Tag: space

These Weird Red Arcs On Saturn’s Moon Tethys Can’t Be Explained

An icy moon of Saturn has mysterious red arcs of material crisscrossing its surface — and no one knows exactly how they got there.

The Cassini spacecraft caught these graffiti-like features on camera as it imaged the northern side of the Tethys, which is one of Saturn’s larger moons.

While the arcs faintly show up in 2004 pictures, the latest images, from April, are the first to really show their colors by incorporating the right viewing conditions and wavelengths invisible to the human eye.

This is partly because Saturn and its moons’ northern hemispheres are currently in summer, providing better illumination of this region.

The features were a surprise to scientists because red tints are rare in the solar system.




Until now, astronomers have spotted a few small, reddish craters on Saturn’s icy moon Dione, and identified many rouge zones on the icy surface of Jupiter’s Europa.

Scientists don’t exactly know how these features occurred. Perhaps they are ice with chemical impurities, leftovers from gas released from the moon or artifacts from features that were smaller than the resolution of the image.

The red arcs must be geologically young, because they cut across older features like impact craters, but we don’t know their age in years.” Paul Helfenstein, a Cassini imaging scientist at Cornell University who helped plan the observations, said in a statement.

If the stain is only a thin, colored veneer on the icy soil, exposure to the space environment at Tethys’ surface might erase them on relatively short time scales.

Icy moons lke Tethys are considered a key area of interest in our solar system because they could host microbial life if enough chemical energy and warmth is available in the oceans below the ice.

In recent years, plumes of gas have been repeatedly observed at Enceladus, another of Saturn’s moons, and in 2013 the Hubble Space Telescope spotted a single, large-plume event at Europa.

Cassini will do follow-up observations of Tethys at a higher resolution later this year. The mission is in the final two years of work before the spacecraft runs low on fuel in September 2017.

When that happens, it will plunge into Saturn’s atmosphere to protect the icy moons from possible contamination.

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President Trump Directs NASA To Return To The Moon, Then Aim For Mars

President Donald Trump signed his administration’s first space policy directive today (Dec. 11), which formally directs NASA to focus on returning humans to the moon.

President Trump signed the order during a ceremony in the Oval Office, surrounded by members of the recently re-established National Space Council (NSC).

As well as active NASA astronauts Christina Hammock Koch and Peggy Whitson, Apollo 11 astronaut Buzz Aldrin, and retired astronaut Jack Schmitt, who flew to the moon on the Apollo 17 mission.

The directive I’m signing today will refocus America’s space program on human exploration and discovery,” Trump said during the ceremony.

It marks an important step in returning American astronauts to the moon for the first time since 1972, for long-term exploration and use.”




This time we will not only plant our flag and leave our footprint — we will establish a foundation for an eventual mission to Mars and perhaps someday to many worlds beyond.

Space Policy Directive 1 makes official a recommendation approved by the NSC in October. Vice President Mike Pence, who serves as chairman of the NSC, also spoke at the signing.

NASA recently announced that for human astronauts, the path to Mars will include a stop at the moon, where the agency may build a facility currently being called the Deep Space Gateway.

That structure could serve as a kind of way station between the Earth and the Red Planet.

Robert Lightfoot, NASA’s acting administrator, said he thinks the new directive could provide “a sense of urgency” to NASA’s spaceflight pursuits.

He noted that there are “a lot of people that want to help [NASA]” reach those goals, including international space partners and commercial space partners in the U.S.A.

In a separate statement, NASA officials said that the directive also officially ends NASA’s Asteroid Redirect Mission (ARM), which would have sent robotic probes and then humans to an asteroid.

The Space Policy Directive 1 will “more effectively organize government, private industry, and international efforts toward returning humans [to] the Moon, and will lay the foundation that will eventually enable human exploration of Mars,” agency officials said.

Both the president and the vice president said today that NASA’s focus on its human spaceflight program will help create jobs for the country, and both men briefly mentioned the defense and military applications of the space program.

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NASA Reveals That Our Solar System’s First Interstellar Visitor Is Shaped Like A Cigar

A newly discovered object from another star system that’s passing through ours is shaped like a giant cigar with a reddish hue, astronomers have revealed.

The asteroid, named ‘Oumuamua by its discoverers, is up to one-quarter mile (400 meters) long and highly-elongated – perhaps 10 times as long as it is wide.

That aspect ratio is greater than that of any asteroid or comet observed in our solar system to date.

While its elongated shape is quite surprising, and unlike asteroids seen in our solar system, it may provide new clues into how other solar systems formed.

The observations and analyses were funded in part by NASA and appear in the Nov. 20 issue of the journal Nature.




They suggest this unusual object had been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with our star system.

For decades we’ve theorized that such interstellar objects are out there, and now, for the first time, we have direct evidence they exist,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate in Washington.

“This history-making discovery is opening a new window to study formation of solar systems beyond our own.”

Combining the images from the FORS instrument on the ESO telescope using four different filters with those of other large telescopes.

A team of astronomers led by Karen Meech of the Institute for Astronomy in Hawaii found that ‘Oumuamua varies in brightness by a factor of ten as it spins on its axis every 7.3 hours.

No known asteroid or comet from our solar system varies so widely in brightness, with such a large ratio between length and width.

The most elongated objects we have seen to date are no more than three times longer than they are wide.

This unusually big variation in brightness means that the object is highly elongated: about ten times as long as it is wide, with a complex, convoluted shape,” said Meech.

These properties suggest that ‘Oumuamua is dense, comprised of rock and possibly metals, has no water or ice, and that its surface was reddened due to the effects of irradiation from cosmic rays over hundreds of millions of years.

Scientists are certain this asteroid or comet originated outside our solar system.

First spotted last month by the Pan-STARRS telescope in Hawaii, it will stick around for another few years before departing our sun’s neighborhood.

Jewitt and his international team observed the object for five nights in late October using the Nordic Optical Telescope in the Canary Islands and the Kitt Peak National Observatory near Tucson, Arizona.

At approximately 100 feet by 100 feet by 600 feet, the object has proportions roughly similar to a fire extinguisher — though not nearly as red, Jewitt said.

The slightly red hue specifically pale pink and varying brightness are remarkably similar to asteroids in our own solar system, he noted.

In a paper to the Astrophysical Journal Letters, the scientists report that our solar system could be packed with 10,000 such interstellar travelers at any given time.

It takes 10 years to cross our solar system, providing plenty of future viewing opportunities, the scientists said.

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It Was A Universe-Shaking Announcement. But What Is A Neutron Star Anyway?

Last October 16, 2017, astronomers made a universe-shaking announcement about the detection of reverberations from the collision of two neutron stars.

It is another triumph for LIGO, short for Laser Interferometer Gravitational-Wave Observatory, the instrument that has opened a new window into the universe by detecting shakings in the fabric of space-time known as gravitational waves.

Previously, LIGO, had detected three mergers of black holes. Scientists who helped create LIGO also just won the Nobel Prize in Physics.

The new discovery sheds light on a smaller, different type of rumbling, one that can be both seen and heard. Here are answers to some questions you might have about the discovery.




What’s a neutron star?

Let’s back up a step: what’s a neutron? An atom consists of a heavy center known as the nucleus, surrounded by a cloud of tiny negatively charged electrons.

In the nucleus are two types of particles: positively charged protons and electrically neutral neutrons.

A neutron star, as its name suggests, is a star that consists almost entirely of neutrons.

Here’s how that neutron star formed:

For most of their existence, stars emit light through fusion the merging of hydrogen atoms into helium, which releases gargantuan amounts of energy.

When a large star probably at least six times the mass of the sun exhausts its hydrogen, it begins to collapse.

The collapse accelerates so quickly that it sets off cataclysmic explosion known as a supernova. What’s left over is an extremely dense cinder that is only about six miles wide, but packs in more mass than the sun.

The pressure is so great that electrons and protons are squeezed together into neutrons.

A single thimbleful of a neutron star weighs as much as several million elephants.

How does a neutron star differ from a black hole?

A neutron star is a stellar cinder that stopped collapsing.

But when even larger stars explode, the remaining core is so dense that the core continues collapsing until it turns into a black hole. Here’s our guide to black holes.

What happens when two neutron stars collide?

In the case of the discovery that was detailed last October 16, 2017, the merging objects were probably survivors of massive stars that had been orbiting each other and had each puffed up and then died in spectacular supernova explosions.

Making reasonable assumptions about their spins, the astronomers calculated that these neutron stars were about 1.1 and 1.6 times as massive as the sun, smack in the known range of neutron stars.

As they approached each other, swirling a thousand times a second, tidal forces bulged their surfaces outward. Quite a bit of the material was ejected and formed a fat doughnut around the merging stars.

At the moment they touched each other, a shock wave squeezed more material out of their polar regions, but the doughnut and extreme magnetic fields confined the material into an ultra-high-speed jet emitting a blitzkrieg of radiation.

That blast set off the gravitational waves detected by LIGO, as well as the light show spotted by a variety of telescopes.

What are gravitational waves?

Watch this video we made in 2016 when LIGO first detected them to learn more about these ripples in space-time that confirmed key aspects of Albert Einstein’s theories.

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Mystery Of The Zombie Star That Won’t Die

A brightly burning ‘zombie‘ supernova that refuses to die has left astronomers baffled.

The star, which lies half a billion light years away, has exploded numerous times since 1954.

This has stumped astronomers as supernovas are generally considered to explode just once and standard theoretical models cannot explain its behaviour.

Researchers at Las Cumbres Observatory in Goleta, California, have been studying the phenomenon, which was first observed in 2014 by the Intermediate Palomar Transient Factory telescope near San Diego.

In January 2015 the event, known as iPTF14hls, was classified as a type II-P supernova, which results from the rapid collapse and violent explosion of a single massive star.




This type of supernova gives off a distinctive flash and tend to stay bright for around 100 days and supernovae lasting more than 130 days are extremely rare.

But iPTF14hls remained bright for almost two years (600 days), with the brightness of the light it emitted varying by up to 50 per cent over this time, as if it were exploding over and over again.

The evolution of the event also seems to be taking place roughly ten times slower than others of its type.

Adding to the puzzle, telescope imagery uncovered by the team suggests explosions may have taken place at the same location in 1954.

Supernovae are known to explode only once, shine for a few months and then fade, but iPTF14hls experienced at least two explosions, 60 years apart.

Writing in an opinion piece for the journal Nature, Stan Woosley, a professor of astronomy at the University of California, Santa Cruz, said of the findings.

As of now, no detailed model has been published that can explain the observed emission and constant temperature of iPTF14hls, let alone the possible eruption 60 years before the supernova.

“A better understanding could provide insight into the evolution of the most massive stars, the production of the brightest supernovae and possibly the birth of black holes that have masses near 40 solar masses, such as those associated with the first direct detection of gravitational waves.”

“For now, the supernova offers astronomers their greatest thrill: something they do not understand.”

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Oldest Monster Black Hole Ever Found Is 800 Million Times More Massive Than the Sun

Astronomers have discovered the oldest supermassive black hole ever found — a behemoth that grew to 800 million times the mass of the sun when the universe was just 5 percent of its current age, a new study finds.

This newfound giant black hole, which formed just 690 million years after the Big Bang, could one day help shed light on a number of cosmic mysteries.

Such as how black holes could have reached gargantuan sizes quickly after the Big Bang and how the universe got cleared of the murky fog that once filled the entire cosmos, the researchers said in the new study.




Supermassive black holes with masses millions to billions of times that of the sun are thought to lurk at the hearts of most, if not all, galaxies.

Previous research suggested these giants release extraordinarily large amounts of light when they rip apart stars and devour matter, and likely are the driving force behind quasars, which are among the brightest objects in the universe.

Astronomers can detect quasars from the farthest corners of the cosmos, making quasars among the most distant objects known.

The farthest quasars are also the earliest known quasars — the more distant one is, the more time its light took to reach Earth.

The previous record for the earliest, most distant quasar was set by ULAS J1120+0641. That quasar is located 13.04 billion light-years from Earth and existed about 750 million years after the Big Bang.

The newfound quasar (and its black hole), named ULAS J1342+0928, is 13.1 billion light-years away.

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Bacteria On Space Station Likely From Germy Humans, Not Aliens

Living bacteria have been found on the outside of the International Space Station, a Russian cosmonaut told the state news agency TASS this week.

Anton Shkaplerov, who will lead Russia’s ISS crew in December, said that previous cosmonauts swabbed the station’s Russian segment during spacewalks and sent the samples back to Earth.

The samples came from places on the station that had accumulated fuel waste, as well as other obscure nooks and crannies.

Their tests showed that the swabs held types of bacteria that were not on the module when it originally launched into orbit, Shkaplerov says.

In his interview with TASS, Shkaplerov says the bacteria “have come from outer space and settled along the external surface“, a claim that sparked some media outlets to issue frenzied reports about aliens colonizing the space station.

For now, though, details about the swabbing experiment are thin on the ground.




Shkaplerov did not note whether the study has been vetted by a peer-reviewed journal, which means it’s unclear exactly when and how the full experiment was conducted, or how the team avoided any contamination from much more mundane bacteria on the cosmonauts or in the Earth-bound lab.

Interview requests with the Russian space agency were unanswered when this article went to press. Up in the vacuum of space, microbes have to deal with turbulent temperatures, cosmic radiation, and ultraviolet light.

But Earth is home to plenty of hardy organisms that can survive in extreme environments, like virtually indestructible tardigrades.

Sometimes, researchers intentionally send terrestrial contaminants, such as E. coli and rocks covered in bacteria, into space to see how it will react.

And TASS reports that on a previous ISS mission, bacteria accidentally hitched a ride to the station on tablet PCs and other materials.

Scientists sent these objects up to see how they would fare in space, and the freeriding organisms managed to infiltrate the outside of the station.

They remained there for three years, braving temperatures fluctuating between -150 and 150 degrees Celsius.

 

These types of discoveries present concerns for scientists trying to limit the spread of human germs on other worlds.

NASA in particular has set strict limits on its interplanetary contamination.

Apollo astronauts were quarantined when they returned from their missions, for example, to prevent extraterrestrial germs from making their way out into the world.

And almost all equipment from Earth is sterilized before it heads skyward, either with extreme heat or an alcohol bath, depending on its intended destination.

These treatments are especially important for missions sent to Mars, which may have once hosted its own life-forms, leaving fossil traces in the rusty rocks.

But all bets may be off when and if we manage to send humans to explore Mars, writes The Planetary Society’s Emily Lakdawalla: “Once we’ve put humans on the surface, alive or dead, it becomes much, much harder to identify native Martian life.”

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The Big Bang Wasn’t The Beginning

What if the Big Bang wasn’t the beginning of the universe, but only one stage in an endlessly repeated cycle of universal expansion and contraction?

So suggests mathematical physicist and string theorist Neil Turok.

He thinks there may be many universes, at once interpolated but separate, like a mixture of gases.

These universes are attracted to each other; every few trillions of trillions of years, they collide, explode, expand and contract, then repeat the sequence all over again.

According to Turok, winner of the first TED Prize of 2008, “The Big Bang theory rests very strongly on Einstein’s theory of general relativity, which combines with nuclear and particle physics and all the other physical laws to describe the contents of the universe.




The theory is that 13.7 billion years ago, there was a singularity, a point of infinite density, and the universe emerged, emerging and very hot, from that singularity.

But the singularity is not describable with Einstein’s theory. The theory fails: everything goes to infinity. The density of the universe goes to infinity.

The curvature of spacetime goes to infinity. All the properties we normally use to describe the universe and its contents just fail.

Experts just say, “Let’s assume the universe sprang into existence, start our decription a tiny fraction of a second after that, run the clock forward and never ask where it came from.”

Turok’s theory:

“Imagine two sheets on a washing line, and they’re very close together, very nearly parallel. Those are two-dimensional sheets; ours are three-dimensional.”

“Think of it as two intimately intertwined objects which are nevertheless able to exert force on each other, a pull. The Big Bang is the touching of those two sheets. When they touch, they release that energy.”

Interestingly, Turok’s theory hasn’t always been well-received by Christians, for whom the Big Bang dovetails neatly with their creation myths.

Conversely, New Age types have embraced this scientific picture of a cyclical universe without beginning or end. Turok, for his part, doesn’t want any such attention.

I see religion and science as being two completely different things,” he said.

Science studies how the world operates, not why it?’s here. I think the world is an incredible miracle, and we have to do whatever we can to appreciate it.”

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Leftovers From The Moon’s Formation May Have Tunnelled To The Earth’s Core

The origin of our moon has long been debated.

Now, a scientist has claimed that Earth effectively ‘gave birth‘ to the moon four-and-a-half billion years ago.

A controversial new theory has been proposed that a giant explosion equivalent to 40 billion atomic bombs originating from the Earth’s core somehow led to the formation of the moon.

Planetary scientist Wim van Westrenen believes this violent event took place approximately four-and-a-half billion years ago and could answer the hotly contested question of where our moon comes from.

The scientist, from VU University in Amsterdam said that previous explanations about how the moon came to be simply do not add up.

Charles Darwin’s son, astronomer George Darwin, proposed that the early Earth spun so fast that it fell apart, hurling a part of itself into space that became the moon.





His theory was popular but was then eclipsed by the giant impact hypothesis, or ‘big splat‘, which said that a Mars-sized object crashed into an infant Earth and shattered on impact, the magazine reported.

In this theory, the debris formed the moon. However, it was largely thrown-out when astronauts brought back rocks from the Apollo moon landings.

Chemical analysis of the rocks last year by the University of Chicago found that they shared identical oxygen, silicon and potassium isotopes with Earth, hinting that the Moon shares its origin with the Earth.

Van Westeren said that taken at face value, the findings suggest that the moon was once part of the Earth that was blasted into space by an enormous explosion from the Earth’s fiery core.

To do this, he believes that there must have been a ‘massive energy kick‘ delivered quickly and he calculates that the explosion was the strength of 40 billion atomic bombs the size of those dropped on Hiroshima.

The idea that the Earth’s core harbours a huge nuclear reactor has been around for over 60 years.

There is also evidence of much smaller natural fossil reactors up to 10 metres across in West Africa that were active around 10 billion years ago.

This theory of  an internal nuclear reactor could explain why Earth gives out more energy than it receives from the sun.

However, experts have said that even if evidence of “global georeactors” was found, many scientists would need convincing that they were capable of creating the moon.

There are many conflicting ideas of exactly how the moon came to be and scientists are starting to re-question older theories.

Matija Cuk, a planetary scientist at Harvard University said: “I don’t think you can separate the moon’s formation from a giant impact.”

But he draws upon Darwin’s idea and the big splat and believes that a peculiar alignment of the sun, earth and moon is the reason why the moon orbits the Earth.

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Europa: Facts About Jupiter’s Icy Moon And Its Ocean

Europa is one of the Galilean moons of Jupiter, along with Io, Ganymede and Callisto. Astronomer Galileo Galilei gets the credit for discovering these moons, among the largest in the solar system.

Europa is the smallest of the four but it is one of the more intriguing satellites.

The surface of Europa is frozen, covered with a layer of ice, but scientists think there is an ocean beneath the surface. The icy surface also makes the moon one of the most reflective in the solar system.

Water plumes were spotted jetting from the moon in 2013, although those observations have not been repeated.

Several spacecraft have done flybys of Europa (including Pioneers 10 and 11 and Voyagers 1 and 2 in the 1970s).

The Galileo spacecraft did a long-term mission at Jupiter and its moons between 1995 and 2003.

Both NASA and the European Space Agency plan missions to Europa and other moons in the 2030s.




Galileo Galilei discovered Europa on Jan. 8, 1610. It is possible that German astronomer Simon Marius (1573-1624) also discovered the moon at the same time.

However, he did not publish his observations, so it is Galileo who is most often credited with the discovery. For this reason, Europa and Jupiter’s other three largest moons are often called the Galilean moons.

Galileo, however, called the moons the Medicean planets in honor of the Medici family.

It is possible Galileo actually observed Europa a day earlier, on Jan. 7, 1610. However, because he was using a low-powered telescope, he couldn’t differentiate Europa from Io, another of Jupiter’s moons.

It wasn’t until later that Galileo realized they were two separate bodies.

The discovery not only had astronomical, but also religious implications. At the time, the Catholic Church supported the idea that everything orbited the Earth, an idea supported in ancient times by Aristotle and Ptolemy.

Galileo’s observations of Jupiter’s moons as well as noticing that Venus went through “phases” similar to our own moon gave compelling evidence that not everything revolved around the Earth.

As telescopic observations improved, however, a new view of the universe emerged.

The moons and the planets were not unchanging and perfect; for example, mountains seen on the moon showed that geological processes happened elsewhere. Also, all planets revolved around the sun.

Over time, moons around other planets were discovered and additional moons found around Jupiter.

Marius, the other “discoverer,” first proposed that the four moons be given their current names, from Greek mythology.

But it wasn’t until the 19th century that the moons were officially given the so-called Galilean names we know them by today.

All of Jupiter’s moons are named for the god’s lovers (or victims, depending on your point of view).

In Greek mythology, Europa was abducted by Zeus, who had taken the form of a spotless white bull to seduce her.

She decorated the “bull” with flowers and rode on its back to Crete. Once in Crete, Zeus then transformed back to his original form and seduced her.

Europa was the queen of Crete and bore Zeus many children.

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