NASA’s steady reconnaissance of Mars with the Curiosity rover has produced another major discovery: evidence of an ancient lake — with water that could plausibly be described as drinkable — that was part of a long-standing, wet environment that could have supported simple forms of life.
Scientists have known that the young Mars was more Earthlike than the desert planet we see today, but this is the best evidence yet that Mars had swimming holes that stuck around for thousands or perhaps millions of years. (It would have been very chilly — bring a wet suit.)
Scientists had announced this year that they’d found signs of an ancient, fresh-water lake within Gale Crater, but the new reports provide a much more detailed analysis, including the first scientific measurements of the age of rocks on another planet. The research suggests that Martian winds are sand-blasting rock outcroppings and creating inviting places to dig into rocks that may retain the kind of organic molecules associated with ancient microbes.
Gale Crater is in an area with rocks about 4.2 billion years old. The lake, which scientists think existed a little more than 3.5 billion years ago, was roughly the size and shape of one of New York’s Finger Lakes. The freshwater lake may have come and gone, and sometimes been iced over, but the new research shows that the lake was not some momentary feature, but rather was part of a long-lasting habitable environment that included rivers and groundwater.
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Wormholes — shortcuts that in theory can connect distant points in the universe — might be linked with the spooky phenomenon of quantum entanglement, where the behavior of particles can be connected regardless of distance, researchers say.
These findings could help scientists explain the universe from its very smallest to its biggest scales.
Scientists have long sought to develop a theory that can describe how the cosmos works in its entirety. Currently, researchers have two disparate theories, quantum mechanics and general relativity, which can respectively mostly explain the universe on its tiniest scales and its largest scales. There are currently several competing theories seeking to reconcile the pair.
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Racing high over the Sahara at 5 miles per second, protected from the desert’s parched endlessness and soaking in its sere beauty, I saw Khartoum, the city where the White and Blue Nile rivers meet. I turned my head left and followed the river downstream to Cairo and the Mediterranean. Twisting weightlessly back to my right, I could pick out sunlight glinting off the waters of Lake Tana and Lake Victoria, the Nile’s headwaters. Explorers from the early Greeks to Queen Victoria’s David Livingstone had toiled and failed to find what I could see at a glance. Impressive on its own—even more so since I had been over Winnipeg, on the edge of the Canadian prairies, just 20 minutes earlier.
Circling Earth so fast makes you think. When you look out the window of a spaceship, you see entire countries, vast swaths of continents. One turn of the head covers what once took thousands of years to traverse at ground level. Historians and archaeologists estimate that human beings started migrating from Africa to Asia about 70,000 years ago, and to Australia 20,000 years after that. We went to the New World of the Americas about 30,000 years ago. All told, from the first dissatisfied teenager’s steps away from home, it took about 50,000 years to walk to the far corners of the planet.
Technology helped us pick up the pace. By the 1870s, new railways across the US and India and the opening of the Suez Canal made it seem completely plausible that the fictional Phileas Fogg and his valet could circle the world in 80 days. In 1911, Roald Amundsen reached the farthest end of Earth and stood atop the South Pole; 50 years later, the Soviet Union sent Yuri Gagarin around that same world in a little more than 80 minutes. And since November 2000, astronauts on the International Space Station have circled our planet 16 times a day—that’s about 75,000 times around and counting.
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Europe next week will launch a trio of hi-tech satellites to explore something that may seem utterly mundane: Earth’s magnetic field.
After all, magnetism has been with us for billions of years.
We harness it in innumerable ways, in navigation and electrical devices. What’s new?
Well, plenty, actually.
If all goes well, the 230-million-euro ($276-million) Swarm mission will explain some of the weird things happening to the planet’s magnetism.
And they are more than just curiosities.
“Earth’s magnetic field is a very important thing. It makes life possible on Earth by providing shelter against radiation from space,” said Albert Zaglauer, project manager at Astrium, which made the three satellites.
The field is fickle, he said.
“The magnetic pole is changing, and the magnetic field is changing too. Why?”
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Wow! That was our reaction to seeing this picture of a light show aboard the International Space Station. After confirming with NASA that the images circulating lately on social media are real, we were directed to the Japan Aerospace Exploration Agency (JAXA), who co-ordinated this experiment.
The work is called “Auroral Oval Spiral Top” and was done in the Kibo module on May 12, 2011, JAXA said. This was the second version of the experiment, which initially ran April 30, 2009 during Expedition 19.
“Auroral Oval Spiral Top uses a spinning top that has arms illuminating with LED linear light sources and point light sources. Various movements of the spinning top floating in microgravity show aurora-like light traces,” JAXA stated on a web page about the experiment.
The project, JAXA added, is “designed to produce aurora-like luminescence traces using a spinning top with both linear and point light sources. In microgravity, the center of gravity of the spinning top continuously and randomly moves while it is spinning. Using the characteristics of the top in microgravity, the project tries to produce various light arts using its unexpected movements/spins, by changing attaching locations of its arms and weights.”
Space is vast, but it may not be so lonely after all: A study finds the Milky Way is teeming with billions of planets that are about the size of Earth, orbit stars just like our sun, and exist in the Goldilocks zone — not too hot and not too cold for life.
Astronomers using NASA data have calculated for the first time that in our galaxy alone, there are at least 8.8 billion stars with Earth-size planets in the habitable temperature zone.
The study was published Monday in the journal Proceedings of the National Academy of Science.
For perspective, that’s more Earth-like planets than there are people on Earth.
As for what it says about the odds that there is life somewhere out there, it means “just in our Milky Way galaxy alone, that’s 8.8 billion throws of the biological dice,” said study co-author Geoff Marcy, a longtime planet hunter from the University of California at Berkeley.
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Why send jellyfish to space? Well, because it’s awesome which is true of anything involving space. But mostly because of little crystals that they keep in their bodies, and what these crystals can tell us about long-term human space travel.
When a jellyfish grows, it forms calcium sulfate crystals at the margin of its body (termed a bell). These crystals are surrounded by a little cell pocket, coated in specialised hairs, which are equally spaced around the bell. When jellyfish turn, the crystals roll down with gravity to the bottom of the pocket, moving the cell hairs, which in turn send signals to nerve cells. In this way, jellyfish are able to sense their way up and down. All they need for this to happen is gravity.
Humans have gravity sensing structures too, and therein lies the crux: in space with no gravity, will these structures grow normally? If humans ever want to colonise places in deep space, then we may need to have kids in zero gravity. Will these kids develop normal gravity sensing, even after growing up without it?
For jellyfish, at least, things aren’t so good. After developing in space, these astronaut jellyfish have a hard life back on Earth. While development of the sensory pockets appears normal, many more jellies had trouble getting around once on the planet, including pulsing and movement abnormalities, compared to their Earth-bound counterparts.
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Scientists have a working theory on how life may have come to Earth via an asteroid. But how did life get onto an asteroid in the first place? Several theories exist, but they’re all a little bit different. Scientists at Rensselaer Polytechnic Institute, however, have come up with a new theory that could properly explain how organic material forms on an asteroid.
The theories most often taught in astrobiology revolve around the idea that the asteroids were once warm enough that they could sustain liquid water, which is necessary for organic molecules to form. The space where they originated in is cold, so how did they get heated up to the right temperature? One theory states that the asteroids were heated radioactively, similar to Earth’s interior. The other popular theory involves how plasma interacts with a magnetic field. However, both of these theories are based on the assumption that the asteroid belt between Jupiter and Mars was once warm enough to do do this. Unfortunately, these theories don’t work because the sun was much dimmer back then than originally thought, meaning that the area was even colder than it is now.
The Rensselaer scientists started by looking at the theory involving magnetic fields. That theory states that an asteroid creates an electric field when it moves through a magnetic field. This heats up the asteroid. This theory makes the assumption that a strong solar wind was present, but that has been disproved.
However, starting with this theory gave them something to work with. They used a new understanding of how the process works, and re-calculated the electric field. With that, they determined that something called multi-fluid magneto-hydrodynamics was also at work on the asteroids. This regards how plasma interacts when introduced to a magnetic field. Generally speaking, the plasma’s neutral particles rub up against other particles and create friction. This friction creates heat. This heat creates the correct temperature for organic molecules to form.
Although the scientists feel that this theory is a good one, they still believe there are more questions to be asked and answered regarding the origin of life on asteroids.
Big Bang was mirage from collapsing higher-dimensional star, theorists propose.
It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole — a scenario that would help to explain why the cosmos seems to be so uniform in all directions.
The standard Big Bang model tells us that the Universe exploded out of an infinitely dense point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment.
“For all physicists know, dragons could have come flying out of the singularity,” says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.
It is also difficult to explain how a violent Big Bang would have left behind a Universe that has an almost completely uniform temperature, because there does not seem to have been enough time since the birth of the cosmos for it to have reached temperature equilibrium.
To most cosmologists, the most plausible explanation for that uniformity is that, soon after the beginning of time, some unknown form of energy made the young Universe inflate at a rate that was faster than the speed of light. That way, a small patch with roughly uniform temperature would have stretched into the vast cosmos we see today. But Afshordi notes that “the Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on”.
An international team led by astronomers from Kyoto University, the University of Tokyo and the University of Oxford has released its first version of a 3D map of the Universe from its FastSound project (Note 1), which is surveying galaxies in the Universe over nine billion light years away. Using the Subaru Telescope’s new Fiber Multi-Object Spectrograph, the team’s 3D map includes 1,100 galaxies and shows the large-scale structure of the Universe nine billion years ago.
he FastSound Project, one of Subaru Telescope’s Strategic Programs, began its observations in March 2012 and will continue them into the spring of 2014. Although surveys with 3D maps of the Universe have been conducted on the nearby Universe (e.g., the Sloan Digital Sky Survey with coverage up to five billion light years away), the FastSound project distinguishes itself by developing a 3D map of the far-distant Universe, covering the largest volume of the Universe farther than ten billion light years away. Subaru Telescope’s FMOS facilitates the project’s goal of surveying a large portion of the sky. FMOS is a powerful wide-field spectroscopy system that enables near-infrared spectroscopy of over 100 objects at a time; the spectrograph’s location at prime focus allows an exceptionally wide field of view when combined with the light collecting power of the 8.2 m primary mirror of the telescope.
The current 3D map of 1,100 galaxies shows the large-scale structure of the Universe nine billion years ago, spanning 600 million light years along the angular direction and two billion light years in the radial direction. The team will eventually survey a region totaling about 30 square degrees in the sky and then measure precise distances to about 5000 galaxies that are more than ten billion light years away. Although the clustering of galaxies is not as strong as that of the present-day Universe, gravitational interaction will eventually result in clustering that grows to the current level.
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NASA has been working with Tethers Unlimited to develop SpiderFab, a robotic 3D printing and assembly system that could fabricate components in space. The NASA Innovative Advanced Concepts (NIAC) program recently awarded Tethers Unlimited $500,000 to continue developing the technologies.
SpiderFab adapts additive manufacturing techniques such as 3D printing and robotic assembly technologies to enable space systems to fabricate and integrate large components such as antennas, solar arrays, sensor masts, and shrouds in orbit.
Spacecraft components are currently built on the ground, which is expensive and limits their size. Dr. Rob Hoyt, Tethers Unlimited’s CEO and chief scientist, said:
On orbit fabrication allows the material for these critical components to be launched in a very compact and durable form, such as spools of fiber or blocks of polymer, so they can fit into a smaller, less expensive launch vehicle. Once on orbit, the SpiderFab robotic fabrication systems will process the material to create extremely large structures that are optimized for the space environment. This radically different approach to building space systems will enable us to create antennas and arrays that are tens to hundreds of times larger than are possible now, providing higher power, higher bandwidth, higher resolution, and higher sensitivity for a wide range of space missions.
Strange particles called neutrinos have a habit of switching identities, changing from one flavor into another — a transformation that may help probe some of the fundamental mysteries of the universe.
Now researchers conducting an underground particle detector experiment in China have published their latest measurements of this shape-shifting, which is called neutrino oscillation, and report the most precise values known for certain parameters describing how it occurs.
Neutrinos come in three flavors — electron, muon and tau — which each exist as a mixture of three possible neutrino masses (though the actual value of these masses is currently unknown). Neutrinos may start as one flavor, say electron neutrinos, and then switch into muon or tau neutrinos as they travel through space.
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Particles’ changing masses could explain why distant galaxies appear to be rushing away.
It started with a bang, and has been expanding ever since. For nearly a century, this has been the standard view of the Universe. Now one cosmologist is proposing a radically different interpretation of events — in which the Universe is not expanding at all.
In a paper posted on the arXiv preprint server, Christof Wetterich, a theoretical physicist at the University of Heidelberg in Germany, has devised a different cosmology in which the Universe is not expanding but the mass of everything has been increasing. Such an interpretation could help physicists to understand problematic issues such as the so-called singularity present at the Big Bang, he says.
Although the paper has yet to be peer-reviewed, none of the experts contacted by Nature dismissed it as obviously wrong, and some of them found the idea worth pursuing. “I think it’s fascinating to explore this alternative representation,” says Hongsheng Zhao, a cosmologist at the University of St Andrews, UK. “His treatment seems rigorous enough to be entertained.”
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OUR home galaxy has been weighed, and it is surprisingly lean. The latest gauge of the dark matter mass of the Milky Way suggests it weighs only a quarter to a third of the amount previously estimated.
This could explain the dearth of smaller galaxies buzzing around the Milky Way. But it also means we may live in a cosmic anomaly.
It is thought the first galaxies were born as normal matter coalesced around globs of dark matter, the invisible stuff thought to make up about 80 per cent of the matter in the universe. We can’t see dark matter itself, but we can trace its effects in the motions of stars in modern galaxies.
Stars on the edges of large spirals like the Milky Way are orbiting so fast that they should fly off, so something must be holding on to them. That thing is thought to be a halo of dark matter encircling the visible disc.
Knowing our galaxy’s total mass will tell us a lot about it. “Is our Milky Way typical, or is it actually quite weird?” asks Alis Deason of the University of California, Santa Cruz.
A smattering of stars live in the Milky Way’s dark matter halo, and previous studies have used their motion to figure out the halo’s mass. But we are embedded in a spiral arm, which means dust and gas blocks much of our view of our relatively flat galaxy, so those models had to make assumptions about the parts we can’t see.
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More than 100,000 people are eager to make themselves at home on another planet. They’ve applied for a one-way trip to Mars, hoping to be chosen to spend the rest of their lives on uncharted territory, according to an organization planning the manned missions.
The Mars One project wants to colonize the red planet, beginning in 2022. There are financial and practical questions about this venture that haven’t been clarified. Will there be enough money? Will people really be able to survive on Mars? But these haven’t stopped some 30,000 Americans from signing up.
You can see some of the candidates on the project’s website, but they’re not the only ones who have applied, said Bas Lansdorp, Mars One CEO and co-founder.
“There is also a very large number of people who are still working on their profile, so either they have decided not to pay the application fee, or they are still making their video or they’re still filling out the questionnaire or their resume. So the people that you can see online are only the ones that have finished and who have set their profiles as public,” Lansdorp said.
The entrepreneur did not specify how many have paid the fees, completed their profiles and configured them as private.
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The whole of the sun’s magnetic field is about to “flip”, according to NASA - with warning signs being spotted by observatories around the world this year.
This “flip” happens every 11 years, and coincides with the greatest solar activity in the “cycles” of the sun, known as “Solar Maximum” – with sunspots and “coronal mass ejections” on the surface of the sun.
“It looks like we’re no more than 3 to 4 months away from a complete field reversal,” says solar physicist Todd Hoeksema of Stanford University. “This change will have ripple effects throughout the solar system.”
The effects are so powerful they will be felt beyond Pluto – and may affect phenomena such as cosmic rays, which some believe can alter the climate on Earth.
Scientists have recorded these “flips” for decades, but the process is still not fully understood. This particular “flip” has already puzzled scientists – with one magnetic pole of the sun appearing to flip “too early” last year.
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