA /Handout via REUTERS
WASHINGTON — Astronomers have detected a previously unknown type of stellar explosion called a micronova involving thermonuclear blasts at the polar regions of a type of burned-out star called a white dwarf after it has siphoned material from a companion star.


The researchers said on Wednesday a micronova is by far the least powerful type of star explosions now known – less energetic than a blast called a nova in which a white dwarf’s entire surface blows up and tiny compared to a supernova that occurs during the death throes of some giant stars.

Micronovae are observed from Earth as bursts of light lasting about 10 hours. They were documented on three white dwarfs – one 1,680 light years away from Earth, one 3,720 light years away and one 4,900 light years away. A light year is the distance light travels in a year, 9.5 trillion km.

“The discovery was an unexpected surprise. It goes to show just how dynamic the universe is. These events are fast and sporadic. Finding them requires looking at the right place at the right time,” said astronomer Simone Scaringi of Durham University in England, lead author of the study published in the journal Nature.


White dwarfs, among the densest objects in the universe, result from the collapse of a dying star’s core. They have the mass of our sun but are about the size of Earth in diameter. Most stars, including the sun, are destined to end their existence in this form.

Some white dwarfs are part of what is called a binary system, in an orbit with another star.

Micronovae happen in very specific binary systems – with a white dwarf star possessing a strong magnetic field and a low-mass normal star. The white dwarf’s gravitational pull can strip hydrogen gas from the companion star’s surface. The hydrogen then flows toward the white dwarf’s magnetic poles, similar to how Earth’s magnetic field channels the solar wind to our planet’s magnetic poles, causing the auroras.


This artist’s impression shows a two-star system, with a white dwarf (in the foreground) and a companion star (in the background), where stellar explosions called micronovae may occur.
This artist’s impression shows a two-star system, with a white dwarf (in the foreground) and a companion star (in the background), where stellar explosions called micronovae may occur. PHOTO BY MARK GARLICK/EUROPEAN SOUTHERN OBSERVATORY /Handout via REUTERS
At the base of accumulating columns of gas at the white dwarf’s poles, pressure and temperature rise, causing thermonuclear fusion that converts hydrogen into helium.

“Under the conditions in which this is triggered, this fusion is explosive, and the micronova occurs: a thermonuclear ‘bomb’ goes off,” said astronomer and study co-author Paul Groot, who divides his time between Radboud University in the Netherlands and the University of Cape Town and South African Astronomical Observatory.

The explosion is localized and does not destroy the white dwarf. In fact, the micronova cycle can repeat itself.

“Only a very small percentage of the white dwarf participates in this explosion, roughly about one millionth of the surface area. Translated to the Earth this would be an area of about, say, the city of London,” Groot added.


Each micronova event burns through material the equivalent of one large asteroid, or just over one millionth of Earth’s mass, Scaringi said.

A micronova is similar to a nova, a thermonuclear explosion engulfing a white dwarf’s entire surface. With novae, the white dwarf lacks a strong magnetic field, meaning that hydrogen stolen from the companion star is distributed globally rather than concentrating at the poles. Novae can last for weeks or months, burning through about a million times more mass than micronovae, Scaringi said.

The researchers discovered the micronovae when analyzing data from NASA’s TESS space telescope. They used the European Southern Observatory’s Chile-based Very Large Telescope to confirm the explosions involved white dwarfs.

Some other types of stellar explosions include: a kilonova, when two neutron stars or a neutron star and a black hole merge; a hypernova, a kind of supernova involving a massive star exploding at end of its life cycle and collapsing to form a black hole; and a luminous red nova involving two stars merging.
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spaminator

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Two planets will appear to 'nearly collide' in the night sky this week
Author of the article:Washington Post
Washington Post
Matthew Cappucci, The Washington Post
Publishing date:Apr 26, 2022 • 17 hours ago • 4 minute read • Join the conversation

Early risers on Saturday will be treated to a planetary “conjunction” in the morning skies. NASA says the intermingling of Jupiter and Venus, which will only last two days, will make the planets appear to “almost collide.” The two celestial bodies are among the brightest objects currently present in the night sky.


While those with telescopes should easily be able to distinguish the two planets, there’s a chance that some naked-eye observers may witness a combined radiant overlap between the two.

The conjunction will be ongoing early on the morning of May 1, but, as the planets head their separate directions in the night sky, the duo will have swapped positions.

In addition to Venus and Jupiter, a trio of other planets will grace the skies, though they’ll probably only be visible for city skywatchers and stargazers with a telescope. In more rural areas, two of the other planets – Mars and Saturn – have already traced a perfect line as the solar system remains splayed out in a glorious splendor. They’ll continue to do so in the days ahead.


– – –

A “conjunction” occurs when two planets appear, from the vantage point of Earth, to swipe by one another in the sky. While there’s no specific metric that states how proximate they must be, the commonly accepted definition is within a couple of degrees. Conjunctions of Venus and Jupiter, the two most luminous planets in our skies, are known as “great conjunctions.”

On Dec. 21, 2020, the most spectacular great conjunction in 800 years brought Saturn and Jupiter just a tenth of a degree apart. For comparison, if you held your hand at arm’s length and closed one eye, the apparent width of your pinkie finger would be about a degree. Imagine a sliver of that. That’s about how close Jupiter came to nicking Saturn in 2020. It was the closest they’d been together since March 5, 1226, and the best great conjunction until 2080.


Technically speaking, there’s nothing to say one planet or celestial body can’t pass in front of another. It happens all the time with the Earth, sun and moon. When the moon fully obscures the sun and blocks sunlight from reaching Earth, it’s a total solar eclipse. Eclipses occur when objects are roughly the same apparent size in the sky.

Otherwise, a body that appears smaller may cross the face of a much larger-appearing body, resembling a small speck that intercedes as a blemish on whatever it’s blocking. That’s called a transit. Venus periodically transits in front of the sun, doing so every 243 years. Mercury’s transits are a bit more frequent, the last occurring on Nov. 11, 2019, with the next slated for Nov. 13, 2032. Those are the only two planets that let us witness a solar transit, since they have closer orbits to the sun than we Earthdwellers do.


Saturday morning’s show between Venus and Jupiter won’t be a “great” conjunction by the books, but it still will be “great” by virtue of being both scientifically captivating and visually stimulating.

Venus will appear brighter and on the lower right of the tangoing planets, while Jupiter sidesteps just a bit above and to the left.

– – –

Your best bet for enjoying the transit will be to look east before sunrise on Saturday, April 30. The predawn and twilight hours will be the best time to do so. That’s because Venus is the second-closest planet to the sun, so usually seeing it requires the sun to be relatively near in the sky – which is the case only at sunrise or sunset.

Venus is going to be about 92.9 million miles away from Earth on Saturday morning, or roughly the same distance as the sun. That may sound like a lot, but consider Jupiter. It’ll be 526.6 million miles away. Even though the two are more than 430,000,000 miles distant, they’ll appear close by just because of where they happen to be in their orbits.


You’ll be table to tell which one is Venus because it will be brighter and yellowish. That’s thanks to the thick sulfuric acid clouds that shroud its atmosphere, trapping heat and allowing the atmosphere to reach a scorching 900 plus degrees. (The atmosphere of Venus is also 90 times heavier than that of Earth, meaning that a person on the surface would be burned to death, crushed to death and poisoned to death all at once. Tourism to Venus is currently not recommended under current guidelines.)

Jupiter, on the other hand, may seem to have a reddish tinge to the naked eye. The gas giant spins every 10 hours, meaning every Earth day holds about 2.4 Jupiter days, but a “year” on Jupiter is actually 12 years long since it takes so long to orbit the sun.


On Sunday morning, Venus and Jupiter will still be flirting in proximity, but they’ll head their separate ways – Jupiter will rush up and right while Venus lays low to the horizon.

Both weekend days will also permit the viewing of Mars and Saturn under ideal conditions, but they’ll be much fainter and tougher to spot. Just trace a line up and right from Venus and Jupiter and you may run into them. If your skies are dark enough, it could make for a pretty special photo op.

As if that wasn’t enough, parts of South America will enjoy a partial solar eclipse on Saturday, causing the sun to resemble a sickle or a crescent. We’ll see a total lunar eclipse stateside the night of May 15-16.
 

Tecumsehsbones

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Two planets will appear to 'nearly collide' in the night sky this week
Author of the article:Washington Post
Washington Post
Matthew Cappucci, The Washington Post
Publishing date:Apr 26, 2022 • 17 hours ago • 4 minute read • Join the conversation

Early risers on Saturday will be treated to a planetary “conjunction” in the morning skies. NASA says the intermingling of Jupiter and Venus, which will only last two days, will make the planets appear to “almost collide.” The two celestial bodies are among the brightest objects currently present in the night sky.


While those with telescopes should easily be able to distinguish the two planets, there’s a chance that some naked-eye observers may witness a combined radiant overlap between the two.

The conjunction will be ongoing early on the morning of May 1, but, as the planets head their separate directions in the night sky, the duo will have swapped positions.

In addition to Venus and Jupiter, a trio of other planets will grace the skies, though they’ll probably only be visible for city skywatchers and stargazers with a telescope. In more rural areas, two of the other planets – Mars and Saturn – have already traced a perfect line as the solar system remains splayed out in a glorious splendor. They’ll continue to do so in the days ahead.


– – –

A “conjunction” occurs when two planets appear, from the vantage point of Earth, to swipe by one another in the sky. While there’s no specific metric that states how proximate they must be, the commonly accepted definition is within a couple of degrees. Conjunctions of Venus and Jupiter, the two most luminous planets in our skies, are known as “great conjunctions.”

On Dec. 21, 2020, the most spectacular great conjunction in 800 years brought Saturn and Jupiter just a tenth of a degree apart. For comparison, if you held your hand at arm’s length and closed one eye, the apparent width of your pinkie finger would be about a degree. Imagine a sliver of that. That’s about how close Jupiter came to nicking Saturn in 2020. It was the closest they’d been together since March 5, 1226, and the best great conjunction until 2080.


Technically speaking, there’s nothing to say one planet or celestial body can’t pass in front of another. It happens all the time with the Earth, sun and moon. When the moon fully obscures the sun and blocks sunlight from reaching Earth, it’s a total solar eclipse. Eclipses occur when objects are roughly the same apparent size in the sky.

Otherwise, a body that appears smaller may cross the face of a much larger-appearing body, resembling a small speck that intercedes as a blemish on whatever it’s blocking. That’s called a transit. Venus periodically transits in front of the sun, doing so every 243 years. Mercury’s transits are a bit more frequent, the last occurring on Nov. 11, 2019, with the next slated for Nov. 13, 2032. Those are the only two planets that let us witness a solar transit, since they have closer orbits to the sun than we Earthdwellers do.


Saturday morning’s show between Venus and Jupiter won’t be a “great” conjunction by the books, but it still will be “great” by virtue of being both scientifically captivating and visually stimulating.

Venus will appear brighter and on the lower right of the tangoing planets, while Jupiter sidesteps just a bit above and to the left.

– – –

Your best bet for enjoying the transit will be to look east before sunrise on Saturday, April 30. The predawn and twilight hours will be the best time to do so. That’s because Venus is the second-closest planet to the sun, so usually seeing it requires the sun to be relatively near in the sky – which is the case only at sunrise or sunset.

Venus is going to be about 92.9 million miles away from Earth on Saturday morning, or roughly the same distance as the sun. That may sound like a lot, but consider Jupiter. It’ll be 526.6 million miles away. Even though the two are more than 430,000,000 miles distant, they’ll appear close by just because of where they happen to be in their orbits.


You’ll be table to tell which one is Venus because it will be brighter and yellowish. That’s thanks to the thick sulfuric acid clouds that shroud its atmosphere, trapping heat and allowing the atmosphere to reach a scorching 900 plus degrees. (The atmosphere of Venus is also 90 times heavier than that of Earth, meaning that a person on the surface would be burned to death, crushed to death and poisoned to death all at once. Tourism to Venus is currently not recommended under current guidelines.)

Jupiter, on the other hand, may seem to have a reddish tinge to the naked eye. The gas giant spins every 10 hours, meaning every Earth day holds about 2.4 Jupiter days, but a “year” on Jupiter is actually 12 years long since it takes so long to orbit the sun.


On Sunday morning, Venus and Jupiter will still be flirting in proximity, but they’ll head their separate ways – Jupiter will rush up and right while Venus lays low to the horizon.

Both weekend days will also permit the viewing of Mars and Saturn under ideal conditions, but they’ll be much fainter and tougher to spot. Just trace a line up and right from Venus and Jupiter and you may run into them. If your skies are dark enough, it could make for a pretty special photo op.

As if that wasn’t enough, parts of South America will enjoy a partial solar eclipse on Saturday, causing the sun to resemble a sickle or a crescent. We’ll see a total lunar eclipse stateside the night of May 15-16.
1651078312832.png
 
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B00Mer

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www.getafteritmedia.com
Two planets will appear to 'nearly collide' in the night sky this week
Author of the article:Washington Post
Washington Post
Matthew Cappucci, The Washington Post
Publishing date:Apr 26, 2022 • 17 hours ago • 4 minute read • Join the conversation

Early risers on Saturday will be treated to a planetary “conjunction” in the morning skies. NASA says the intermingling of Jupiter and Venus, which will only last two days, will make the planets appear to “almost collide.” The two celestial bodies are among the brightest objects currently present in the night sky.


While those with telescopes should easily be able to distinguish the two planets, there’s a chance that some naked-eye observers may witness a combined radiant overlap between the two.

The conjunction will be ongoing early on the morning of May 1, but, as the planets head their separate directions in the night sky, the duo will have swapped positions.

In addition to Venus and Jupiter, a trio of other planets will grace the skies, though they’ll probably only be visible for city skywatchers and stargazers with a telescope. In more rural areas, two of the other planets – Mars and Saturn – have already traced a perfect line as the solar system remains splayed out in a glorious splendor. They’ll continue to do so in the days ahead.


– – –

A “conjunction” occurs when two planets appear, from the vantage point of Earth, to swipe by one another in the sky. While there’s no specific metric that states how proximate they must be, the commonly accepted definition is within a couple of degrees. Conjunctions of Venus and Jupiter, the two most luminous planets in our skies, are known as “great conjunctions.”

On Dec. 21, 2020, the most spectacular great conjunction in 800 years brought Saturn and Jupiter just a tenth of a degree apart. For comparison, if you held your hand at arm’s length and closed one eye, the apparent width of your pinkie finger would be about a degree. Imagine a sliver of that. That’s about how close Jupiter came to nicking Saturn in 2020. It was the closest they’d been together since March 5, 1226, and the best great conjunction until 2080.


Technically speaking, there’s nothing to say one planet or celestial body can’t pass in front of another. It happens all the time with the Earth, sun and moon. When the moon fully obscures the sun and blocks sunlight from reaching Earth, it’s a total solar eclipse. Eclipses occur when objects are roughly the same apparent size in the sky.

Otherwise, a body that appears smaller may cross the face of a much larger-appearing body, resembling a small speck that intercedes as a blemish on whatever it’s blocking. That’s called a transit. Venus periodically transits in front of the sun, doing so every 243 years. Mercury’s transits are a bit more frequent, the last occurring on Nov. 11, 2019, with the next slated for Nov. 13, 2032. Those are the only two planets that let us witness a solar transit, since they have closer orbits to the sun than we Earthdwellers do.


Saturday morning’s show between Venus and Jupiter won’t be a “great” conjunction by the books, but it still will be “great” by virtue of being both scientifically captivating and visually stimulating.

Venus will appear brighter and on the lower right of the tangoing planets, while Jupiter sidesteps just a bit above and to the left.

– – –

Your best bet for enjoying the transit will be to look east before sunrise on Saturday, April 30. The predawn and twilight hours will be the best time to do so. That’s because Venus is the second-closest planet to the sun, so usually seeing it requires the sun to be relatively near in the sky – which is the case only at sunrise or sunset.

Venus is going to be about 92.9 million miles away from Earth on Saturday morning, or roughly the same distance as the sun. That may sound like a lot, but consider Jupiter. It’ll be 526.6 million miles away. Even though the two are more than 430,000,000 miles distant, they’ll appear close by just because of where they happen to be in their orbits.


You’ll be table to tell which one is Venus because it will be brighter and yellowish. That’s thanks to the thick sulfuric acid clouds that shroud its atmosphere, trapping heat and allowing the atmosphere to reach a scorching 900 plus degrees. (The atmosphere of Venus is also 90 times heavier than that of Earth, meaning that a person on the surface would be burned to death, crushed to death and poisoned to death all at once. Tourism to Venus is currently not recommended under current guidelines.)

Jupiter, on the other hand, may seem to have a reddish tinge to the naked eye. The gas giant spins every 10 hours, meaning every Earth day holds about 2.4 Jupiter days, but a “year” on Jupiter is actually 12 years long since it takes so long to orbit the sun.


On Sunday morning, Venus and Jupiter will still be flirting in proximity, but they’ll head their separate ways – Jupiter will rush up and right while Venus lays low to the horizon.

Both weekend days will also permit the viewing of Mars and Saturn under ideal conditions, but they’ll be much fainter and tougher to spot. Just trace a line up and right from Venus and Jupiter and you may run into them. If your skies are dark enough, it could make for a pretty special photo op.

As if that wasn’t enough, parts of South America will enjoy a partial solar eclipse on Saturday, causing the sun to resemble a sickle or a crescent. We’ll see a total lunar eclipse stateside the night of May 15-16.

You are aware that the Andromeda Gallaxy and the Milky Way Gallaxy are racing towards each other at 402,000 kilometres per hour.

Yes, we are part of the Milky Way.. and when we collide it will be a show to remember..


 

spaminator

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Oct 26, 2009
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You are aware that the Andromeda Gallaxy and the Milky Way Gallaxy are racing towards each other at 402,000 kilometres per hour.

Yes, we are part of the Milky Way.. and when we collide it will be a show to remember..


1651196999211.png
 
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