An artist's impression of the planet HATS-6b, orbiting the star, HATS-6. (Supplied: ANU) Excerpt from abc.net.au A "puffy" new planet orbiting a small, cool star has been discovered 500 light years away from Earth, by a team of scientists c...
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Vandenberg Air Force Base |
Excerpt from nbcnews.com
After years of silence on all but the most prosaic aspects of the secretive X-37B space plane program, the Defense Department has revealed that the mysterious, truck-sized craft's next mission will host an experimental new thrust system that could greatly improve the shelf life of satellites.
The X-37B program has sent its shuttle-like Orbital Test Vehicle craft into space three times for a total time in orbit of almost four years. What the spacecraft has been doing up there is anybody's guess — its creators have declined to comment except to say that everything is working properly. But a news release this week from the Air Force says in no uncertain terms that the next flight of the X-37B, set to begin next month, will be the platform for testing a Hall thruster.
Hall thrusters combine electricity and a noble gas like xenon to produce a miniscule amount of direct force — weak in comparison with thrusters that use ordinary solid fuel, but at a far lesser cost of fuel. Trading power for fuel efficiency would allow satellites and probes to make course adjustments for much longer, extending their lives and versatility. Spaceflight Now has more details on how the system works.
Of course, this sheds no light on what the last three X-37B missions were — but in light of this new information it seems more likely that it's a test bed for high-tech space experiments, and not an orbital bomber or elite spy satellite. But you never know.
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| A telescope at Lick Observatory on Mount Hamilton. (CBS) |
SAN JOSE (CBS SF) – Astronomers at the Lick Observatory atop Mount Hamilton have confirmed the existence of three planets described as “supersized Earths” orbiting a star 54 light years away.
Researchers from the University of California, University of Hawaii, the University of California Observatories and Tennessee State University have been working for years to confirm the planets were there.
The planets orbit a star called HD
7924. They orbit at a distance closer than Mercury orbits our sun (35.9 million miles), and complete their orbits in five, 15 and 24 days, respectively.“The three planets are unlike anything in our solar system, with masses seven to eight times the mass of Earth and orbits very close to their host star,” UC Berkeley graduate student Lauren Weiss said in a written statement.
The researchers used a robotic telescope called the “Automated Planet Finder,” which searches for planets around nearby stars that could be suitable for life. Most distant planets discovered by astronomers so far are gas giants like Jupiter.
Astronomers first found evidence of planets surrounding HD 7924 six years ago. The planets are not visible to the naked eye.
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| Artist's illustration of the U.S. Air Force's X-37B space plane in orbit. The mysterious spacecraft is scheduled to launch on its fourth mission on May 20, 2015. Credit: NASA Marshall Space Flight Center |
Excerpt from space.com
The United States Air Force's X-37B space plane will launch on its fourth mystery mission next month.
The unmanned X-37B space plane, which looks like a miniature version of NASA's now-retired space shuttle orbiter, is scheduled to blast off atop a United Launch Alliance Atlas V rocket from Florida's Cape Canaveral Air Force Station on May 20.
"We are excited about our fourth X-37B mission," Randy Walden, director of the Air Force Rapid Capabilities Office, said in a statement. "With the demonstrated success of the first three missions, we’re able to shift our focus from initial checkouts of the vehicle to testing of experimental payloads."
The X-37B's payloads and specific activities are classified, so it's unclear exactly what the spacecraft does while zipping around the Earth. But Air Force officials have revealed a few clues about the upcoming mission.
"The Air Force Research Laboratory (AFRL), Space and Missile Systems Center (SMC) and the Air Force Rapid Capabilities Office (AFRCO) are investigating an experimental propulsion system on the X-37B on Mission 4," Capt. Chris Hoyler, an Air Force spokesman, told Space.com via email.
"AFRCO will also host a number of advance materials onboard the X-37B for the National Aeronautics and Space Administration (NASA) to study the durability of various materials in the space environment," Hoyler added.
The Air Force owns two X-37B space planes, both of which were built by Boeing's Phantom Works division. The solar-powered spacecraft are about 29 feet long by 9.5 feet tall (8.8 by 2.9 meters), with a wingspan of 15 feet (4.6 m) and a payload bay the size of a pickup-truck bed. The X-37B launches vertically atop a rocket and lands horizontally on a runway, like the space shuttle did.
One of the two X-37B vehicles flew the program's first and third missions, which were known as OTV-1 and OTV-3, respectively. ("OTV" is short for "Orbital Test Vehicle.") The other spacecraft flew OTV-2. Air Force officials have not revealed which space plane will be going to orbit on the upcoming mission.
OTV-1 launched in April 2010 and landed in December of that year, staying in orbit for 225 days. OTV-2 blasted off in March 2011 and circled Earth for 469 days, coming down in June 2012. OTV-3 launched in December 2012 and stayed aloft for a record-breaking 675 days, finally landing in October 2014.
A recovery team processes the U.S. Air Force's X-37B space plane after the robotic spacecraft's successful landing at Vandenberg Air Force Base in California on Oct. 17, 2014. The touchdown marked the end of the X-37B’s third space mission.
Credit: Boeing
Credit: Boeing
If Air Force officials know how long OTV-4 is going to last, they're not saying.
"The X-37B is designed for an on-orbit duration of 270 days," Hoyler said. "Longer missions have been demonstrated. As with previous missions, the actual duration will depend on test objectives, on-orbit vehicle performance and conditions at the landing facility."
The secrecy surrounding the X-37B and its payloads has fueled speculation in some quarters that the vehicle could be a space weapon of some sort. But Air Force officials have repeatedly refuted that notion.
"The primary objectives of the X-37B are twofold: reusable spacecraft technologies for America's future in space, and operating experiments which can be returned to, and examined, on Earth," Air Force officials wrote in on online X-37B fact sheet.
"Technologies being tested in the program include advanced guidance, navigation and control; thermal protection systems; avionics; high-temperature structures and seals; conformal reusable insulation, lightweight electromechanical flight systems; and autonomous orbital flight, re-entry and landing."
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| The James Webb Telescope |
Excerpt from space.com
A telescope will soon allow astronomers to probe the atmosphere of Earthlike exoplanets for signs of life. To prepare, astronomer Lisa Kaltenegger and her team are modeling the atmospheric fingerprints for hundreds of potential alien worlds. Here's how:
The James Webb Space Telescope, set to launch in 2018, will usher a new era in our search for life beyond Earth. With its 6.5-meter mirror, the long-awaited successor to Hubble will be large enough to detect potential biosignatures in the atmosphere of Earthlike planets orbiting nearby stars.
And we may soon find a treasure-trove of such worlds. The forthcoming exoplanet hunter TESS (Transiting Exoplanet Survey Satellite), set to launch in 2017, will scout the entire sky for planetary systems close to ours. (The current Kepler mission focuses on more distant stars, between 600 and 3,000 light-years from Earth.)
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| Astronomer Lisa Kaltenegger |
While TESS will allow for the brief detection of new planets, the larger James Webb will follow up on select candidates and provide clues about their atmospheric composition. But the work will be difficult and require a lot of telescope time.
"We're expecting to find thousands of new planets with TESS, so we'll need to select our best targets for follow-up study with the Webb telescope," says Lisa Kaltenegger, an astronomer at Cornell University and co-investigator on the TESS team.
To prepare, Kaltenegger and her team at Cornell's Institute for Pale Blue Dots are building a database of atmospheric fingerprints for hundreds of potential alien worlds. The models will then be used as "ID cards" to guide the study of exoplanet atmospheres with the Webb and other future large telescopes.
Kaltenegger described her approach in a talk for the NASA Astrobiology Institute's Director Seminar Series last December.
"For the first time in human history, we have the technology to find and characterize other worlds," she says. "And there's a lot to learn."
Detecting life from space
In its 1990 flyby of Earth, the Galileo spacecraft took a spectrum of sunlight filtered through our planet's atmosphere. In a 1993 paper in the journal Nature, astronomer Carl Sagan analyzed that data and found a large amount of oxygen together with methane — a telltale sign of life on Earth. These observations established a control experiment for the search of extraterrestrial life by modern spacecraft."The spectrum of a planet is like a chemical fingerprint," Kaltenegger says. "This gives us the key to explore alien worlds light years away."
Current telescopes have picked up the spectra of giant, Jupiter-like exoplanets. But the telescopes are not large enough to do so for smaller, Earth-like worlds. The James Webb telescope will be our first shot at studying the atmospheres of these potentially habitable worlds.
Some forthcoming ground-based telescopes — including the Giant Magellan Telescope (GMT), planned for completion in 2020, and the European Extremely Large Telescope (E-ELT), scheduled for first light in 2024 — may also be able to contribute to that task. [The Largest Telescopes on Earth: How They Compare]
And with the expected discovery by TESS of thousands of nearby exoplanets, the James Webb and other large telescopes will have plenty of potential targets to study. Another forthcoming planet hunter, the Planetary Transits and Oscillations of stars (PLATO), a planned European Space Agency mission scheduled for launch around 2022-2024, will contribute even more candidates.
However, observation time for follow-up studies will be costly and limited.
"It will take hundreds of hours of observation to see atmospheric signatures with the Webb telescope," Kaltenegger says. "So we'll have to pick our targets carefully."
Set to see its first light in 2021, The Giant Magellan Telescope will be the world’s largest telescope.
Getting a head start
To guide that process, Kaltenegger and her team are putting together a database of atmospheric fingerprints of potential alien worlds. "The models are tools that can teach us how to observe and help us prioritize targets," she says.To start, they have modeled the chemical fingerprint of Earth over geological time. Our planet's atmosphere has evolved over time, with different life forms producing and consuming various gases. These models may give astronomers some insight into a planet's evolutionary stage.
Other models take into consideration the effects of a host of factors on the chemical signatures — including water, clouds, atmospheric thickness, geological cycles, brightness of the parent star, and even the presence of different extremophiles.
"It's important to do this wide range of modeling right now," Kaltenegger said, "so we're not too startled if we detect something unexpected. A wide parameter space can allow us to figure out if we might have a combination of these environments."
She added: "It can also help us refine our modeling as fast as possible, and decide if more measurements are needed while the telescope is still in space. It's basically a stepping-stone, so we don't have to wait until we get our first measurements to understand what we are seeing. Still, we'll likely find things we never thought about in the first place."
A new research center
The spectral database is one of the main projects undertaken at the Institute for Pale Blue Dots, a new interdisciplinary research center founded in 2014 by Kaltenegger. The official inauguration will be held on May 9, 2015."The crux of the institute is the characterization of rocky, Earth-like planets in the habitable zone of nearby stars," Kaltenergger said. "It's a very interdisciplinary effort with people from astronomy, geology, atmospheric modeling, and hopefully biology."
She added: "One of the goal is to better understand what makes a planet a life-friendly habitat, and how we can detect that from light years away. We're on the verge of discovering other pale blue dots. And with Sagan's legacy, Cornell University is a really great home for an institute like that."
Artist impression of the protoplanetary disk surrounding the young star MWC 480. ALMA has detected the complex organic molecule methyl cyanide in the outer reaches of the disk in the region where comets are believed to form. This is another indication that complex organic chemistry, and potentially the conditions necessary for life, is universal. (B. Saxton/NRAO/AUI/NSF)
Excerpt from washingtonpost.com
We're not special. Or our complex organic molecules aren't, anyway. And that's good news in the hunt for extraterrestrial life.
In a new study published Wednesday in Nature, astronomers found the first signs of the complex, carbon-based molecules that make life possible on Earth in a protoplanetary disk; the region where cosmic building blocks gather to create planets in a brand-new star system. The cyanides found there are essential to life as we know it: without them, there would be no proteins.
"We know when our own solar system was very young, it was rich in water and complex organics. We know that from observing comets," explained study author Karin Öberg, an assistant professor of astronomy at Harvard. Comets have kept the molecules of our solar system's early days locked up tight ever since, which is why scientists are so eager to study them for clues about Earth's formation. These comets show us that certain organic molecules were common in our solar system's pre-planetary days.
But this is the first time we've seen evidence of such molecules ready to seed another star system with planets that could support life.
"We're finding that we're not that special," Öberg said. "Other young solar systems in the making are also rich in the same volatiles, and in similar proportions."
And in this case, she said, being not-special is a great thing: If other solar systems formed just the way ours did, we can hope that they formed some kind of life, too.
Öberg and her colleagues found the molecules using the Atacama Large Millimeter/submillimeter Array (ALMA), a radio telescope with some pretty sweet resolution. They spotted the complex organics as much as 15 billion kilometers from the star itself, which they believe is right smack dab in the middle of the system's comet-forming region. That means the organics could get locked away in comets, just as the ones in our solar system were, and go out to seed future planets with them (as some believe was the case with Earth).
"It was kind of a chance discovery, because we weren't targeting this specific molecule," Öberg said. So she and her team need to go back and look more systematically. She also hopes they'll be able to find more systems to look at. The star they've observed -- MWC 480, located some 455 light-years away in the Taurus star-forming region -- is twice the mass of the sun, so they also hope to find some that are more similar to our host star.
"We of course want to know whether this is a really common thing or if we just lucked out on this one," Öberg said.
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Karen Teramura |
Excerpt from nbcnews.com
Astronomers have spotted a fourth star in a planetary system called 30 Ari, bringing the number of known planet-harboring quadruple-sun systems to two.
"Star systems come in myriad forms. There can be single stars, binary stars, triple stars, even quintuple star systems," study lead author Lewis Roberts, of NASA's Jet Propulsion Laboratory, said in a statement. "It's amazing the way nature puts these things together."
30 Ari lies 136 light-years from the sun in the constellation Aries. Astronomers discovered a giant planet in the system in 2009; the world is about 10 times more massive than Jupiter and orbits its primary star every 335 days. There's also a pair of stars that lie approximately 1,670 astronomical units away. (One AU is the distance between Earth and the sun — about 93 million miles, or 150 million kilometers).
The newfound star circles its companion once every 80 years, at a distance of just 22 AU, but it does not appear to affect the exoplanet's orbit despite such proximity. This is a surprising result that will require further observations to understand, researchers said.
To a hypothetical observer cruising through the giant planet's atmosphere, the sky would appear to host one small sun and two bright stars visible in daylight. With a large enough telescope, one of the bright stars could be resolved into a binary pair.
The discovery marks just the second time a planet has been identified in a four-star system. The first four-star planet, PH1b or Kepler-64b, was spotted in 2012 by citizen scientists using publicly available data from NASA's Kepler mission.
Planets with multiple suns have become less of a novelty in recent years, as astronomers have found a number of real worlds that resemble Tatooine, Luke Skywalker's home planet in the Star Wars films.
The research was published online this month in the Astronomical Journal.
Here's a good use for old military planes! Planting trees EVERYWHERE!Seed bombing or aerial reforestation is a farming technique where trees and other crops are planted by being thrown or dropped from an airplane or flying drone. The “seed bombs” are typically compressed bundles of soil containing live vegetation, which are ready to grow as soon they hit the ground.This is something that can be done on both an industrial and DIY scale, depending on the property and the situati [...]
Excerpt from csmonitor.com
Researchers have found Jupiter-scale gas giants orbiting binary stars and estimate that Earth-like planets orbiting binary stars could be as numerous as rocky planets orbiting single-star systems.
For all the sci-fi charm of watching a pair of suns sink below a distant horizon on a planet in a galaxy far, far away, conventional wisdom has held that binary-star systems can't host Earth-scale rocky planets.
As the two stars orbit each other like square-dance partners swinging arm in arm, regular variations in their gravitational tug would disrupt planet formation at the relatively close distances where rocky planets tend to appear.
Not so fast, say two astrophysicists. They argue that only are Tatooine-like planets likely to be out there. They could be as numerous as rocky planets orbiting single-star systems – which is to say, there could be large number of them.
Building rocky planets in a binary system not only is possible, it's "not even that hard," says Scott Kenyon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who along with University of Utah astrophysicist Benjamin Bromley performed the calculations.
Researchers have found Jupiter-scale gas giants orbiting binary stars and have estimated that such gas giants are likely to be as common in binary systems as they are in systems with a single star.
"If that's true, then Earth-like planets around binaries are just as common as Earth-like planets around single stars," Dr. Kenyon says. "If they're not common, that tells you something about how they form or how they interact with the star over billions of years."
The modeling study grew out of work the two researchers were undertaking to figure out how the dwarf planet Pluto and its largest moon Charon manage to share space with four smaller moons that orbit the two larger objects.
Pluto and Charon form a binary system that early in its history saw the two objects graze each other to generate a ring of dust that would become the additional moons.
The gravity the surrounding dust felt as Pluto and Charon swung about their shared center of mass would vary with clock-like precision.
Conventional wisdom held that this variable tug would trigger collisions at speeds too fast to allow the dust and larger chunks to merge into ever larger objects.
Kenyon and Dr. Bromley found that, in fact, the velocities would be smaller than people thought – no greater than the speeds would be around a single central object, where velocities are slow enough to allow the debris to bump gently and merge to build ever-larger objects.
They recognized that binary stars hosting planets are essentially scaled-up versions of the Pluto-Charon system. So they applied their calculations to a hypothetical binary star system with a circumstellar disk of dust and debris.
"The modest jostling in these orbits is the same modest jostling you'd get around a single star," Kenyon says, allowing rocky inner planets to form.
As for the Jupiter- or Neptune-scale planets found around binary stars, they would have formed farther out and migrated in over time, the researchers say, since there is too little material within the inner reaches of a circumstellar disk to build giant planets.
The duo's calculations imply that as more planets are discovered orbiting binary stars, a rising number of Tatooines will be among them.
Tatooine "was science fiction," Kenyon says. But "it's not so far from science reality."
Excerpt from huffingtonpost.comWhen astronomers began studying other solar systems in the Milky Way galaxy back in the 1990s, they noticed something peculiar: most of these systems have big planets that circle their host stars in tight orbits, a fin...
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| (Photo : NASA/ESA) In early days of solar system, Jupiter destroyed everything that came in its way, researchers have found. |
Excerpt from latimes.com
Before Mercury, Venus, Earth and Mars occupied the inner solar system, there may have been a previous generation of planets that were bigger and more numerous – but were ultimately doomed by Jupiter, according to a new study.
If indeed the early solar system was crowded with so-called super-Earths, it would have looked a lot more like the planetary systems found elsewhere in the galaxy, scientists wrote Monday in the Proceedings of the National Academy of Sciences.
As NASA’s Kepler space telescope has found more than 1,000 planets in orbit around other stars, along with more than 4,000 other objects that are believed to be planets but haven’t yet been confirmed. Kepler finds these planets by watching their host stars and registering tiny drops in their brightness – a sign that they are being ever-so-slightly darkened by a planet crossing in front of them.
In addition, ground-based telescopes have detected hundreds of exoplanets by measuring the wiggles of distant stars. Those stars wiggle thanks to the gravitational pull of orbiting planets, and the Doppler effect makes it possible to estimate the size of these planets.
The more planetary systems astronomers discovered, the more our own solar system looked like an oddball. Exoplanets – at least the ones big enough for us to see – tended to be bigger than Earth, with tight orbits that took them much closer to their host stars. In multi-planet systems, these orbits tended to be much closer together than they are in our solar system. For instance, the star known as Kepler-11 has six planets closer to it than Venus is to the sun.
Why does our solar system look so different? Astrophysicists Konstantin Batygin of Caltech and Greg Laughlin of UC Santa Cruz summed it up in one word: Jupiter.
Here’s what could have happened, according to their models:
In Solar System 1.0, the region closest to the sun was occupied by numerous planets with masses several times bigger than that of Earth. There were also planetesimals, “planetary building blocks” that formed within the first million years after the birth of the sun, Batygin and Laughlin wrote.
This is how things might have stayed if the young Jupiter had stayed put at its initial orbit, between 3 and 10 astronomical units away from the sun. (An astronomical unit, or AU, is the distance between the Earth and the sun. Today, Jupiter’s orbit ranges between 5 and 5.5 AUs from the sun.)
But Jupiter was restless, according to a scenario known as the “Grand Tack.” In this version of events, Jupiter was swept up by the currents of gas that surrounded the young sun and drifted toward the center of the solar system.
Jupiter, however, was too big to travel solo. All manner of smaller objects would have been dragged along too. With so many bodies in motion, there would have been a lot of crashes.
The result was “a collisional cascade that grinds down the planetesimal population to smaller sizes,” the astrophysicists wrote. For the most part, these planetary crumbs were swept toward the sun and ultimately destroyed, like disintegrating satellites falling back to Earth.
The planetesimals wouldn’t have been Jupiter’s only victims. Assuming the early solar system resembled the planetary systems spied by Kepler and other telescopes, there would have been “a similar population of first-generation planets,” the pair wrote. “If such planets formed, however, they were destroyed.”
Jupiter probably got about as close to the sun as Mars is today before reversing course, pulled away by the gravity of the newly formed Saturn. That would have ended the chaos in the inner solar system, allowing Earth and the other rocky planets to form from the debris that remained.
“This scenario provides a natural explanation for why the inner Solar System bears scant resemblance to the ubiquitous multi-planet systems” discovered by Kepler and other survey efforts, Batygin and Laughlin wrote.
Although their models show that this is what might have happened, they don’t prove that it actually did. But there may be a way to get closer to the truth.
The scientists’ equations suggest that if a star is orbited by a cluster of close-in planets, there won’t be a larger, farther-out planet in the same system. As astronomers find more exoplanetary systems, they can see whether this prediction holds up.
Also, if far-away solar systems are experiencing a similar series of events, telescopes ought to be able to detect the extra heat thrown off by all of the planetesimal collisions, they added.
Sadly for those hoping to find life on other planets, the pair’s calculations also imply that most Earth-sized planets are lacking in water and other essential compounds that can exist in liquid or solid form. As a result, they would be “uninhabitable,” they wrote.
Excerpt from esbtrib.com
Imagine the distinct possibility that among the billions of stars located in our vast Milky Way Galaxy, there might be a habitable zone where water probably exists and life as we know it as well.
Scientists have studied more than 150 exoplanetary systems with more than one planet circling the host star, thru the Kepler space telescope of NASA.
The new research, published in Monthly Notices of the Royal Astronomical Society, revealed the thousands of planets orbiting stars in our Milky Way galaxy. Researchers were able to compute that the stars in the Milky Way have one to three planets orbiting the habitable zone.
PhD student in the research group Astrophysics and Planetary Science at the Niels Bohr Institute at the University of Copenhagen, Steffen Kjær Jacobsen said, “In these 31 planetary systems located near the habitable zone, our calculations showed that there was an average of two planets in the habitable zone. According to statistics and the indications we have, a good share of the planets in the habitable zone will be solid planets where there might be liquid water and where life could exist.”
He added, “In 124 of the planetary systems, the Titius-Bode law fit with the position of the planets as good as or better than our own solar system. Using Titus-Bode’s law we tried to predict where there could be more planets further out in the planetary systems. But we only made calculations for planets where there is a good chance you can see them with the Kepler satellite,”
Researchers urged other scientist to look further into the records from the Kepler satellite again for more signs of the planetary systems they have predicted, as a number of them should be quite apparent.
Will this change our perception of religion? That we are not God’s only living creation?
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How Your Mind Affects Your Body
Excerpt from huffingtonpost.comWe are at last beginning to show that there is an intimate and dynamic relationship between what is going on with our feelings and thoughts and what happens in the body. A Time magazine special showed that happiness, h...
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