Space News/UFO's Etc...(Discussion/Pics/Vids)
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It is amazing. He has taken over the role that was once our country's, when we were a bit more intelligent and ambitious.
Hubble finds relic galaxy close to home
By Eleanor Imster in SPACE | March 15, 2018
By Eleanor Imster in SPACE | March 15, 2018
Astronomers using NASA’s Hubble Space Telescope are investigating an ancient galaxy – called NGC 1277 – that’s in our cosmic backyard, 240 million light-years from Earth. What makes NGC 1277 unique is that the galaxy is composed exclusively of aging stars that were born 10 billion years ago. NGC 1277 started its life churning out stars 1,000 times faster than in our own Milky Way, but, unlike other galaxies in the local universe, NGC 1277 has not undergone any further star formation. The very rare and odd assemblage of stars has remained essentially unchanged for the past 10 billion years.
Astronomers nickname such galaxies as “red and dead,” because the stars are aging and there aren’t any successive generations of younger stars. Though Hubble has seen such “red and dead” galaxies in the early universe, one has never been conclusively found nearby. The findings were published in the March 12, 2018, issue of the peer-reviewed science journal Nature.
The researchers learned that although NGC 1277 has twice as many stars as our Milky Way, it’s one quarter of our galaxy in size. Essentially, the relic galaxy is in a state of “arrested development.” Perhaps, the researchers said, like all galaxies, it started out as a compact object but failed to accrete more material to grow in size to form a pinwheel-shaped galaxy.
Approximately one in 1,000 massive galaxies is expected to be a relic (or oddball) galaxy, like NGC 1277, researchers said. NGC 1277 offers a unique opportunity to see one up close and personal. Ignacio Trujillo, of the Instituto de Astrofisica de Canarias at the University of La Laguna, Spain, is an author of the study.
He said in statement: We can explore such original galaxies in full detail and probe the conditions of the early universe.
Stunning Mars images, from Curiosity
By Paul Scott Anderson in SPACE | TODAY'S IMAGE | March 16, 2018
By Paul Scott Anderson in SPACE | TODAY'S IMAGE | March 16, 2018
The Curiosity rover has sent back some beautiful new images of the foothills of Mount Sharp in Gale Crater on Mars. The first image is a panorama of the breathtaking view, thanks to processing by Thomas Appéré, who is an Associate Scientist at IPAG (l’Institut de Planétologie et d’ Astrophysique de Grenoble) in Grenoble, France. The rover is still making its way closer to these foothills at the base of the much taller mountain. The mesas and canyons are very reminiscent of the scenery in the American Southwest.
Curiosity has confirmed that Gale Crater used to contain a lake or series of lakes a few billion years ago, and fast-moving streams once emptied into the lake through the crater rim. Whether any life existed is still unknown, but this region was once a lot more habitable than it is today.
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Moon, Mercury, Venus March 18 to 20
By Bruce McClure in TONIGHT | March 18, 2018
By Bruce McClure in TONIGHT | March 18, 2018
Watch for the returning young moon, and the planets Mercury and Venus, beginning on the evening of March 18, 2018. The planets will still be there – and the moon will become much easier to see – on the nights of March 19 and 20.
On March 18, if you’re far enough west with respect to the International Date Line, and especially if you’re in the Northern Hemisphere, you’ve got a good shot at seeing a whisker-thin very young moon. The moon will be only one day past new moon on March 18, and thus the moon will be a very fragile crescent indeed, very lovely, setting soon behind the sun.
Sometimes, you can’t catch a young moon for a couple evenings after new moon. And sometimes you can’t see planets so near the sunset. But – around the spring equinox – you can. That’s because the ecliptic (path of the sun, moon and planets) stands nearly straight up with respect to the western horizon after sunset in spring. The spring angle of the ecliptic places the moon and planets at their highest above your horizon, after sunset.
Mercury: The Swift Planet
This colorful version of Mercury was assembled from spectral data taken with the MESSENGER spacecraft, highlighting various minerals on the planet's surface.
Mercury rotates on its axis with nearly no tilt whatsoever, meaning the planet experiences no seasons and there are places at the poles where sunlight never touches, blocked by steep crater walls. Solar radiation and micrometeorite impacts are two of the major forces that have shaped — and continue to influence — this world, and we are still digging for clues on its history and evolution. Only two spacecraft have ever visited, and the entire surface wasn't even imaged until earlier this century.
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Remember, Mercury is still visible tonight, next to Venus. See image a few posts above. Mercury was dubbed the Swift Planet by the Romans because it moves so quickly across the sky. It only takes 59 days for Mercury to revolve around the sun while it takes us 365 days, defining our year. - ilan
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thats awesomeMercury: The Swift Planet
This colorful version of Mercury was assembled from spectral data taken with the MESSENGER spacecraft, highlighting various minerals on the planet's surface.
Mercury rotates on its axis with nearly no tilt whatsoever, meaning the planet experiences no seasons and there are places at the poles where sunlight never touches, blocked by steep crater walls. Solar radiation and micrometeorite impacts are two of the major forces that have shaped — and continue to influence — this world, and we are still digging for clues on its history and evolution. Only two spacecraft have ever visited, and the entire surface wasn't even imaged until earlier this century.
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Remember, Mercury is still visible tonight, next to Venus. See image a few posts above. Mercury was dubbed the Swift Planet by the Romans because it moves so quickly across the sky. It only takes 59 days for Mercury to revolve around the sun while it takes us 365 days, defining our year. - ilan
Velikovsky’s Venus
Kelly Beatty in Sky & Telescope | March 20, 2018
Venus mimics all the phases of the Moon as it circles the Sun inside Earth’s orbit, as shown in this near-ultraviolet sequence recorded in 2007.Sean Walker
Kelly Beatty in Sky & Telescope | March 20, 2018
Venus mimics all the phases of the Moon as it circles the Sun inside Earth’s orbit, as shown in this near-ultraviolet sequence recorded in 2007.Sean Walker
A controversial 1950 book declared that our neighbor world was spawned by Jupiter 3,500 years ago and nearly struck Earth — twice.
As northern winter gives way to the longer daylight hours of spring, Venus returns to the evening sky for a long engagement. As the chart below shows, the planet doesn’t get as dramatically high in the sky as it did back in 2015. But the Evening Star will remain in view through September.
Telescopically, Venus never offers much to see aside from its gradual change in apparent size and an attractive progression of phases. Observers have strained for centuries to glimpse any detail on its cloud-cloaked disk. We sometimes forget that astronomers knew very little about this neighbor world — so like Earth in size and mass — until powerful radar probing and spacecraft visits started to peel back the layers of mystery in the 1960s.
The first artificial satellites were still a decade away when, in 1946, Immanuel Velikovsky finished the manuscript for Worlds in Collision, a book that capitalized on our relative ignorance and put forward a theory of solar-system formation that goes beyond bizarre. Born in 1895 and a student variously of history, law, biology, and psychoanalysis, Velikovsky maintained that the inner planets only recently assumed the serene, stable orbits they have today.
Rather, in his scheme Venus took the form of a huge, rogue comet after being ejected by Jupiter not long before 1500 BC. It then hurtled sunward, sideswiping Earth twice and colliding with Mars before settling into the almost perfectly circular orbit it now occupies.
The basis for all this astounding, historically recent chaos wasn’t a detailed computation of orbital motion but rather Velikovsky’s unwavering belief that Old Testament narratives and cosmological myths drawn from China, Central America, India, Assyria, and elsewhere were accounts of real events.
What got him started was the biblical story of Joshua commanding the Sun and Moon to stop moving for an entire day and invoking a devastating hail of stones from the sky during his battle with the Amorites. Velikovsky was also seeking a physical reason for the plagues inflicted on the Egyptians in Exodus.
Venus provided all the answers. That long tail it trailed after leaving Jupiter had also created all kinds of havoc for Pharaoh as Earth passed through it not once but twice. And although we escaped an outright collision, the proximity of Venus caused Earth’s orbit and axial tilt to change, a magnetic reversal, and worldwide floods, hurricanes, and volcanic eruptions — all within recorded history. None of this catastrophism was chronicled by our ancestors, Velikovsky asserts, because they suffered from a “collective amnesia” that repressed all memory of these occurrences. As further proof, he details how Venus is conspicuously absent from various historical tabulations of planets prior to about 2000 BC.
Velikovsky acknowledged that his scenario was at odds with established physics. But any inconsistencies weren’t due to his myth-as-fact interpretations; instead, he pointed to the “need for a new approach to celestial mechanics” in which electrical forces and magnetism trumped the power of gravity.
Understandably, astronomers of the day were outraged by all of this. It took Velikovsky four years to get Worlds in Collision published, finally getting a green light from Macmillan in part because a sympathetic Gordon Atwater, then head of astronomy at New York’s American Museum of Natural History, promised to create a show for Hayden Planetarium to depict the book’s planetary pinball. But Atwater was summarily fired before that could happen. Strenuous objections by Harvard’s Harlow Shapley, Cecelia Payne-Gaposchkin, and other academics — including a boycott of Macmillan’s astronomy textbooks — caused the publisher to jettison this literary hot potato to Doubleday. The book and its author merited a blistering editorial in Sky & Telescope.
A Curious, Believing Public
Remarkably, Worlds in Collision became phenomenally popular in the summer of 1950, especially among the New York literati. Advance articles about the forthcoming book in Harper’s, Collier’s, Reader’s Digest, and elsewhere whetted the public’s appetite. Once in print, the book rocketed to the top of the New York Times’ best-seller list and remained a top-ten pick for five months.
Although pilloried almost universally by professional astronomers, Velikovsky remained a frequent acquaintance of Albert Einstein. More than a decade later he gained a modicum of support thanks to Princeton physicist Valentine Bargmann and Columbia astronomer Lloyd Motz, whose letter in Science (December 21, 1962) pointed out Velikovsky’s successful predictions that Jupiter was a source of radio energy and that Venus must be very hot.
Still, one has to wonder why the outlandish premises of Worlds in Collision got so much traction in the first place. Science historian Stephen Jay Gould wrote, “The Velikovsky affair raises what is perhaps the most disturbing question about the public impact of science. How is a layman to judge rival claims of supposed experts? Any person with a gift for words can spin a persuasive argument about any subject not in the domain of a reader’s personal expertise.” Advocate-turned-critic Leroy Ellenberger notes, more pointedly, “The less one knows about science, the more plausible Velikovsky’s scenario appears.”
Six decades later, Worlds in Collision is rapidly disappearing in the rear-view mirror of history, yet our human penchant for intriguing but outlandish scientific claims remains.
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Remember what our departed friend Stephen Hawking had to say about alien visitors. His admonition begins in the third paragraph. - ilan
Physicist Stephen Hawking died at his home in Cambridge, England, on Wednesday.
Hawking’s earliest astrophysics work posited the existence of singularities, mathematically conforming black holes with Albert Einstein’s general theory of relativity. Hawking established, along with Roger Penrose, the universe’s origin as a singularity, i.e., a point in spacetime where traditional physical laws break down and gravity becomes infinite. His later work in quantum mechanics, inspired by collaboration with Soviet scientists Yakov Zel’dovich and Alexei Starobinsky, would mathematically indicate the finite entropy and evaporation of black holes as they emitted particles that came to be known as Hawking radiation. Though widely accepted as a breakthrough in theoretical physics, Hawking radiation and its resulting micro black holes have yet to be observed in experiments at CERN’s Large Hadron Collider.
His work in theoretical astrophysics (and the 1988 publication of his bestselling book A Brief History of Time) made Hawking a celebrity—including appearances on Star Trek: The Next Generation, The Simpsons and Futurama—which allowed Hawking a prominent public platform for his beliefs outside of physics. An atheist, anti-war activist, BDS supporter and anti-capitalist, the overlap between Hawking’s humanist politics and scientific interests found expression in his repeated public statements on the possibility of contact with extraterrestrial life.
Hawking took a conflicted position on alien life, at once promoting the search for extraterrestrial life and warning about the potential dangers of first contact with an alien species. His position on extraterrestrial life advocates two approaches: collecting intel and keeping as quiet as possible.
“There is no bigger question,” Hawking said, while announcing his support for Breakthrough Listen, a $100 million program to search for alien communications via radio wave and visible light observations of 1 million nearby stars and 100 galactic centers. “It is time to commit to finding the answer, to search for life beyond Earth.”
In 2010, Hawking worried what that answer would bring, describing the dangers of first contact with aliens in a Discovery Channel documentary. “If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans,” Hawking says. “We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet.”
“Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach,” Hawking said in the documentary, Into the Universe with Stephen Hawking.
Absent knowledge about alien life, Hawking urged documentary viewers to analogize their likely behavior to ours. Hawking noted that first encounters throughout our own history rarely begin with: “I’ll pop the kettle on. Milk? Sugar?”
He would reiterate this theme in a later documentary. “One day, we might receive a signal from a planet like this," he says in Stephen Hawking’s Favorite Places of the newly discovered world of Gliese 832c. “But we should be wary of answering back.”
During the announcement for Breakthrough Listen, Hawking said: “We don’t know much about aliens, but we know about humans. If you look at history, contact between humans and less intelligent organisms have often been disastrous from their point of view, and encounters between civilizations with advanced versus primitive technologies have gone badly for the less advanced. A civilization reading one of our messages could be billions of years ahead of us. If so, they will be vastly more powerful, and may not see us as any more valuable than we see bacteria.”
While Hawking expresses near certainty that alien life exists in the universe, he does not believe aliens have visited Earth in UFOs or at any point in history. “Why hasn’t the Earth been visited, and even colonised?” Hawking wrote on his official website. “I discount suggestions that UFOs contain beings from outer space. I think any visits by aliens, would be much more obvious, and probably also, much more unpleasant.”
In the essay Hawking describes some of the possibilities for the universe’s seeming silence, speculating that intelligence may be one of many possible evolutionary outcomes or, mostly darkly of all, the possibility that “intelligent life destroys itself.”
“I very much hope it isn’t true,” Hawking wrote.
STEPHEN HAWKING ON ALIEN LIFE, EXTRATERRESTRIALS AND THE POSSIBILITY OF UFOS VISITING EARTH
Andrew Whalen in Newsweek | 3/14/18 AT 12:31 PM
Andrew Whalen in Newsweek | 3/14/18 AT 12:31 PM
Physicist Stephen Hawking died at his home in Cambridge, England, on Wednesday.
Hawking’s earliest astrophysics work posited the existence of singularities, mathematically conforming black holes with Albert Einstein’s general theory of relativity. Hawking established, along with Roger Penrose, the universe’s origin as a singularity, i.e., a point in spacetime where traditional physical laws break down and gravity becomes infinite. His later work in quantum mechanics, inspired by collaboration with Soviet scientists Yakov Zel’dovich and Alexei Starobinsky, would mathematically indicate the finite entropy and evaporation of black holes as they emitted particles that came to be known as Hawking radiation. Though widely accepted as a breakthrough in theoretical physics, Hawking radiation and its resulting micro black holes have yet to be observed in experiments at CERN’s Large Hadron Collider.
His work in theoretical astrophysics (and the 1988 publication of his bestselling book A Brief History of Time) made Hawking a celebrity—including appearances on Star Trek: The Next Generation, The Simpsons and Futurama—which allowed Hawking a prominent public platform for his beliefs outside of physics. An atheist, anti-war activist, BDS supporter and anti-capitalist, the overlap between Hawking’s humanist politics and scientific interests found expression in his repeated public statements on the possibility of contact with extraterrestrial life.
Hawking took a conflicted position on alien life, at once promoting the search for extraterrestrial life and warning about the potential dangers of first contact with an alien species. His position on extraterrestrial life advocates two approaches: collecting intel and keeping as quiet as possible.
“There is no bigger question,” Hawking said, while announcing his support for Breakthrough Listen, a $100 million program to search for alien communications via radio wave and visible light observations of 1 million nearby stars and 100 galactic centers. “It is time to commit to finding the answer, to search for life beyond Earth.”
In 2010, Hawking worried what that answer would bring, describing the dangers of first contact with aliens in a Discovery Channel documentary. “If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans,” Hawking says. “We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet.”
“Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach,” Hawking said in the documentary, Into the Universe with Stephen Hawking.
Absent knowledge about alien life, Hawking urged documentary viewers to analogize their likely behavior to ours. Hawking noted that first encounters throughout our own history rarely begin with: “I’ll pop the kettle on. Milk? Sugar?”
He would reiterate this theme in a later documentary. “One day, we might receive a signal from a planet like this," he says in Stephen Hawking’s Favorite Places of the newly discovered world of Gliese 832c. “But we should be wary of answering back.”
During the announcement for Breakthrough Listen, Hawking said: “We don’t know much about aliens, but we know about humans. If you look at history, contact between humans and less intelligent organisms have often been disastrous from their point of view, and encounters between civilizations with advanced versus primitive technologies have gone badly for the less advanced. A civilization reading one of our messages could be billions of years ahead of us. If so, they will be vastly more powerful, and may not see us as any more valuable than we see bacteria.”
While Hawking expresses near certainty that alien life exists in the universe, he does not believe aliens have visited Earth in UFOs or at any point in history. “Why hasn’t the Earth been visited, and even colonised?” Hawking wrote on his official website. “I discount suggestions that UFOs contain beings from outer space. I think any visits by aliens, would be much more obvious, and probably also, much more unpleasant.”
In the essay Hawking describes some of the possibilities for the universe’s seeming silence, speculating that intelligence may be one of many possible evolutionary outcomes or, mostly darkly of all, the possibility that “intelligent life destroys itself.”
“I very much hope it isn’t true,” Hawking wrote.
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Only 117 years 'til this asteroid (possibly) hits us
Don Lincoln, CNN | Updated 6:07 PM ET, Thu March 22, 2018
Don Lincoln, CNN | Updated 6:07 PM ET, Thu March 22, 2018
(CNN) Chicken Little was right. In a very literal sense, the sky is falling. Not today and not tomorrow, but eventually. NASA has announced that on September 22, 2135 (which happens to be a Thursday, if you need to check your schedule), there is a small chance an asteroid a third of a mile across (named Bennu) will slam into the Earth with an impact energy equivalent to the currently deployed arsenal of US nuclear ballistic missiles.
Needless to say, if that happens, it will definitely be a bad day for everyone.
But, not to worry, NASA has a plan. In a theoretical exercise, a team of engineers devised a conceptual design of the Hypervelocity Asteroid Mitigation Mission for Emergency Response vehicle, or HAMMER. It is a hypothetical spacecraft that could either ram into Bennu or target it with a nuclear device, either of which it is hoped would deflect the asteroid away from Earth.
HAMMER is not an actual NASA program, but rather an investigation into the technical challenges that would arise in building such a device. The 1998 movies "Armageddon" and "Deep Impact" were dramatizations of broadly similar efforts.
While it is rather unlikely that Bennu will actually hit Earth, it is inevitable that eventually a similar one will. The probability of an impact is high for smaller rocks and decreases rapidly for larger asteroids.
In 2013, a meteor about 60 feet (20 meters) across hit the Earth near Chelyabinsk in Russia. This relatively small rock still did considerable damage. It released about 30 times as much energy as the nuclear explosion at Hiroshima, blowing out glass windows and causing 1,500 people to seek medical attention.
It was small enough that the energy was mostly dissipated in the atmosphere, although a few rocks hit Earth. At the other end of the spectrum was a meteor about 10 miles (16 kilometers) in diameter that hit the Yucatan Peninsula 65 million years ago with enough energy to wipe out the dinosaurs as a dominant form of life on Earth. This meteor left a crater about 100 miles (150 kilometers) across.
Meteors like the Chelyabinsk one are fairly common, hitting the Earth every few years, while those on the scale of the Yucatan one happen perhaps every 100 million years or so. In between are impacts comparable to the Bennu asteroid, which are also fairly rare, perhaps once every 100,000 years.
But even smaller meteors can cause considerable damage. And they are surprisingly common, although luckily most impacts occur over the oceans or uninhabited regions around the globe. An impact of even a modest-sized meteor could have catastrophic consequences if it were to occur over a large city. Humanity would have to intervene to avoid massive loss of life. Ideally, that intervention would be a mission like HAMMER to avoid the collision entirely.
In the asteroid-deflection business, warning is everything. A small amount of force applied to an asteroid many years before a predicted impact can easily alter the asteroid's orbit, while a last minute intervention could require so much force that it might well be impossible to avoid the impact.
With that in mind, NASA set up a program whose chief executive has what could well be the coolest title of any position in any organization: Planetary Defense Officer. The Planetary Defense Coordination Office oversees studies of mitigation efforts (like HAMMER and others) but also the near Earth orbit, or NEO, observations program. The Center for NEO Studies is dedicated to watching the skies, looking for large space rocks in orbits that could intersect the Earth.
CNEOS has discovered approximately 18,000 near-Earth objects, with nearly 1,000 of them being over a kilometer in size. Those, of course, are the most dangerous ones. The NEO search program has existed in various forms since the 1970s.
In 1998, NASA was directed by the Congressional Committee on Science, Space and Technology to look for possible threats of asteroids larger than a kilometer. The program has become more sophisticated over the last two decades.
There are a bunch of NEOs out there and astronomers have found perhaps 90% of those larger than a kilometer and a lesser fraction of smaller ones. Of all NEOs found, NASA's programs were responsible for 98% of the discoveries, with other astronomers finding the others. At a very modest fraction of NASA's overall budget, this office is the sentinel, watching and waiting, warning us of potentially serious dangers. This is an important effort and one well worth our support.
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Jupiter’s Red Spot gets taller as it shrinks
Eleanor Imster in SPACE | March 21, 2018
Jupiter’s Great Red Spot is a giant oval of crimson-colored clouds in Jupiter’s southern hemisphere. The clouds race counterclockwise around the oval’s perimeter with wind speeds greater than any storm on Earth. Measuring 10,000 miles (16,000 km) in width as of April 2017, the Great Red Spot is 1.3 times as wide as Earth. This looping animation simulates the motion of clouds in the Great Red Spot. Image via NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt/Justin Cowart.
Amy Simon is an expert in planetary atmospheres at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the new paper. She said in a statement:Eleanor Imster in SPACE | March 21, 2018
Jupiter’s Great Red Spot is a giant oval of crimson-colored clouds in Jupiter’s southern hemisphere. The clouds race counterclockwise around the oval’s perimeter with wind speeds greater than any storm on Earth. Measuring 10,000 miles (16,000 km) in width as of April 2017, the Great Red Spot is 1.3 times as wide as Earth. This looping animation simulates the motion of clouds in the Great Red Spot. Image via NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstadt/Justin Cowart.
Storms are dynamic, and that’s what we see with the Great Red Spot. It’s constantly changing in size and shape, and its winds shift, as well.
The study confirms that the storm has been decreasing in length overall since 1878 and is big enough to accommodate just over one Earth at this point. But the historical record indicates the area of the spot grew temporarily in the 1920s. Reta Beebe, an emeritus professor at New Mexico State University in Las Cruces, is a study co-author. Beebe said:
There is evidence in the archived observations that the Great Red Spot has grown and shrunk over time. However, the storm is quite small now, and it’s been a long time since it last grew.
Because the storm has been contracting, the researchers expected to find the already-powerful internal winds becoming even stronger, like an ice skater who spins faster as she pulls in her arms. But instead of spinning faster, the storm appears to be forced to stretch up, like clay being shaped on a potter’s wheel. As the wheel spins, an artist can transform a short, round lump into a tall, thin vase by pushing inward with his hands. The smaller he makes the base, the taller the vessel will grow. In the case of the Great Red Spot, the change in height is small relative to the area that the storm covers, but still noticeable, say the researchers.
The Great Red Spot’s color has been deepening, too, becoming intensely orange since 2014. Researchers aren’t sure why that’s happening, but say it’s possible that the chemicals which color the storm are being carried higher into the atmosphere as the spot stretches up. At higher altitudes, the chemicals would be subjected to more UV radiation and would take on a deeper color.
Observations of Jupiter date back centuries, but the first confirmed sighting of the Great Red Spot was in 1831. Since then, observers have been able to measure the size and drift of the Great Red Spot by fitting their telescopes with an eyepiece scored with crosshairs. A continuous record of at least one observation of this kind per year dates back to 1878.
For the current study, the researchers drew on this archive of historical observations and combined them with data from NASA spacecraft, starting with the two Voyager missions in 1979. In particular, the group relied on a series of annual observations of Jupiter that team members have been conducting with NASA’s Hubble Space Telescope as part of the Outer Planets Atmospheres Legacy, or OPAL, project.
The team traced the evolution of the Great Red Spot, analyzing its size, shape, color and drift rate. They also looked at the storm’s internal wind speeds, when that information was available from spacecraft.
Bottom line: A new study suggests Jupiter’s Great Red Spot is growing taller as it shrinks.
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Tiangong-1: Chinese space station predicted to crash somewhere on Earth around Easter
Genelle Weule, ABC Science | Updated 25 March 2018
Space experts predict the Tiangong-1 space station, or "Heavenly Palace", will turn into a spectacular fireball as it enters Earth's atmosphere sometime during the Easter long weekend.Genelle Weule, ABC Science | Updated 25 March 2018
According to the latest predictions, it will begin its fiery descent into Earth's atmosphere somewhere in a window between March 30 and April 3 — possibly around April 1.
But there are concerns the bus-sized spacecraft is out of control.
That means some debris from the fireball could hit the Earth anywhere in a band between 43 degrees north and south of the equator.
But you would have to be extremely unlucky to be taken out by a chunk of debris from Tiangong-1, according to space engineer Warwick Holmes, executive director of space engineering at the University of Sydney's School of Aerospace.
How do we know if it's out of control?
Not long after it was decommissioned, rumours began to circulate that the Chinese agency had lost control of the craft.
"It seems they lost communication link to the space station so there is no data link between Tiangong-1,"
Dr Wu said it had been planned to deorbit in September 2017, but this did not happen.
If there is no data link, ground engineers cannot fire up the engines to help control where the spacecraft lands.
"You can't activate or turn [the thruster engine] on so in this case you can't control the orbit," Dr Wu explained.
But, he added, the status of the craft was unknown.
Are some places more likely to get hit than others?
Tiangong-1 orbits Earth once every one-and-a-half hours in a rollercoaster orbit pinging between the latitudes of 43 degrees north and 43 degrees south.
That is as far north as Boston and as south as Hobart.
Hurtling at a speed of around seven kilometres a second (the equivalent of travelling between Sydney and Perth in about eight minutes), it is never anywhere long.
Originally it was intended the craft would burn into smithereens somewhere over a remote part of the south Pacific Ocean, between New Zealand and South America at the bottom of this band.
This location, known as the "spacecraft cemetery", is the final resting place of space junk from a multitude of large spacecraft sent up into the sky by the US, Russia, Europe and Japan.
But, if communication has been lost with the craft, the re-entry point is much less certain.
According to Aerospace and the European Space Agency, the areas at the edges of this band had a slightly higher risk.
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10 surprises about our solar system
Larry Sessions in SPACE | March 26, 2018
Larry Sessions in SPACE | March 26, 2018
Here are 10 unexpected and intriguing facts about our solar system – our sun and its family of planets – you probably did not know!
1. The hottest planet isn’t closest to the sun. Many people know that Mercury is the closest planet to the sun, well less than half of the Earth’s distance. It’s no mystery, therefore, why people would assume that Mercury is the hottest planet. We know that Venus, the second planet away from the sun, is on the average 30 million miles (48 million km) farther from the sun than Mercury. The natural assumption is that, being farther away, Venus must be cooler. But assumptions can be dangerous. For practical consideration, Mercury has no atmosphere, no warming blanket to help it maintain the sun’s heat. Venus, on the other hand, is shrouded by an unexpectedly thick atmosphere, about 100 times thicker than Earth’s atmosphere. This in itself would normally serve to prevent some of the sun’s energy from escaping back into space and thus raise the overall temperature of the planet. But in addition to the atmosphere’s thickness, it is composed almost entirely of carbon dioxide, a potent greenhouse gas. The carbon dioxide freely lets solar energy in, but is much less transparent to the longer wavelength radiation emitted by the heated surface. Thus the temperature rises to a level far above what would be expected, making it the hottest planet. In fact the average temperature on Venus is about 875 degrees Fahrenheit (468 degrees Celsius), hot enough to melt tin and lead. The maximum temperature on Mercury, the planet closer to the sun, is about 800 degrees F (427 degrees C). In addition, the lack of atmosphere causes Mercury’s surface temperature to vary by hundreds of degrees, whereas the thick mantle of carbon dioxide keeps the surface temperature of Venus steady, hardly varying at all, anywhere on the planet or any time of day or night!
New Horizons captured this image of Pluto on July 25, 2015, when the spacecraft was 280,000 miles (450,000 km) from the planet. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
2. Pluto is smaller than the U.S. The greatest distance across the contiguous United States – from Northern California to Maine – is nearly 2,900 miles (about 4,700 km). Thanks to the New Horizons spacecraft in 2015, we now know that Pluto is 1,473 miles (2,371 km) across, less than half the width of the U.S. Certainly in size it is much smaller than any major planet, perhaps making it a bit easier to understand why, in 2006, the International Astronomical Union changed Pluto’s status from major planet to dwarf planet.
3. George Lucas doesn’t know much about asteroid fields. In many science fiction movies, spacecraft are often endangered by pesky asteroid fields. In actuality, the only asteroid belt we are aware of exists between Mars and Jupiter, and although there are tens of thousands of asteroids in it (perhaps more), they are quite widely spaced and the likelihood of colliding with one is small. In fact, spacecraft must be deliberately and carefully guided to asteroids to have a chance of even photographing one. Given the presumed manner of asteroid creation, it is highly unlikely that spacefarers will ever encounter asteroid swarms or fields in deep space.
4. You can make volcanos using water as magma. Mention volcanoes and everyone immediately thinks of Mount St. Helens, Mount Vesuvius, or maybe the lava caldera of Mauna Loa in Hawaii. Volcanos require molten rock called lava (or magma when still underground), right? Not really. A volcano forms when an underground reservoir of a hot, fluid mineral or gas erupts onto the surface of a planet or other non-stellar astronomical body. The exact composition of the mineral can vary greatly. On Earth, most volcanoes sport lava (or magma) that has silicon, iron, magnesium, sodium, and a host of complicated minerals. The volcanoes of Jupiter’s moon Io appear to be composed mostly of sulfur and sulfur dioxide. But it can be simpler than that. On Saturn’s moon Enceladus, Neptune’s moon Triton, and others, the driving force is ice, good old frozen H20! Water expands when it freezes and enormous pressures can build up, just as in a “normal” volcano on Earth. When the ice erupts, a cryovolcano is formed. So volcanoes can operate on water as well as molten rock. By the way, we have relatively small scale eruptions of water on Earth called geysers. They are associated with superheated water that has come into contact with a hot reservoir of magma.
5. The edge of the solar system is 1,000 times farther away than Pluto. You might still think of the solar system as extending out to the orbit of the much-loved dwarf planet Pluto. Today we don’t even consider Pluto a full-fledged planet, but the impression remains. Still, we have discovered numerous objects orbiting the sun that are considerably farther than Pluto. These are Trans-Neptunian Objects (TNOs) or Kuiper Belt Objects (KBOs). The Kuiper Belt, the first of the sun’s two reservoirs of cometary material, is thought to extend to 50 or 60 astronomical units (AU, or the average distance of the Earth from the sun). An even farther part of the solar system, the huge but tenuous Oort comet cloud, may extend to 50,000 AU from the sun, or about half a light-year – more than 1,000 times farther than Pluto.
6. Almost everything on Earth is a rare element. The elemental composition of planet Earth is mostly iron, oxygen, silicon, magnesium, sulfur, nickel, calcium, sodium, and aluminum. While such elements have been detected in locations throughout the universe, they are merely trace elements, vastly overshadowed by the much greater abundances of hydrogen and helium. Thus Earth, for the most part, is composed of rare elements. This does not signify any special place for Earth, however. The cloud from which the Earth formed had a much higher abundance of hydrogen and helium, but being light gases, they were driven away into space by the sun’s heat as the Earth formed.
7. There are Mars rocks on Earth (and we didn’t bring them here). Chemical analysis of meteorites found in Antarctica, the Sahara Desert, and elsewhere have been shown by various means to have originated on Mars. For example, some contain pockets of gas that is chemically identical to the Martian atmosphere. These meteorites may have been blasted away from Mars due to a larger meteoroid or asteroid impact on Mars, or by a huge volcanic eruption, and later collided with Earth.
8. Jupiter has the biggest ocean of any planet, albeit made of metallic hydrogen. Orbiting in cold space five times farther from the sun than Earth, Jupiter retained much higher levels of hydrogen and helium when it formed than did our planet. In fact, Jupiter is mostly hydrogen and helium. Given the planet’s mass and chemical composition, physics demands that way down under the cold cloud tops, pressures rise to the point that the hydrogen must turn to liquid. In fact there should be a deep planetary ocean of liquid hydrogen. Computer models show that not only is this the largest ocean known in the solar system, but that it is about 25,000 miles (40,000 km) deep – roughly as deep as the Earth is around!
9. Even really small bodies can have moons. It was once thought that only objects as large as planets could have natural satellites or moons. In fact the existence of moons, or the capability of a planet to gravitationally control a moon in orbit, was sometimes used as part of the definition of what a planet truly is. It just didn’t seem reasonable that smaller celestial bodies had enough gravity to hold a moon. After all, Mercury and Venus have none at all, and Mars has only tiny moons. But in 1993, the Galileo probe passed the 20-mile wide asteroid Ida and discovered its one-mile wide moon, Dactyl. Since then moons have been discovered orbiting many other minor planets in our solar system.
10. We live inside the sun. Normally we think of the sun as being that big, hot ball of light 93 million miles (150 million km) away. But actually, the sun’s outer atmosphere extends far beyond its visible surface. Our planet orbits within this tenuous atmosphere, and we see evidence of this when gusts of the solar wind generate the Northern and Southern Lights. In that sense, we definitely live inside the sun. But the solar atmosphere doesn’t end at Earth. Auroras have been observed on Jupiter, Saturn, Uranus, and even distant Neptune. In fact, the outer solar atmosphere, called the heliosphere, is thought to extend at least 100 A.U. That’s nearly 10 billion miles (16 billion km). In fact the atmosphere is likely teardrop shaped due to the sun’s motion in space, with the “tail” extending tens to hundreds of billions of miles downwind.
This artist’s concept puts solar system distances in perspective. The scale bar is in astronomical units, with each set distance beyond 1 AU representing 10 times the previous distance. One AU is the distance from the sun to the Earth, which is about 93 million miles or 150 million kilometers. NASA’s Voyager 1, humankind’s most distant spacecraft, is around 125 AU. Image via NASA/JPL-Caltech.
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