SpaceJibe

February 22, 2017

Major Discovery! 7 Earth-Size Alien Planets Circle Nearby Star

Astronomers have never seen anything like this before: Seven Earth-size alien worlds orbit the same tiny, dim star, and all of them may be capable of supporting life as we know it, a new study reports.

“Looking for life elsewhere, this system is probably our best bet as of today,” study co-author Brice-Olivier Demory, a professor at the Center for Space and Habitability at the University of Bern in Switzerland, said in a statement.

The exoplanets circle the star TRAPPIST-1, which lies just 39 light-years from Earth — a mere stone’s throw in the cosmic scheme of things. So speculation about the alien worlds’ life-hosting potential should soon be informed by hard data, study team members said. [Images: The 7 Earth-Size Worlds of TRAPPIST-1]

“We can expect that, within a few years, we will know a lot more about these planets, and with hope, if there is life there, [we will know] within a decade,” co-author Amaury Triaud, of the Institute of Astronomy at the University of Cambridge in England, told reporters on Tuesday (Feb. 21).

TRAPPIST-1 is an ultracool dwarf star that’s only slightly larger than the planet Jupiter and about 2,000 times dimmer than the sun.

The research team, led by Michaël Gillon of the University of Liège in Belgium, originally studied the star using the TRAnsiting Planets and PlanetesImals Small Telescope (TRAPPIST), an instrument at the La Silla Observatory in Chile. (This explains the star’s common name; the object is also known as 2MASS J23062928-0502285.)

TRAPPIST spotted regular dimming events, which the team interpreted as evidence of three different planets crossing the face of, or transiting, the star. In May 2016, Gillon and his colleagues announced the existence of these three alien worlds, called TRAPPIST-1b, TRAPPIST-1c and TRAPPIST-1d. All three, the team reported, are roughly the size of Earth and may be capable of supporting life.

The astronomers kept studying the system, using TRAPPIST and a number of other telescopes on the ground. This follow-up work suggested that the supposed TRAPPIST-1d transits were actually caused by more than one planet, and also revealed evidence of additional possible worlds in the system.

A three-week observation campaign by NASA’s Spitzer Space Telescope in September and October 2016 helped clear all of this up. Spitzer’s transit data confirmed the existence of planets b and c, but revealed that three worlds are responsible for the originally detected “TRAPPIST-1d” signal. And Spitzer also spotted two more exoplanets in the system, for a total of seven.

These seven worlds — which Gillon and his colleagues announced in the new study, published online today (Feb. 22) in the journal Nature — are all roughly Earth-size. The smallest is about 75 percent as massive as Earth, while the largest is just 10 percent heftier than our planet, the researchers said.

“This is the first time that so many planets of this kind are found around the same star,” Gillon said in Tuesday’s news conference. [Gallery: The Strangest Alien Planets]

All seven alien worlds occupy tight orbits, lying closer to TRAPPIST-1 than Mercury does to the sun. The orbital periods of the innermost six worlds range from 1.5 days to 12.4 days; the outermost planet, known as TRAPPIST-1h, is thought to complete one lap in about 20 days. (Spitzer spotted just one transit by TRAPPIST-1h, so its orbital path is not well-known.)

The six inner planets are in near-resonance, meaning their orbital periods are related to each other by a ratio of two small integers. This arrangement suggests that the worlds formed farther out in the system and then migrated in to their current positions, study team members said.

Data gathered by the various telescopes suggest that all six inner planets are rocky, like the Earth; not enough is known about planet h to determine its composition.

Because the seven alien worlds orbit so tightly, they’re probably all tidally locked, Gillon said. That is, they likely always show the same face to their host star, just as Earth’s moon only shows the “near side” to us.

And powerful gravitational tugs, both from TRAPPIST-1 and neighboring planets, could heat up the worlds’ insides considerably, leading to lots of volcanism, especially on the innermost two worlds, the researchers added.

Despite these characteristics — extreme closeness to their star and tidal locking — the TRAPPIST-1 system is a promising place to search for E.T., study team members said.

TRAPPIST-1 is so dim and cool that its “habitable zone” — that just-right range of distances where liquid water could exist — is quite close to the star. And even tidally locked planets are thought to be potentially habitable, as long as they have atmospheres that can transport heat from the day side to the night side, Gillon said.

“You’d have just a [temperature] gradient, but it’s not catastrophic for life,” he said.

Indeed, modeling work performed by the team suggests that three of the seven TRAPPIST-1 planets (e, f and g) are in the habitable zone. And it’s possible that, given the right atmospheric conditions, water — and, by extension, life as we know it — could exist on all seven, Gillon said.

Such speculation is preliminary, he and other team members stressed; more data will be needed before the TRAPPIST-1 planets’ habitability can be gauged with confidence. Such work is already underway. The team has been studying the worlds’ atmospheres with NASA’s Hubble Space Telescope, for example.

Detailed characterization — and the search for signs of possible life, such as oxygen and methane — will have to wait until more powerful instruments come online, Triaud said. But that wait shouldn’t be long: NASA’s $8.8 billion James Webb Space Telescope is slated to launch in late 2018, and huge, capable ground-based scopes such as the European Extremely Large Telescope and the Giant Magellan Telescope are scheduled to come online in the early to mid-2020s.

“I think that we’ve made a crucial step toward finding [out] if there is life out there,” Triaud said. “Here, if life managed to thrive, and releases gases similar to that that we have on Earth, then we will know.”

Characteristics of the seven TRAPPIST-1 worlds, compared to the rocky planets in our solar system. (NASA/JPL-Caltech)

Characteristics of the seven TRAPPIST-1 worlds, compared to the rocky planets in our solar system. (NASA/JPL-Caltech)

If there were life-forms on one or more of the TRAPPIST-1 worlds, what would they see? Because of the star’s dimness, even daytime skies would never get brighter than Earth’s are just after sunset, Triaud said. (Still, the air would be warm, because most of TRAPPIST-1’s light is radiated in infrared, not visible, wavelengths.) And everything would be suffused in a sort of salmon-colored glow.

“The spectacle would be beautiful, because every now and then you would see another planet, maybe about as big as twice [Earth’s] moon in the sky, depending on which planet you were on,” Triaud said.

Future work may help determine just how common such seemingly exotic vistas are in the sun’s neck of the cosmic woods.

“About 15 percent of the stars in our neighborhood are very cool stars like TRAPPIST-1,” Demory said in the same statement. “We have a list of about 600 targets that we will observe in the future.”

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February 11, 2017

Ten reasons why NASA’s James Webb Space Telescope will kick some cosmic butt

Filed under: Big Bang, Cool, Cosmology, Extraterrestrial Life, Gadgets, Space Exploration — bferrari @ 3:05 pm

Here are ten amazing facts about the JWST that you might not have known.

James Webb Space Telescope

James Webb Space Telescope

1. It’s as big as a tennis court

With a sunshield 22 metres (72 feet) in length, the size of a tennis court, and a mirror 6.5 metres (21 feet) wide the JWST, which is due to launch in October 2018, is over twice the size of the Hubble Space Telescope, making it the largest space telescope ever launched.
2. The mirrors are coated in a golf ball’s worth of gold
The JWST’s mirrors are covered in gold to optimise them for infrared light, with the gold further protected by a thin layer of glass. The thickness of this gold coating is 0.00001 centimetres across the 25 square-metre mirror’s surface, and in total the gold weighs 48.25 grams, roughly equivalent to the weight of a golf ball.
3. It’ll be about four times further from Earth than the Moon

The JWST will take about a month to reach a position 1.5 million kilometres (930,000 miles) from Earth known as Lagrange point 2, or L2. Here the telescope’s observations will be unhindered by Earth and the Moon although, if it malfunctions (as happened with Hubble), we currently have no way to go and fix it.

 

4. It could see a penny 24 miles away

The angular resolution of the JWST, which is the sharpness of the images, is incredibly precise. It can see at a resolution of 0.1 arc-seconds, which means that it could resolve a penny 24 miles (40 kilometres) away or a football 340 miles (550 kilometres) away.

5. It could find water on exoplanets

One of the JWST’s most notable abilities is that it will be able to detect planets around nearby stars by measuring infrared radiation, and it will even be able to measure the atmospheres of exoplanets by studying the starlight that passes through. By doing this it will be able to determine if an exoplanet has liquid water on its surface.

6. It’s seven times more powerful than the Hubble Space Telescope

The giant mirror of the JWST is made of 18 individual hexagonal segments composed of lightweight beryllium. It is almost three times the size of Hubble’s mirror, boasting a light-collecting area seven times greater, but both mirrors weigh almost the same owing to the lighter materials used on the JWST’s mirror.

7. It’ll see the first light of the universe

One of the goals of the JWST is to observe the first stars and galaxies that formed just a few hundred million years after the Big Bang, an era of the universe that is not fully understood. The telescope will be sensitive to infrared light, which will enable it to do this.

8. It will unfold to its massive size in space

Many features of the JWST, including its giant mirrors and sunshield, are designed to be launched on a rocket in a smaller payload. The telescope will launch in a compact outfit and will unfold in its full configuration once it reaches space.

9. One side is hotter than Death Valley, the other is colder than Antarctica

The side of the JWST that will always face the Sun, the bottom of the sunshield, will reach temperatures of 85°C (185 °F). The other side, which houses the mirrors and science instruments, will operate at a much nippier -233°C (-388 °F).

10. It could keep working for a decade

The official mission lifespan for the JWST is between five and ten years. The telescope is limited by the amount of fuel it has on board used to maintain its position, which will be enough for a ten-year lifetime. Of course, other factors like budget cuts or malfunctions could end the mission earlier.

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September 19, 2016

NASA is building the largest rocket of all time for a 2018 launch

Filed under: Cool, Inner Solar System, Mars, Military, Space Exploration, Space Ships — bferrari @ 8:54 am
Artist's rendering of a blueprint of the completed Space Launch System. (NASA/MSFC)

Artist’s rendering of a blueprint of the completed Space Launch System. (NASA/MSFC)

NASA has worked on some inspiring interplanetary projects in the last few years, but few have been as ambitious as the simply-named Space Launch System, a new rocket that will be the largest ever built at 384 feet tall, surpassing even the mighty Saturn V(363 feet), the rocket that took humanity to the moon. It will also be more powerful, with20 percent more thrust using liquid hydrogen and oxygen as fuel. Last week, NASA announced that the Space Launch System, SLS for short, is on track to perform its first unmanned test launch in 2018. The larger goal is to carry humans into orbit around an asteroid, and then to Mars by the 2030s. After that, NASA says the rocket could be used to reach Saturn and Jupiter.

At the moment, even getting off the ground would be progress: since the retirement of the Space Shuttle in 2011, NASA has been left without any domestic capability to launch American astronauts into space; instead it has been purchasing rides for them aboard Russian Soyuz spacecraft at high cost. While SpaceX and other private companies are working furiously to provide their own human passenger spacecraft for travel into Earth’s orbit, NASA wants to go even further. The agency has begun testing models of the SLSand initial construction of some the major components. It says the first test flight will have an initial cost of $7 billion. The SLS will also be reusing some leftover parts from the inventory of the retired Space Shuttle, including its engines.

However, as with many large NASA projects, the SLS has already been delayed from an initial flight in 2017, and lawmakers in Congress, who must approve NASA’s budget, areconcerned about further delays and cost overruns. Whether NASA is able to keep the project on track remains to be seen, but at the moment, it’s all systems go. Check out the progress and promise in photos and conceptual illustrations below.

NASA engineers used a 67.5-inch model to test how environmental factors including wind and water would affect the rocket on the launchpad. (Credit: NASA/LaRC)

NASA engineers used a 67.5-inch model to test how environmental factors including wind and water would affect the rocket on the launchpad. (Credit: NASA/LaRC)

 

Artist's rendering of the Space Launch System sitting on the launchpad at Kennedy Space Center in Cape Canaveral, Florida. (NASA/MSFC)

Artist’s rendering of the Space Launch System sitting on the launchpad at Kennedy Space Center in Cape Canaveral, Florida. (NASA/MSFC)

More awesome images here:

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August 24, 2016

‘Second Earth’ exoplanet found right under our noses – just four light years away

Filed under: Cool, Cosmology, Exoplanets, Extraterrestrial Life, Life, Outer Solar System — bferrari @ 2:29 pm

Proxima b is a likely target for Starshot project

 

Artist's impression of Proxima b and Proxima Centauri [Photo credit: ESO/M. Kornmesser]

Artist’s impression of Proxima b and Proxima Centauri [Photo credit: ESO/M. Kornmesser]

Rumours that a terrestrial planet orbiting Proxima Centauri – the Sun’s closest neighbour – may be Earth-like have been confirmed today in a paper published in Nature.

The possibility that extraterrestrial life may exist next door was first reported last week in Der Spiegel, a German weekly news magazine.

Excitement bubbled over and the European Southern Observatory refused to confirm or deny the rumours, as it wanted to keep the research under wraps. But it eventually gave in, and announced that all details would be revealed at the end of August.

Tantalising evidence shows the candidate planet, known as Proxima b, may be small and rocky and lies in the habitable zone around its star – just like Earth.

Proxima b’s equilibrium temperature is within the range where water may be in liquid form on its surface, the researchers believe.

It orbits around Proxima Centauri, a red-dwarf located only 4.25 light years away in the closest star system, Alpha Centauri. It’s much closer to its star than the Earth is to the Sun at 0.05 astronomical units away, so a year only lasts 11.2 days.

How Earth-like is Proxima b?

Although the signs are promising, it’s completely hypothetical that Proxima b is Earth-like, the researchers said.

Infographic compares the orbit of Proxima b around Proxima Centauri with the same region of the Solar System [Photo credit: ESO/M. Kornmesser/G. Coleman]

Infographic compares the orbit of Proxima b around Proxima Centauri with the same region of the Solar System [Photo credit: ESO/M. Kornmesser/G. Coleman]

Professor Hugh Jones, who was part of the large team analysing data from Proxima b and a physics lecturer at the University of Hertfordshire, told The Register: “Saying it’s more Earth-like than just its mass is speculative. It’s exciting because it’s the first time anybody has found a planet around the closest stars. We have been looking for ages.”

Sixteen years ago, researchers first spotted a signal that Proxima Centauri could be harbouring a planet. It took a while for confirmation because of the faint signal, Jones said.

Proxima Centauri is a faint star with a luminosity much lower than the Sun. Its surface temperature is 3,050 kelvin, as compared to the Sun’s 5,777 kelvin. Researchers used Doppler spectroscopy to measure changes in the velocity of the star caused by a gravitationally bound body that was orbiting around it.

The Doppler method is an effective way of detecting exoplanets, but it doesn’t give much information about the planet itself. Many properties, including Proxima b’s radius, are currently unknown.

Journey to Alpha Centauri

That doesn’t dampen the spirits of scientists and engineers working on the Breakthrough Starshot project, however.

Starshot was launched in April 2016 by Russian billionaire Yuri Milner and acclaimed physicist Stephen Hawking. The project aims to send tiny “nanocrafts” to the Alpha Centauri system, about 25 trillion miles away, at 15 to 20 per cent of the speed of light.

Speaking about the research, Professor Avi Loeb, Chairman of the Breakthrough Starshot advisory committee and researcher at Harvard University, told The Register: “We will celebrate this important discovery within the Starshot team.”

“The discovery of the habitable planet around the nearest star, Proxima Centauri, is strategically important for motivating the Breakthrough Starshot initiative, since it provides an obvious target for a flyby mission.

“A spacecraft equipped with a camera and various filters could take color images of the planet and infer whether it is green (harboring life as we know it), blue (with water oceans on its surface) or just brown (dry rock),” Loeb said.

The bright star is Alpha Centauri AB and Proxima Centauri is the fainter red dwarf star  [Photo credit: Digitized Sky Survey 2, Acknowledgement: Davide De Martin/Mahdi Zamani]

The bright star is Alpha Centauri AB and Proxima Centauri is the fainter red dwarf star [Photo credit: Digitized Sky Survey 2, Acknowledgement: Davide De Martin/Mahdi Zamani]

Proxima b has another property that increases its chances of harbouring life, Loeb, who was uninvolved in the research, said.

“Low-mass stars burn nuclear fuel at a slower rate, so they are more likely to live longer. Proxima Centauri is smaller than our Sun and will live about a thousand times longer. This means that any life on the planet has a longer time to develop and survive,” Loeb told The Register.

“Hence, a habitable rocky planet around Proxima would be the most natural location to where our civilization could aspire to move after the Sun will die, five billion years from now.”

The prospect of nanobots venturing to Proxima b to take photos is still very far away, and with current technology it’s still difficult to resolve Proxima b from its star. But with better telescopes and sensitive instruments being built in the next decade, the close proximity of Proxima b gives researchers their best fighting chance yet of looking out for extraterrestrial life.

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June 23, 2016

NASA reveals the X-57, its electric plane project

Filed under: Cool, Gadgets, Military, Space Ships — bferrari @ 2:57 pm

1466451753763Artist’s concept of the X-57. (NASA Langley/Advanced Concepts Lab, AMA, Inc.)

 

An electric plane project is in the works at NASA, and the new aircraft is called the X-57. It’s an initiative the space agency hopes will demonstrate that electric-powered aviation can be environmentally friendly, quiet, and quick.

Made out of a modified Italian-designed plane, the X-57 will have a skinny wing with a total of 14 battery-powered motors, and because it won’t run on gas, it won’t produce exhaust from burnt fossil fuels. NASA said that having multiple small engines means the X-57 will need less energy to cruise at a speed of 175 mph.

And while traditional fuel-burning airplanes need to cruise slower than their maximum speed to be the most fuel-efficient, the space agency says that that isn’t the case with an electric-powered plane.

Related: Solar Impulse 2 attempts fuel-free trans-Atlantic flight

The “X” designation in the plane’s name places it the tradition of experimental aircraft, with the first, the X-1, the name of the plane that broke the sound barrier in 1947 at the hands of Chuck Yeager.

“With the return of piloted X-planes to NASA’s research capabilities – which is a key part of our 10-year-long New Aviation Horizons initiative – the general aviation-sized X-57 will take the first step in opening a new era of aviation,” Charles Bolden, the NASA administrator, said in a statement.

Related: Hang glider aims to break long-distance flight record

The space agency may in fact make more than one aircraft in the program. “As many as five larger transport-scale X-planes also are planned as part of the initiative,” NASA says. The plane is also called Maxwell, named after James Clerk Maxwell, a vanguard in the study of electromagnetism.

The power of clean energy in aviation is in the spotlight lately, as the sun-powered aircraft Solar Impulse 2took off from New York’s Kennedy airport at 2:30 a.m. EDT Monday, on a daring trip across the Atlantic Ocean— the latest leg of a record-breaking solar-powered journey around the world meant to showcase the power of renewable energy.

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June 3, 2016

Did our sun steal ‘Planet 9’ from another star?

Filed under: Cool, Dwarf Planets, Exoplanets, Kuiper Belt, Near Earth Objects (NEOs), Outer Solar System — bferrari @ 8:35 am

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There are eight planets in our solar system, and have been officially ever since Pluto was reclassified as a dwarf planet in 2006. But what if there was a ninth planet, billions of miles past Neptune?

Earlier this year, researchers from CalTech announced that they had found signs of the planet, which is referred to a “Planet 9,” through modeling and computer simulations. If a ninth planet were out there, it would be a big one— ten times the mass of Earth— and very, very far away, completing just one orbit around the sun as slowly as perhaps every 10,000 to 20,000 years.

Related: Scientists may have just found a ninth planet and it’s massive

Now, scientists from Lund University in Sweden have used computer simulations to propose a new theory about how Planet 9— if it exists— came to be a member of the solar system. They propose that it was stolen by our sun from another star about 4.5 billion years ago.

“What we were arguing was that you could create this [Planet 9] around another star, and then the sun could capture it, in a close encounter,” Alexander Mustill, a researcher in the department of astronomy and theoretical physics at Lund University, explained in a video about the theory.

Related: NASA identifies 1,284 new exoplanets, most ever announced at once

“We argue that this is how you could put this planet on a wide orbit around the sun,” he added. “You first create it around another star, and then the sun captures it.”

The researchers argue that this would make this planet an exoplanet, which is the term scientists use to describe planets in other star systems beyond our own. Just last month, NASA announced that they had added over 1,200 new exoplanets to the official roster, all of them discoveries from the Kepler spacecraft that had been validated through a new statistical method.

Related: Planet discovery fuels interest in mythical world of deep space

“It’s very exciting to this that there might be an extrasolar planet in our own solar system,” Mustill said.

The study proposing the new theory about Planet 9 was published online in the Monthly Notices of the Royal Astronomical Society in April.

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May 3, 2016

Three newly discovered Earth-sized planets may be prime spot to hunt alien life

Filed under: Cool, Exoplanets, Extraterrestrial Life, Space Exploration — bferrari @ 10:56 am
The artist’s impression provided by European Southern Observatory on May 2, 2016 shows an imagined view from the surface one of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth that were discovered using the TRAPPIST telescope at ESO’s La Silla Observatory. (ESO/M. Kornmesser via AP)

The artist’s impression provided by European Southern Observatory on May 2, 2016 shows an imagined view from the surface one of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth that were discovered using the TRAPPIST telescope at ESO’s La Silla Observatory. (ESO/M. Kornmesser via AP)

Astronomers searching for life beyond our solar system may need to look no farther than a little, feeble nearby star.

A Belgian-led team reported Monday that it’s discovered three Earth-sized planets orbiting an ultra-cool dwarf star less than 40 light-years away. It’s the first time planets have been found around this type of star — and it opens up new, rich territory in the search for extraterrestrial life.

Because this star is so close and so faint, astronomers can study the atmospheres of these three temperate exoplanets and, eventually, hunt for signs of possible life. They’re already making atmospheric observations, in fact, using NASA’s Spitzer Space Telescope. The Hubble Space Telescope will join in next week.

Altogether, it’s a “winning combination” for seeking chemical traces of life outside our solar system, said Massachusetts Institute of Technology researcher Julien de Wit, a co-author of the study, released by the journal Nature.

The star in question — named Trappist-1 after the Belgian telescope in Chile that made the discovery — is barely the size of Jupiter and located in the constellation Aquarius.

Other exoplanet searches have targeted bigger, brighter stars more like our sun, but the starlight in these cases can be so bright that it washes out the signatures of planets. By comparison, cool dwarf stars that emit infrared light, like Trappist-1, make it easier to spot potential worlds.

University of Liege astronomers in Belgium — lead study authors Michael Gillon and Emmanuel Jehin — built the Trappist telescope to observe 60 of the nearest ultra-cool dwarf stars. The risky effort paid off, de Wit noted in an email.

“Systems around these tiny stars are the only places where we can detect life on an Earth-sized exoplanet with our current technology,” Gillon said in a statement. “So if we want to find life elsewhere in the universe, this is where we should start to look.”

The two inner exoplanets take between 1.5 and 2.4 days to orbit the Trappist-1 star. The precise orbit time of the third planet is not known, but it falls somewhere between 4.5 days and 73 days. That puts the planets 20 times to 100 times closer to their star than Earth is to our sun, Gillon noted. The setup is more similar in scale to Jupiter’s moons than to our solar system, he added.

Although the two innermost planets are very close to the star, it showers them with only a few times the amount of energy that Earth receives from our own sun. The third exoplanet farther out may receive significantly less of such radiation than Earth does.

The astronomers speculate the two inner exoplanets may have pockets where life may exist, while the third exoplanet actually might fall within the habitable zone — real estate located at just the right distance from a star in order to harbor water and, possibly, life.

Spitzer and Hubble should answer whether the exoplanets have large and clear atmospheres, according to de Wit. They also might be able to detect water and methane, if molecules are present.

Future observatories, including NASA’s James Web Space Telescope set to launch in 2018, should unearth even more details.

Gillon and his colleagues identified the three exoplanets by observing regular dips in the infrared signals emanating from the Trappist-1 star, some 36 light-years away. A single light-year represents about 6 trillion miles.

The astronomers conducted the survey last year using the Transiting Planets and Planetesimals Small Telescope, or Trappist. It’s considered a prototype for a more expansive European project that will widen the search for potentially habitable worlds to 500 ultra-cool stars. This upcoming project is dubbed Speculoos — short for Search for Habitable Planets Eclipsing Ultra-Cool Stars.

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May 1, 2016

Newly Discovered Star Has an Almost Pure Oxygen Atmosphere

Filed under: Cool, Cosmology, Wierd — bferrari @ 5:25 pm
An artist's depiction of white dwarf stars Sirius A and B.

An artist’s depiction of white dwarf stars Sirius A and B.

A newly discovered star is unlike any ever found. With an outermost layer of 99.9 percent pure oxygen, its atmosphere is the most oxygen-rich in the known universe. Heck, it makes Earth’s meager 21 percent look downright suffocating.

The strange stellar oddity is a radically new type of white dwarf star, and was discovered by a team of Brazilian astronomers led by Kepler de Souza Oliveira at the Federal University of Rio Grande do Sul in Brazil. The star is unique in the known pool of 32,000 white dwarf stars, and is the only known star of any kind with an almost pure oxygen atmosphere. The new white dwarf has a mouthful of a name—SDSSJ124043.01+671034.68—but has been nicknamed ‘Dox’ (pronounced Dee-Awks) by Kepler’s team. The discovery was reported today in a paper in the journal Science.

THIS WHITE DWARF WAS INCREDIBLY UNEXPECTED.

“This white dwarf was incredibly unexpected,” says Kepler, “And because we had no idea anything like it could even exist, that made it all the more difficult to find.”

Missing Gas

Here’s a quick refresher: White dwarfs like Dox are the antiques of the cosmos. They’re the hyper-dense husks left over when stars largely sputter out of hydrogen and helium fuel. All but the largest 3 percent of stars end up as white dwarfs. Although Dox is only slightly bigger than our home planet, it’s 60 percent the mass of our sun.

Boris Gänsicke, an astronomer at the University of Warwick, in the UK, who was not involved in Dox’s discovery, confirms that the “exotic white dwarf… has an almost pure oxygen atmosphere, diluted only by traces of neon, magnesium, and silicon,” he writes in an essay accompanying the Science paper. “This chemical composition is unique among known [white dwarfs] and must arise from an extremely rare process.”

So, what makes Dox’s oxygen rich atmosphere so unexpected? Kepler explains that Dox presents more than a couple mysteries. For one, almost all other white dwarfs in the sky have an atmosphere thick with light elements like hydrogen and helium. These light elements are the final dregs of the star’s elemental fusion fuel that survived the star’s earlier life-cycle. Simply because of their weight, these light elements naturally float to the top of white dwarfs.

“What happened to all these light elements?” asks Kepler “How did they all get stripped away?”

Kepler also explains that although traces of heavier elements like carbon and oxygen can be detected in about one out of every five white dwarfs, it’s never quite like this. A white dwarf’s atmosphere is never purely one element, and is often diluted in a pool of lighter elements. Perhaps most perplexing, when oxygen atoms are found, they’re spied in far heavier white dwarfs. Smaller white dwarfs evolve from smaller stars, which don’t fuse together atoms into oxygen as they collapse. By all calculations, Dox would have had to be roughly double its weight to have even forged oxygen atoms in its earlier life. “You have to wonder where this oxygen even came from,” says Kepler.

In short, by simply being so weird, Dox completely defies our general, scientific understanding of how stars evolve and eventually form into white dwarfs. But Kepler suggests that maybe this shouldn’t be all that surprising. That’s because, he argues, scientists have often ignored the wacky results that can come about when stars grow and evolve while locked in a binary dance with other stars—rather than alone.

“I think the main problem is that we [astronomers] have dedicated the last 50 years to calculate the evolution of stars that are not interacting with each other, when at least 30 percent of stars interact with a binary companion,” he says.

Kepler believes Dox looks so strange because of an unlikely binary origin-story. His rough theory goes like this:

At some point Dox may have been a larger white dwarf, locked in a twirling ballet with another star much like our own Sun. These two stars were about the same distance apart as the Sun and Venus are. As Dox’s dance partner started to sputter out of Hydrogen fuel, it formed what’s called a red giant. It expanded rapidly—becoming so big that it actually engulfed the white dwarf in its outermost layer of gas. Kepler believes Dox would have started siphoning off the red giant’s gas onto itself. At some point during that siphoning process, “when it reached a few million degrees, it exploded. That explosion threw all types of matter out. That’s when [Dox] might have lost all its hydrogen and helium. This type of situation is known to have happened with other stars, although it’s never been seen to leave just oxygen,” he says.

The World’s Most Boring Job

Dox was discovered in a data mountain of 4.5 million individual star observations, collected over the last 15 years by a New Mexico observatory in a project called the Sloan Digital Sky Survey. It was found by way of a process so grueling that its initial discoverer—one of Kepler’s undergraduate students Gustavo Ourique—deserves a mention.

Ourique was looking for strange, new types of white dwarfs in a data pile of 300,000 possible observations. These observations are simple graphs about what colors of light came from each pinpoint source (called a spectral graph). Because a computer isn’t easily programmed with such a vague task as “find something weird and cool,” Ourique was challenged with the grunt-work task of physically looking at printed out pages of all 300,000 graphs.

“After a few months he could filter a one or two thousand each day, like reading a book” says Kepler. Yeah, but what a heartbreakingly boring book. That is, at least until it gets thrilling, because after half a year of scanning, and toward the end of the 300,000 graphs, Ourique came across Dox. Because of it’s oxygen atmosphere, Dox’s spectral graph looked truly unique, and he brought it to Kepler.

Ourique, man, you are a hero.

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April 25, 2016

Air Force maglev sled breaks record at 633 mph

Filed under: Cool, Government Policies, Military — bferrari @ 8:49 am

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In the New Mexico desert last month, a rocket-powered magnetically-levitated sled broke a world record after it blasted down a track at 633 miles per hour, faster than the cruising speed of a 747.

The test occurred at Holloman Air Force Base on a special 2100-foot track on March 4. Air Force video shows the one-ton vehicle rocketing down the track, a fiery, dusty plume behind it.

“We have a magnetically-levitated sled, where we use a very cold liquid helium to essentially levitate the sled via superconducting magnetics,” Lt. Col. Shawn Morgenstern, the commander of the 846th Test Squadron, said in the video.

“The test today was significantly faster than any test that we’ve previously done,” Morgenstern added.

The Air Force said that the sled accelerated at a rate of 928 feet per second. Before this test, the sled had reached 513 mph.

Magnetic levitation systems allow for vehicles to travel in a very low-friction environment, permitting incredibly fast speeds— last year, a Japanese maglev train traveled at 374 mph. And Elon Musk, the CEO of Tesla Motors and SpaceX, has proposed a system called the Hyperloop that would use a related technology to move people or cargo at breathtaking speeds.

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April 21, 2016

Why a Chip That’s Bad at Math Can Help Computers Tackle Harder Problems

Filed under: Cool, Gadgets — bferrari @ 1:54 pm

DARPA funded the development of a new computer chip that’s hardwired to make simple mistakes but can help computers understand the world.

Your math teacher lied to you. Sometimes getting your sums wrong is a good thing.

This chip can’t get its arithmetic right, but could make computers more efficient at tricky problems like analyzing images.

This chip can’t get its arithmetic right, but could make computers more efficient at tricky problems like analyzing images.

Why a Chip That’s Bad at Math Can Help Computers Tackle Harder Problems
DARPA funded the development of a new computer chip that’s hardwired to make simple mistakes but can help computers understand the world.
by Tom Simonite April 14, 2016
So says Joseph Bates, cofounder and CEO of Singular Computing, a company whose computer chips are hardwired to be incapable of performing mathematical calculations correctly. Ask it to add 1 and 1 and you will get answers like 2.01 or 1.98.

The Pentagon research agency DARPA funded the creation of Singular’s chip because that fuzziness can be an asset when it comes to some of the hardest problems for computers, such as making sense of video or other messy real-world data. “Just because the hardware is sucky doesn’t mean the software’s result has to be,” says Bates.

A chip that can’t guarantee that every calculation is perfect can still get good results on many problems but needs fewer circuits and burns less energy, he says.

Bates has worked with Sandia National Lab, Carnegie Mellon University, the Office of Naval Research, and MIT on tests that used simulations to show how the S1 chip’s inexact operations might make certain tricky computing tasks more efficient. Problems with data that comes with built-in noise from the real world, or where some approximation is needed, are the best fits. Bates reports promising results for applications such as high-resolution radar imaging, extracting 3-D information from stereo photos, and deep learning, a technique that has delivered a recent burst of progress in artificial intelligence.

In a simulated test using software that tracks objects such as cars in video, Singular’s approach was capable of processing frames almost 100 times faster than a conventional processor restricted to doing correct math—while using less than 2 percent as much power.

Bates is not the first to pursue the idea of using hand-wavy hardware to crunch data more efficiently, a notion known as approximate computing (see “10 Breakthrough Technologies 2008: Probabilistic Chips”). But DARPA’s investment in his chip could give the fuzzy math dream its biggest tryout yet.

Bates is building a batch of error-prone computers that each combine 16 of his chips with a single conventional processor. DARPA will get five such machines sometime this summer and plans to put them online for government and academic researchers to play with. The hope is that they can prove the technology’s potential and lure interest from the chip industry.

DARPA funded Singular’s chip as part of a program called Upside, which is aimed at inventing new, more efficient ways to process video footage. Military drones can collect vast quantities of video, but it can’t always be downloaded during flight, and the computer power needed to process it in the air would be too bulky.

It will take notable feats of software and even cultural engineering for imprecise hardware to take off. It’s not easy for programmers used to the idea that chips are always super-precise to adapt to ones that aren’t, says Christian Enz, a professor at the Swiss Federal Institute of Technology in Lausanne who has built his own approximate computing chips. New tools will be needed to help them do that, he says.

But Deb Roy, a professor at the MIT Media Lab and Twitter’s chief media scientist, says that recent trends in computing suggest approximate computing may find a readier audience than ever. “There’s a natural resonance if you are processing any kind of data that is noisy by nature,” he says. That’s become more and more common as programmers look to extract information from photos and video or have machines make sense of the world and human behavior, he adds.

 

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