NASA: Space centaurs are likely comets

A mystery is solved. Or is it?


Photo credit:

Science Recorder | Drew Adams | Friday, July 26, 2013



Centaurs, small solar system bodies that orbit the sun between Jupiter and Neptune, have long been considered one of the more mysterious cosmic bodies in observable space. Astronomers questioned whether or not the bright objects are asteroids or comets, but a new study released online with the Astrophysical Journal supposes that it finally has the answer.

The name “centaur” was given to the objects due to the duality of their comet/asteroid characteristics, not unlike the dual horse/man dichotomy of the mythical beast. That’s where the similarities stop, however, and even the basic duality of cosmic centaurs may no longer hold applicable now that data from NASA’s Wide-field Infrared Survey Explorer, or WISE, has gathered strong evidence that they are in fact comets.

“Just like the mythical creatures, the centaur objects seem to have a double life,” said James Bauer in a statement from NASA’s Jet Propulsion Laboratory. “Our data point to a cometary origin for most of the objects, suggesting they are coming from deeper out in the solar system.”

Bauer is the lead author of the new study on centaurs, which appeared online on July 22. The phrase “cometary origin” addresses the fact that centaurs might have been active comets in the past or could be active again in the future. These qualities are partly how comets are differentiated from asteroids, which originate from the inner solar system.

The new data from WISE highlights further differences between comets and asteroids and favors centaurs as examples of the former. NEOWISE, the segment of the WISE program dedicated to locating asteroids, performed the largest infrared survey of centaurs and a number of scattered disk objects. It located 52 objects in all, 15 of which are new discoveries.

A study of the bodies’ albedos, or the ratio of light reflected by a cosmic object to that received by it, compared new information of the centaurs’ color to what has been collected in the past. Visible-light data has pegged centaurs as either blue/gray in color or having a red hue. While blue/gray objects can be either comets or asteroids, dark blue/gray objects are typically comets. Reddish objects are usually considered to be asteroids.

Tommy Grav, researcher with the Planetary Science Institute in Tucson, AZ, and co-author of the study, said that comets have surfaces like charcoal and that asteroids are shiny, much like the moon. Two-thirds of the centaurs observed had coloration that was indicative of a comet. It remains unclear if the final third is made up of comets or asteroids.

“That means the small body populations found beyond the Main Asteroid Belt, like the Hildas, Jupiter Trojans and Centaurs, were either formed where they currently are, or they were inbound objects coming from the far reaches of the Solar System that settled into their current orbits,” said Grav in a press release.

For now, NEOWISE will continue to study the centaurs for more information.



Read more: http://www.sciencerecorder.com/news/nasa-space-centaurs-are-likely-comets/#ixzz2a9mMGQrQ

How Earth Accelerates Electrons to 99.9 Percent of Light Speed

Earth's Van Allen belts (not to be confused with the astrophysical hard-rock 'Van Halen' phenomenon) rocket electrons around the Earth at near light speed. One scientist just figured out how it's done.

By William Herkewitz



Energy from the dynamic sun drives a complex chain of processes in the Earth's magnetosphere that ultimately lead to strong intensifications of the radiation belts.
Geoff Reeves, Los Alamos National Laboratory

July 25, 2013 2:00

As the Sun's churning surface lets loose a belch of white-hot flame, it sends out a storm of radiation that washes over the solar system. Luckily for us, Earth's magnetic field shields us from most of these deadly rays. But overhead, something strange and lethal is happening when the solar wind bombards the Earth. A band of radioactive particles circling the planet, called the outer Van Allen belt, starts to charge up like a rail gun. It whips electrons along on its circular racetrack at a breakneck pace—near light speed. The powerful band ebbs and flows with solar radiation, but until today, nobody could be sure how it was creating such swift and energetic particles.

"This is like watching a natural particle accelerator in space," says Geoffrey Reeves, a magnetic field researcher at Los Alamos National Laboratory.

Reeves and a team of scientists published research today in the journal Science describing the bizarre way the outer Van Allen belt—which orbits around the Earth like a giant doughnut—accelerates electrons to more than 99.9 percent of the speed of light. Discounting light itself, Reeves says, "these electrons are the fastest things the Earth creates naturally." And they aren't simply a high-velocity curiosity: They pose a threat to the International Space Station and to commercial satellites. The particles can burst through the protective shielding—causing temporary computer failures—and cause degradation to vital onboard equipment such as solar panels.


Surfing Radio Waves
Reeves and his team, with the help of a pair of newly launched NASA satellites called the Van Allen Probes, showed that the electrons in the belt gain their breathtaking velocity by hitching rides on radio waves. Daniel Baker, an astrophysicist with the study from the University of Colorado at Boulder, says that as solar radiation crushes against the Earth's magnetic field, a surge of radio and other waves begin to pump through the Van Allen belts. By chance, some of the radio waves are the exact frequency as electrons already twirling through the belt at slow speeds. "So the electrons hitch a ride—sort of surfing on these waves—and can be carried to these high speeds," Baker says. "It's a subtle but very powerful interaction."



Reeves says the new NASA satellites, launched last August, are the main reason researchers ID'd this radio wave surfing. "We had the right instruments, the satellites were in the right orbit, and we had two of them," he says. Previous satellites used to measure the Van Allen belts lacked the tools or orbit to take successive measurements deep within the hazardous core of the belts. They could get a snapshot, but not a moving picture, of how the Van Allen belts evolve and respond to solar wind. The heavily shielded Van Allen probes repeatedly darted through the heart of the Van Allen belt, quickly measuring the entire range of slow to speedy electrons.

Knowing how Earth's natural electron accelerator works is important for more reasons than just satisfying scientific curiosity. Because of the Van Allen belts' doughnut-like shape and constant expansion and contraction with solar wind, their high-energy electrons can impact almost every satellite in orbit. "It's a rare satellite that isn't affected by this," Baker says, "and we have numerous examples through the last couple of decades where we've seen absolutely confirmed evidence that this is a serious operational problem."

Still, Jean-Luc Froeliger, the vice president of satellite engineering at Intelsat, which operates the world's largest commercial satellite fleet, cautions that while the Van Allen belts' high energy particles can do long-term damage to satellites, all modern satellites are built to withstand this particle barrage with extra shielding covering vital components, and major damage is rare. "I don't know any commercial satellite that has been totally destroyed by high energy elections," Froeliger says, "but there is certainly an impact, in that the solar arrays degrade the more a satellite's bombarded by particles."


Forecasting Space Storms
The researchers hope that by understanding the Van Allen belt, they can predict when it will be at its worst, and develop methods to keep our satellites better protected. Figuring out how the electrons accelerate is the first step. "If we want to be able to predict when the radiation belts are going to get very intense, we have to know what's the source of the energy," Reeves says.

The Van Allen belts are still by no means fully understood. Vassilis Angelopoulos, a magnetic field expert at the University of California, Los Angeles, who was not involved in the study, points out that while we've discovered how the electrons are accelerated, we still don't know how solar radiation creates these surfable radio waves. "What generates the waves to begin with still remains to be solved," Angelopoulos says. "While we're putting to rest one of the important questions about the Earth's [radioactive belts], there is still a lot of work to be done to reach a predictive capability within our models."

Reeves argues that in a world increasingly reliant on all the technologies satellites foster—from GPS to telecommunications—working to protect satellites is an essential goal. "Even when you swipe your credit card at the gas station," he says, "that transaction will go through a satellite before it goes to your bank."



Read more: How Earth Accelerates Electrons to 99.9 Percent of Light Speed - Popular Mechanics

UK team designs human mission to Mars

24 July 2013 Last updated at 06:54 GMT

By Neil Bowdler

Science and health reporter, BBC News


A team of scientists from Imperial College London discuss how we could put a human on Mars


Scientists at Imperial College London have designed a concept mission to land astronauts on Mars.

The plan envisages a three-person crew journeying to Mars aboard a small two-part craft.

The craft would rotate to generate artificial gravity and use a heat shield to protect itself against solar flares.

The crew would then return to Martian orbit in a pre-sent craft fuelled using ice from beneath the planet's surface.

The concept, developed in conjunction with the BBC, is intended to spark further debate about the technical obstacles and risks that would have to be overcome in order to put humans on Mars.

How to put a human on Mars

Click to visit interactive site

"Every part of this mission scenario has been demonstrated one way or the other, including the in situ propellant production on the surface of Mars," said Prof Tom Pike, who led the Imperial design team.

"There are big, big jumps between a demonstration at one level and putting together the engineering systems for a mission, but they are engineering challenges. They are not fundamentally about making new discoveries."

The new Imperial concept comes amid renewed interest in the Red Planet with two private groups having proposed missions in recent months.

The Imperial team have designed a two-part craft, consisting of a Martian lander with a heat shield, inside which the crew would also ascend into Earth orbit.

Directly beneath the lander on the launch pad would be a "cruise habitat vehicle", a cylindrical craft split into three floors and measuring some 10m (30ft) in height and 4m in diameter.

Once in Earth orbit, the astronauts would move from the lander into the larger habitat vehicle before a rocket burst would propel the conjoined craft on a trajectory to Mars. The quickest journey time would be nine months when Earth and Mars are in optimum alignment.


Shortly into the journey, the lander and cruise vehicle would unwind from each other on a steel cable tether to a distance of some 60m. Short thruster bursts from both vehicles would then set them spinning around a centre of gravity.

This would create artificial gravity within the habitat vehicle similar to Earth's gravity, which the scientists believe would prevent the type of muscle and bone wastage that weightlessness would cause, which would render the astronauts unable to walk on Mars once they arrived.

Later in the mission, the spin rate could be reduced to better emulate Martian conditions, where gravity is 40% that on Earth.

"We've obviously got some real issues with a long-term mission in terms of the de-conditioning which goes on in the space environment," Ryan Robinson, the Imperial team's physiologist, told BBC News.

"Bones loss [in a weightless environment] is about 1-2% a month and if they're landing they'll be susceptible to fractures if they've got to be exerting themselves."

During the journey, the crew's health would be monitored closely with wireless sensors - but they would rely entirely on medication aboard the craft and the skills of their fellow crew members should they fall sick.



A crew would face cosmic and solar radiation en route and on Mars

The long journey and confined quarters could also affect their mental health, and conflicts between the crew could arise.

During the journey, the craft could deploy a number of measures to try to reduce the threat to the astronauts from solar and cosmic radiation, the former from the Sun, the later emanating from beyond our solar system.

Water could run within the shell of the cruise craft to absorb radiation, while the Imperial team also examined the idea of fitting superconducting magnets to the craft, which would generate a magnetosphere to deflect solar and cosmic radiation in the way the Earth's natural magnetosphere does.

The crew would also deploy emergency procedures should satellites detect a major incoming solar flare.

This would involve winding in the tether and re-directing the lander's heat shield towards the Sun to protect the astronauts in the cruise craft.

The crew would also put whatever they could find between them and the front of the vehicle to absorb the solar burst.



Artificial gravity is proposed for the craft to prevent muscle and bone loss on the journey to Mars

Even with such measures, a solar flare could still kill, or result in cancers. Cosmic radiation could also take its toll.

"We've got some great results from the Mars curiosity rover," said Imperial's Martin Archer, who specialises in solar and cosmic radiation.

"On its trip to Mars, it measured the radiation from these galactic cosmic rays and it was exposed to quite a lot - about two-thirds of the level that Nasa is prepared to risk over the whole of an astronaut's life, just on the way there and back again."

Once the craft reaches Martian orbit, it would contract together and the astronauts would pass into the lander ready for detachment and descent.

Its shield would absorb the heat of entry before being jettisoned and then multiple parachutes would deploy to slow the craft, with thrusters used to further slow and guide it through the final metres to the landing site.

The Imperial team propose a landing site near the equator, where milder conditions exist.

They would hope to land near a pre-sent Martian habitat module and rover, although the rover could be robotically controlled to travel from the habitat to the landing site if the distance was too great for a crossing on foot.

Then the Martian visit would begin - a first human landing on another planet.


The time spent on the Martian surface would be dictated by the next time Earth and Mars aligned for a speedy return home. It could be two months, or we might choose to spend more than two years on Mars, says the Imperial team.

It is during this time that the human crew could try to demonstrate why humans could still outperform robots in analysing and understanding the Martian environment.

"Some people think that the use of humans is just something that is popular and attractive from an adventure and inspirational point of view, but there are also real scientific benefits for sending humans," said Prof Mark Sephton, the team's geologist.

"Humans can data process while they're walking around, while they're looking at rocks. They're probably the most sophisticated computer, the most sophisticated robotic living organism that we can imagine."

Radiation would remain a danger during the stay, with Mars possessing no magnetosphere to shield the surface from cosmic and solar rays. Shovelling up soil from the surface during the mission and part-burying the habitat module could help, as could staying inside during a solar burst.

Then comes the return home, which would be far from simple.

The approach taken by the Imperial scientists would be to pre-send both the habitat module, rover and a return vehicle before any human launch.

The return vehicle would land at a latitude where water ice would be found in large amounts just a few centimetres beneath the surface. Robotic devices would mine the ice, which would then be split into hydrogen and oxygen using electrolysis.

These gases could be used as fuels on their own, or the hydrogen could be combined with carbon dioxide from the Martian atmosphere using a catalyst to produce methane, which is a more stable and energy-dense fuel than hydrogen.



The team suggest we could mine Mars for ice to fuel the return craft

As the Imperial team propose landing near the equator, a crew would have to travel by rover to a cooler latitude where the return vehicle and ice-mining devices would be waiting. Several hundreds of kilometres may have to be crossed, posing both risks and opportunities to further explore the Martian landscape.

Should they make it safely, the crew would have a narrow launch window to ensure the quickest most fuel-efficient return to Earth.

After leaving Mars, the return vehicle would dock with the orbiting cruise vehicle and replace the Martian lander as the counter-balance within the spinning tethered structure en route to Earth. Like the lander, the return vehicle would have to be fitted with a shield to protect the crew during extreme solar activity.

After at least nine months, the craft would reach Earth orbit and dock with the International Space Station before the astronauts could take a Soyuz capsule home, the team envisages.

The new Imperial concept comes amid renewed interest in the Red Planet, with two private groups having proposed missions.

Businessman and former space tourist Dennis Tito wants to send an American couple on a mission beginning in 2018 that would pass within 100 miles (160km) of Mars before using the planet's gravity to "slingshot" the craft back to Earth.

The Dutch project Mars One proposes putting a human colony on the planet beginning in 2023, while SpaceX chief executive Elon Musk has spoken of sending a private human mission to Mars within 12-15 years.

The US, Russian, European and Chinese space agencies maintain long-term plans to put humans on Mars.

From: http://www.bbc.co.uk/news/science-environment-22952441

Scientists find strange, shape-shifting particles

By Clara MoskowitzPublished July 23, 2013
LiveScience




A candidate electron neutrino appears in the Super Kamiokande particle detector in Japan like this. In July 2013 researchers announced they'd definitively measured muon neutrinos oscillating flavor into electron neutrinos. (T2K)


Exotic particles called neutrinos have been caught in the act of shape-shifting, switching from one flavor to another, in a discovery that could help solve the mystery of antimatter.

Neutrinos come in three flavors: electron, muon and tau and have been known to change, or oscillate, between certain flavors. Now, for the first time, scientists can definitively say they've discovered muon neutrinos changing into electron neutrinos.

The discovery was made at the T2K neutrino experiment in Japan, where scientists sent a beam of muon neutrinos from the J-PARC laboratory in Tokai Village on the eastern coast of Japan, streaming 183 miles away to the Super-Kamiokande neutrino detector in the mountains of Japan's northwest.

The researchers detected an average of 22.5 electron neutrinos in the beam that reached the Super-Kamiokande detector, suggesting a certain portion of the the muon neutrinos had oscillated into electron neutrinos; if no oscillation had occurred, the researchers should have detected just 6.4 electron neutrinos.[Wacky Physics: The Coolest Little Particles In Nature]



'[It] may lead us to understand why there is so much more matter than antimatter in the universe. The neutrino may be the very reason we are here.'
- physicist Alfons Weber of the U.K.'s Science and Technology Facilities Council



In 2011, T2K scientists announced they'd seen indications that this shape-shifting was taking place, but they couldn't say with certainty that the effect wasn't one of chance. The experiment has now collected enough data for the researchers to say the probability of this effect being produced by random statistical fluctuations is less than one in a trillion.The results were announced Friday (July 19) at the European Physical Society meeting in Stockholm.

The discovery opens an intriguing avenue for studying antimatter, the strange cousin of matter that's mysteriously missing in the universe. Scientists think the Big Bang produced about as much matter as antimatter, but most of this antimatter was destroyed in collisions with matter, leaving a slight excess of matter to make up the universe we see today.

The best shot at explaining why matter won out in this cosmic struggle is to find instances where a matter particle behaves differently than its antimatter counterpart. Many physicists suspect that neutrino oscillations might be just the type of occasion to see this difference.

Now that the researchers have observed this oscillation pattern in neutrinos, they can recreate the experiment with a beam of anti-muon neutrinos, and find out whether they change more or less often into anti-electron neutrinos.

"Our findings now open the possibility to study this process for neutrinos and their antimatter partners, the anti-neutrinos," physicist Alfons Weber of the U.K.'s Science and Technology Facilities Council and the University of Oxford, said in a statement. "A difference in the rate of electron or anti-electron neutrino being produced may lead us to understand why there is so much more matter than antimatter in the universe. The neutrino may be the very reason we are here."

This next phase of the project will likely take at least a decade, the researchers said.

"We have seen a new way for neutrinos to change, and now we have to find out if neutrinos and anti-neutrinos do it the same way," T2K team member Dave Wark of the Science and Technology Facilities Council said in a statement. "If they don't, it may be a clue to help solve the mystery of where the matter in the universe came from in the first place. Surely answering that is worth a couple of decades of work!"


Read more: http://www.foxnews.com/science/2013/07/23/strange-particles-shape-shift-from-one-flavor-to-another/#ixzz2Zxx80qKG

Dolphins 'call each other by name'By Rebecca MorelleScience reporter, BBC World Service

The research sheds new light on the intelligence of dolphins


Scientists have found further evidence that dolphins call each other by "name".

Research has revealed that the marine mammals use a unique whistle to identify each other.

A team from the University of St Andrews in Scotland found that when the animals hear their own call played back to them, they respond.

The study is published in the Proceedings of the National Academy of Sciences.

Dr Vincent Janik, from the university's Sea Mammal Research Unit, said: "(Dolphins) live in this three-dimensional environment, offshore without any kind of landmarks and they need to stay together as a group.

"These animals live in an environment where they need a very efficient system to stay in touch."

Signature whistles

It had been-long suspected that dolphins use distinctive whistles in much the same way that humans use names.

Previous research found that these calls were used frequently, and dolphins in the same groups were able to learn and copy the unusual sounds.

But this is the first time that the animals response to being addressed by their "name" has been studied.

“Most of the time they can't see each other, they can't use smell underwater... and they also don't tend to hang out in one spot”

Dr Vincent Janik

University of St Andrews


To investigate, researchers recorded a group of wild bottlenose dolphins, capturing each animal's signature sound.

They then played these calls back using underwater speakers.

"We played signature whistles of animals in the group, we also played other whistles in their repertoire and then signature whistles of different populations - animals they had never seen in their lives," explained Dr Janik.

The researchers found that individuals only responded to their own calls, by sounding their whistle back.

The team believes the dolphins are acting like humans: when they hear their name, they answer.

Dr Janik said this skill probably came about to help the animals to stick together in a group in their vast underwater habitat.

He said: "Most of the time they can't see each other, they can't use smell underwater, which is a very important sense in mammals for recognition, and they also don't tend to hang out in one spot, so they don't have nests or burrows that they return to."

The researchers believe this is the first time this has been seen in an animal, although other studies have suggested some species of parrot may use sounds to label others in their group.

Dr Janik said that understanding how this skill evolved in parallel in very different groups of animals could tell us more about how communication developed in humans.

From: http://www.bbc.co.uk/news/science-environment-23410137

Powerful Atlas 5 lifts massive Navy satellite into orbit

BY JUSTIN RAY
SPACEFLIGHT NOW
Posted: July 19, 2013


Leaping off the launch pad Friday in its most powerful arrangement to boost its heaviest payload into orbit, a United Launch Alliance Atlas 5 rocket successfully deployed the second in a series of sophisticated spacecraft to grow the U.S. Navy's new mobile communications network that will span the globe.



Credit: Walter Scriptunas / Spaceflight Now
See more launch photos


The energetic rocket, created by attaching five strap-on solid-fuel motors to the kerosene-fed main stage to deliver two-and-a-half million pounds of thrust, launched from Cape Canaveral at 9:00 a.m. EDT.



The 206-foot-tall rocket blasted off after its overnight countdown progressed smoothly and a brief hold for upper level wind conditions to clear.

It begins a string of five national security launches that the Air Force will perform with United Launch Alliance in a three-month span through October, using both Atlas and Delta 4 rockets from the Cape and Vandenberg Air Force in California. The future flights will deploy two Air Force communications spacecraft, a massive spy satellite for the National Reconnaissance Office and a new GPS bird.

The surge began in successful fashion with the Navy's Mobile User Objective System satellite No. 2, taking the next step to construct a worldwide communications system using 3G-cellular technology for ships, submarines, aircraft, land vehicles and terminals in the hands of troops.

"When the constellation is fully populated, users will be able to speak to any other user on the globe," said Navy Capt. Paul Ghyzel, manager of the Satellite Communications Program Office.



Credit: Walter Scriptunas / Spaceflight NowSee more launch photos


"Today, the traditional (satellite communications) system, two users who want to communicate with each other need to be underneath the same satellite. MUOS changes that.



"So with the second satellite being launched and checked out and put into operations, we'll continue our coverage (expansion) of the globe and basically double it because we will have two satellites on-orbit working towards our ultimate objective of true global coverage once we get the remaining satellites on-orbit. That's really the big coverage gain (with Friday's launch).

"From a technical standpoint, with two satellites on-orbit it allows us to verify and validate how the system works. As we test out the system, we'll be communicating with a user that's underneath satellite No. 1, the traffic, both voice and data traffic will be routed through the ground network and routed up through the second satellite in several of our test scenarios to be sent to a user or multiple users that are underneath the footprint of the second satellite."

MUOS 1 was launched in February 2012 and put into operation by year's end. MUOS 2 will complete its post-launch orbit shaping in about 8 days, then deploy its solar arrays and twin umbrella-like antenna reflectors to achieve the "flight configuration" about 12 days after launch.

Then begins several months of satellite system and payload testing before builder Lockheed Martin hands over the craft to the government for additional checks in advance of setting it operational in early 2014.

From its eventual spot in geosynchronous orbit, a parking spot 22,300 miles up, the expansive footprint of MUOS 2 will cover nearly a third of the planet. However, what geographical area of the globe the craft will cover hasn't been finalized yet, officials said.

MUOS serves a dual-provider of both voice traffic currently routed by the Navy's existing generation, albeit aging, Ultra High Frequency Follow-On spacecraft, but it also creates a new era of mobile communications built around 3G cellular technology to relay narrowband tactical information such as calls, data messaging, file transfers and email on rates of up to 384 Kilobits per second.



An artist's concept of MUOS. Credit: Lockheed Martin


"One of the way we frequently describe the new capabilities that MUOS brings is think of a cellphone," Ghyzel said.



"The architecture that we've built with the satellite constellation and with the global ground network, the satellite is the celltower. Anybody that is using a radio that is capable of communicating with MUOS, when they speak their transmission is picked up by the satellite and then routed like a cellular system would route to wherever it needs to be to talk to the guy on the other end.

"So if you are driving down the interstate and you walk to talk to a guy one county over, you may be using the same tower. For Bob to talk to Jim.

"But if Bob is in Florida and wants to talk to his wife in Seattle, he can pick up a cellphone, the tower next to the interstate he is driving on is going to pick up that call, but then it is going to go through a fiber optic network to get to a celltower that is closest to his wife in Seattle and that tower is going to send that call to her cellphone.

"Much like for us in MUOS, if you got somebody that's in Hawaii that needs to talk to a ship that's 200 miles off Hawaii, that traffic is going to go through the satellite that is over the Pacific.

"But if that ship commander needs to talk to somebody that is in Afghanistan, then they are going to transmit over MUOS, the satellite over the Pacific is going to up that transmission, but (it is) then routed through the rest of the MUOS network to the satellite that's going to be over the Indian Ocean, eventually, and then down into Afghanistan.

"You can think of the satellites as the celltowers in the sky. That's a really good way to think of how the system works."

MUOS 3 is expected to launch in about 12 months, followed by MUOS 4 in the summer of 2015. The constellation will feature four primary satellites and one on-orbit spare, all designed and built as clones of each other.

From: http://www.spaceflightnow.com/atlas/av040/#.UevctJObe3I

Origin of gold found in rare neutron-star collisions

Posted: Sunday, July 21, 2013 8:00 am

By Joel Achenbach The Washington Post



Gold, the most widely beloved of the precious metals, might have its origin in extremely rare and violent explosions in the far reaches of outer space. The bling apparently begins with a blam.

For many years, scientists had theorized that the heavy elements of the periodic table, such as gold, platinum, lead and uranium, had their origin in supernova explosions. But the source, scientists have announced, might be even more exotic: the collision of two ultra-dense objects called neutron stars.

The elements on Earth are all of cosmic origin. Carbon and oxygen atoms in our bodies, for example, come from the interior of stars, where they were formed under high pressure and heat. They were later spewed into the universe in supernova explosions. But what hasn’t been known is whether these supernova events could account for the heaviest of the elements. A heavy element such as gold has 79 protons, 79 electrons and 118 neutrons. That’s a lot of mass for one atom. Most of the elements are simpler; gold and the other heavy elements are cosmically extravagant.

The neutron stars might provide the explanation.

Neutron stars are the collapsed cores of stars that have exploded in a supernova. A neutron star might be roughly the diameter of Washington but contain as much mass as our sun, all of it crammed together by the force of gravity, until even the atoms have collapsed, leaving the object with the density of an atomic nucleus.

Most of these cosmic fruitcakes are solitary wanderers, but some are paired up, as remnants of binary stars. They will orbit a common point in space and gradually drift closer and closer. One day, they will collide.

Astronomers are fortunate in that the universe is so vast, containing many billions of galaxies, that any all-sky survey might possibly see something even as rare as a neutron-star collision. So it was that on June 3, NASA’s Swift space telescope observed a flash of light, called a short gamma-ray burst (GRB), in an extremely distant galaxy in the constellation Leo.

Astronomers scrambled to reobserve that tiny patch of space with a powerful telescope in Chile and with the Hubble Space Telescope.

They saw something glowing where they’d earlier seen the GRB. After comparing their observations with theoretical models, the astronomers concluded that they were seeing the radioactive afterglow from a huge quantity of heavy metals formed by a neutron-star smashup.

This observation potentially explains this type of short-duration GRB. These flashes of light can briefly outshine an entire galaxy.

“When they make contact, several exciting things happen very quickly,” said Edo Berger, an astronomer who led the research at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. Berger said. “Most of the material actually collapses to form a black hole. Some of the material then gets sucked into the black hole. That is the event that causes the gamma-ray burst. Some of the material gets spewed out into space. That material, since it came from neutron stars, is very rich in neutrons, and is very efficient at forming these heavy elements, including gold.”

Berger said the neutron-star collisions produce essentially everything up and down the periodic table.

The gold is basically dust in the wind, atomized, until it winds up in a cloud of material that can coalesce, through the force of gravity, into a solar system of planets with a star at the center.

Then the gold atoms have to find one another and become concentrated.

From: http://www.sentinelsource.com/features/technology/origin-of-gold-found-in-rare-neutron-star-collisions/article_d43d48c5-eacd-5a5f-aac3-fbd144f4c033.html

Is sending humans to Mars actually feasible?

"The challenge ahead is epic, but historic," says Buzz Aldrin. "We are on a pathway to homestead the Red Planet."
By The Week Staff | 10:00am EST


The next hot location for homesteaders                                      NASA/Pat Rawlings/SAIC

Why go to Mars?

The idea of a manned journey to Mars has animated science fiction for more than a century, and since the dawn of the space age, plans have been proposed for how it might be done. But for decades, any real momentum toward that dream seemed lost. In 1989, a plan advanced by President George H.W. Bush to send a manned mission to the Red Planet was shelved when its costs were estimated at more than $500 billion. In recent years, however, the prospects of a Martian voyage have been looking up. In 2010, the Obama administration called on NASA to set "far-reaching exploration milestones," including sending astronauts to Mars by the mid-2030s. But NASA still has no budget for a manned mission, let alone the technology to land humans there safely and then bring them back. Several commercial spaceflight companies are working on plans to send people to Mars in about a decade. Former astronaut Buzz Aldrin believes it's possible. "The challenge ahead is epic, but historic," he says. "We are on a pathway to homestead the Red Planet."

What would such a mission take?

Just getting humans to Mars would require new solutions to some stiff challenges. At the closest points of their orbits, Earth and Mars are 34 million miles apart, and astro-engineers figure it would take a manned spacecraft five to 10 months to reach Mars. That is a long time for astronauts to be in interplanetary space, where they'd need much tougher protection against cancer-inducing space radiation than they do in Earth's orbit. A trip to Mars would require vast quantities of equipment, food, and fuel. Some have suggested sending supplies separately to allow astronauts to travel in a lighter — and faster — vessel. But even if a manned mission reached Mars' orbit in good order, landing there safely poses other daunting problems. Mars' atmospheric pressure is less than 1 percent of Earth's, making it difficult to slow a spaceship hurtling toward the surface at an estimated speed of 13,000 miles per hour. Unmanned rovers have cushioned their descents with heat shields, parachutes, and rockets, but current technology is insufficient for landing a much larger manned spacecraft, even if supplies were sent separately. "We're talking about landing perhaps a two-story house, and then another two-story house with fuel and supplies right next to it," said former NASA technologist Bobby Braun. "That's a fantastic challenge."

How far have plans progressed?

NASA teams are working on experimental projects with an eye to a possible mission to Mars and back about 25 years hence. But some in the private sector don't want to wait that long. Multimillionaire space tourist Dennis Tito has hatched a low-budget, $128 million plan to send a 50-ish married couple on a 501-day flyby that would zoom past Mars in 2018 and then use the planet's gravity to slingshot the spacecraft back to Earth. More ambitiously, the Dutch nonprofit Mars One wants to start colonizing Mars within a decade, and has already collected more than 78,000 applications from civilians willing to take a one-way trip to Mars. The group plans to select six teams of four with the necessary "intelligence, resourcefulness, courage, determination, and skill, as well as psychological stability." They would then undergo seven years of training and testing, including time in mock Mars colonies — all to be chronicled in a revenue-yielding Survivor-style television series — to make the final cut.

Would living on Mars be dangerous?

Scientists have serious concerns about the health risks of long-term exposure to radiation, reduced gravity, longer days, and extraterrestrial atmospheric conditions. Astronauts are known to experience bone degradation, muscle loss, and swollen optic nerves from spending too much time in zero gravity. A Russian-sponsored experiment called Mars 500, in which six men were confined for 500 days under conditions meant to emulate a Mars mission, showed that Mars travelers could face severe sleep disturbances, lethargy, and depression. Scientists also worry about the Martian surface's ultra-fine dust, which contains highly chlorinated salts called perchlorates that can cause respiratory problems and thyroid damage. And there's a chance, however slim, that Mars harbors potentially virulent microbes.

What would daily life on Mars be like?

Martian colonists would need a base large enough to contain comfortable, long-term living quarters and a vast array of life-support systems and supplies. They would have to construct their pressurized, air-tight habitat in phases, much the way the International Space Station was built. A secure, long-term food supply would be crucial. One company is working on 3-D printers that would combine powders and concentrates to create foods that replicate the textures, flavors, and smells of natural foods. Eventually, Martian farmers could grow food in pressurized greenhouses, using genetically modified crops to compensate for the planet's high radiation and low sunlight. Volunteers for the commercial missions say that the trade-offs in quality of life would be worth it. "I've had a deep need to explore the universe since I was a kid," said Peter Greaves, a self-employed technologist. "I envision life on Mars to be stunning, frightening, lonely, quite cramped, and busy. But my experience would be so [different] from all 6 to 7 billion human beings. That, by itself, would make up for the factors I left behind."

An insurance policy for human survival

"Single-planet species don't survive," says former astronaut John Grunsfeld. He is among the researchers, astronauts, and space exploration firms who see establishing an outpost on the Red Planet not just as a scientific challenge, but as essential to mankind's survival. Cosmologist Stephen Hawking thinks so, too. "The human race shouldn't have all its eggs in one basket, or on one planet," he says. Should nuclear proliferation, shrinking resources, a growing population, climate change, or a visit by hostile aliens threaten humankind on Earth, a colony on Mars could serve as a lifeboat to keep the species going. "I believe that we will eventually establish self-sustaining colonies on Mars and other bodies in the solar system," Hawking says. But he figures it won't happen "within the next 100 years."

From: http://theweek.com/article/index/247045/is-sending-humans-to-mars-actually-feasible

Evidence for Ancient Ocean on Mars Identfied

By Tamarra Kemsley
Jul 18, 2013 10:34 AM EDT

A possible delta on Mars where a mighty river may have once flowed into a vast ocean has been discovered by researchers at the California Institute of Technology (Caltech). (Photo : NASA)


A possible delta where a mighty river may have once flowed into a vast ocean on Mars has been discovered by researchers at the California Institute of Technology (Caltech).

This ocean, if it existed, could have covered much of Mars' northern hemisphere - stretching over as much as a third of the planet, according to the study published in the Journal of Geophysical Research. At the very least, the researchers say, the water would have covered the entire Aerolis Dorsa region, which spans about 100,000 square kilometers (60,000 square kilometers).

"Scientists have long hypothesized that the northern lowlands of Mars are a dried-up ocean bottom, but no one yet has found the smoking gun," Mike Lamb, an assistant professor of geology at Caltech and a coauthor of the paper, said in a press release.

While the new findings may not be "proof" per se of the existence of an ancient ocean, they provide some of the strongest support yet of one, according Roman DiBiase, a postdoctoral scholar at Caltech and lead author of the paper.

In order to come to their conclusion regarding the delta, the Caltech team used new high-resolution images from the Mars Reconnaissance Orbiter (MRO) to study a 100-square-kilometer area located on the possible former coastline.

Previous satellite images have shown that this area is covered in ridge-like features called inverted channels that form when coarse material, like gravel and cobbles, are carried along a river and deposited at the bottom.

After the river dries up, the finer materials erode away, leaving behind the coarser remains. This sediment then appears as today's ridge-like features, tracing the former river system.

When looked at from above, the inverted channels appear to fan out, a configuration that suggests a number of origins.

First, the channels could have once been a drainage system in which streams and creeks flowed down a mountain and converged to form a larger river.

Second, the water could have flowed in the opposite direction, creating an alluvial fan, in which a single river channel branches into multiple smaller streams and creeks.

Finally, the channels could be part of a delta, which is similar to an alluvial fan except that the smaller streams and creeks empty into a larger body of water.

To figure out which of these scenarios was most plausible, the researchers turned to satellite images taken by the HiRISE camera on the MRO.

By taking pictures from different points in its orbit, the spacecraft was able to make stereo images that allowed the scientists to determine the topography of the Martian surface. Furthermore, the HiRISE camera can pick out features as tiny as 25 centimeters long and the topographic data can distinguish changes in elevation at a resolution of 1 meter.

Using this information, the Caltech researchers analyzed the stratigraphic layers of the inverted channels, piecing together the history of how sediments were deposited along these ancient rivers and streams.

In addition, the team was able to determine the slopes of the channels back when water was still coursing through them, which in turn can reveal the direction of water flow. By doing so, they were able to narrow their options down to an alluvial fan or delta since, in this case, the water was spreading out instead of converging.

Next, the researchers were able to remove alluvial fans from their choices after they found evidence for an abrupt increase in slope of the sedimentary beds near the downstream end of the channels, suggesting that it once emptied into a large body of water.

Thus, the scientists were left with a delta as their most likely answer.

Should this be the case, it would not mark the first time scientists have discovered Martian deltas; however, most are found inside a geological boundary, like a crater. Water therefore would have most likely flowed into a lake enclosed by such a boundary and so did not provide evidence for an ocean.

This new delta, on the other hand, isn't located near any confining boundary, which suggests that the water likely emptied into a large body of water such as an ocean.

"This is probably one of the most convincing pieces of evidence of a delta in an unconfined region - and a delta points to the existence of a large body of water in the northern hemisphere of Mars," DiBiase says.

Other plausible explanations remain, such as a large confining boundary that has since been erased. For this reason, the researchers plan to continue exploring the boundary between the southern highlands and northern lowlands - the hypothetical ocean coastline - and analyze other sedimentary deposits in order to determine if they yield more evidence of an ocean.

"In our work and that of others - including the Curiosity rover - scientists are finding a rich sedimentary record on Mars that is revealing its past environments, which include rain, flowing water, rivers, deltas, and potentially oceans," Lamb says. "Both the ancient environments on Mars and the planet's sedimentary archive of these environments are turning out to be surprisingly Earth-like."

From: http://www.natureworldnews.com/articles/3022/20130718/evidence-ancient-ocean-mars-identfied.htm

Gold on Earth formed in collision of exotic stars

Dan Vergano @dvergano , USA TODAY7:41 p.m. EDT July 17, 2013

There's gold in them thar neutron stars! That's right, astronomers claim Earth's gold, the stuff of wedding bands and pricey speaker wires, originated in cataclysmic collisions of exotic stars.



(Photo: Dana Berry)

STORY HIGHLIGHTS
A distant "gamma ray burst" spotted in June offers clues to where gold originates in the cosmos
Such high-energy bursts are thought to result from the rare collision of two exotic neutron stars
The glow left from the burst seems to confirm the production of gold occurs in the collision's aftermath

SHARECONNECT 204TWEETCOMMENTEMAILMORE

The gold glinting on your wedding band was likely born in a cataclysmic merger of two exceedingly exotic stars, astronomers report Wednesday.

Dying stars billions of years ago cooked up most of the lighter elements in the universe, the oxygen in the air and calcium of our bones, and blasted it across the cosmos in their final explosive moments.We are stardust, as the singer Joni Mitchell put it.

But some of the heaviest atoms, including gold, defied this explanation, requiring an even more exotic origin.

A team led by Harvard astronomer Edo Berger nowreports that gold is likely created as an aftereffect of the collision of two "neutron" stars. Neutron stars are themselves the collapsed remains of imploded stars, incredibly dense stellar objects that weigh at least 1.4 times as much as the sun but which are thought to be less than 10 miles wide.

While ordinary stars explode about once every century in our galaxy, Berger says, explosive collisions of two neutron stars happen only about once every 10,000 years. And it appears they spew out gold and other heavy elements in the week after their merger.

"Call it the golden glow," Berger says. "In this case, we were able to observe it for the first time and see how the merger seems to be producing (the) heavy elements."

The team bases its finding on observations of a high-energy flash of gamma rays, a "gamma ray burst" called GRB 130603B that was detected in June by NASA's Swift X-ray telescope satellite. The burst is seen as a signature of the explosive union of two neutron stars, in this case ones some 3.9 billion light-years away (one light year is about 5.9 trillion miles) the team reports in an Astrophysical Journal Letters report.

Observation of the cloudy aftereffects of the burst suggest that each merger of two neutron stars produces several moons worth of gold by weight. "At today's prices, that amount of gold would be worth 10 octillion dollars," says Berger. (That's $10,000 trillion-trillion or $10,000,000,000,000,000,000,000,000,000, for anyone counting.)

Overall about 1% of the mass of the two neutron stars was likely converted into exotic minerals by the merger, only a small part of it gold. In the collision, sub-atomic particles blasted out of the neutron stars fuse together to form heavy elements, escaping a black hole that forms afterward from the merger. Such are the likely origins for the gold that accumulated in Earth's crust some 4.54 billion years ago, swept up from space at the birth of the solar system, and now seen in jewelry store windows.

"This means (that) the Harvard team might have discovered the 'smoking gun' for unraveling the long-standing mystery which objects in the universe are responsible for the production of gold and platinum and other heavy elements," says astrophysicist Hans-Thomas Janka of Germany's Max-Planck Institute for Astrophysics."One gets even more platinum in the same events, so even more material for mankind's jewelry!"

Janka cautioned that the gamma ray burst result represents only one observation and that astronomers will need to observe more such blasts in coming years to feel fully confident about the finding.

"It really seems that the gold in jewelry that people are wearing is the result of one of the most violent explosions in the universe: a gamma-ray burst that is produced when two neutron stars merge with each other," says astrophysicist Stephen Rosswog of Germany's Jacobs University Bremen, who first suggested the golden glow effect in 1999. "These are very difficult observations, but if this turns out to be true, this would be truly very exciting news."

The news out Wednesday says the collision of neutron stars probably generated the rare minerals such as gold that spread across the universe. An artist's depiction shows a neutron star, the crushed core of a massive star that ran out of fuel and collapsed under its own weight. NASA

From: http://www.usatoday.com/story/news/2013/07/17/gold-neutron-star/2521311/

Robots will compete against one another in disaster scenarios

A new series of robots could usher in a new era of robotics.



Photo credit:

Science Recorder | Drew Adams | Wednesday, July 17, 2013



A group of robots will be competing in a series of physical trials this December in an effort to gauge whether or not they might one day replace humans in hazardous situations.

What once was considered a favored staple of science fiction is now on the way to becoming a reality as the Defense Advanced Research Projects Agency, or DARPA, spearheads its Robotics Challenge from December 20 – 21. The competition consists of various obstacle courses that will test the limits of the robotic representatives via disaster response operations. The winning team will receive $2 million.

The Robotics Challenge website claims that “The goal of the DARPA Robotics Challenge (DRC) is to generate groundbreaking research and development so that future robotics can perform the most hazardous activities in future disaster response operations, in tandem with their human counterparts, in order to reduce casualties, avoid further destruction, and save lives.”

Six Track A customized robots will compete in the trials, including the Korea Advanced Institute of Science and Technology and Rainbow Co. developed HUBO. The current version of the humanoid machine, DRC-HUBO, will be operated by a team led by Drexel University. The other competing bots include CHIMP (Carnegie-Mellon University’s National Robotics Engineering Center), RoboSimian (NASA’s Jet Propulsion Lab), T.H.O.R. (Virginia Tech), Valkyrie (NASA’s Johnson Space Center), and a HRP-2 based robot from Japan’s SCHAFT Inc.

July 11 unveiled the Atlas robot as well, a 6-foot-2, 330 pound humanoid machine that will be used by seven Track B/C teams as they train for the December trials. Atlas was developed by Boston Dynamics and is considered one of the most advanced humanoid robots to date. It consists of a hydraulic powering system and two sets of hands that were developed by both Sandia National Labs and iRobot.

The seven Track B/C teams won the use of Atlas by progressing through DARPA’s Virtual Robotics Challenge in June. The challenge, which was the first part of DARA’s overall initiative, consisted of groups directing a virtual avatar of Atlas through computer simulated environments.

“[T]he software algorithms that were successfully employed by teams in the VRC should transfer with minor tuning to the ATLAS hardware,” stated a press release from DARPA.

Program manager for the challenge Gill Pratt elaborated further: “The Virtual Robotics Challenge was a proving ground for teams’ ability to create software to control a robot in a hypothetical scenario. The DRC Simulator tasks were fairly accurate representations of real world causes and effects, but the experience wasn’t quite the same as handling an actual, physical robot.”

A fourth track will be open to an unspecified, unfunded number of robot competitors. The event will be open to the public.

Read more: http://www.sciencerecorder.com/news/robots-will-compete-against-one-another-in-disaster-scenarios/#ixzz2ZLm4Wd6p

Nasa's Hubble telescope discovers new Neptune moon

15 July 2013 Last updated at 23:30 GMT

Voyager failed to spot the tiny moon during its 1989 fly-pass


The Hubble space telescope has discovered a new moon orbiting Neptune, Nasa has confirmed.

Designated S/2004 N 1, this is the 14th known moon to circle the giant planet.

It also appears to be the smallest moon in the Neptunian system, measuring just 20 km (12 miles) across, completing one revolution around Neptune every 23 hours.

US astronomer Mark Showalter spotted the tiny dot while studying segments of rings around Neptune.

Nasa said the moon was roughly 100 million times dimmer than the faintest star visible to the naked eye.

It is so small that the Voyager spacecraft failed to spot it in 1989 when it passed close by Neptune and surveyed the planet's system of moons and rings.

Mr Showalter's method of discovery involved tracking the movement of a white fleck appearing over and over again in more than 150 photographs taken of Neptune by Hubble between 2004 and 2009.

"The moons and arcs orbit very quickly, so we had to devise a way to follow their motion in order to bring out the details of the system," Mr Showalter explained.

"It's the same reason a sports photographer tracks a running athlete - the athlete stays in focus, but the background blurs."

From: http://www.bbc.co.uk/news/science-environment-23318301

Chemical reaction levitated by sound

16 July 2013 Last updated at 14:02 GMT

By Victoria GillScience reporter, BBC News

http://www.bbc.co.uk/news/science-environment-23332358

The water droplet and sodium particle appear to dance between the platforms



Scientists in Switzerland have designed an acoustic levitator capable of mixing substances as they hover.

The device is built of two sound-emitting platforms that trap the substances between them.

Sound waves move upward until they are reflected by the platform above. The upward- and downward-moving waves overlap, reinforcing each other in places and cancelling out in others. This traps materials in place.

The development is described in PNAS.
The researchers managed to levitate a toothpick on their acoustic squares

To demonstrate its capabilities, the researchers used it to mix a single drop of water with a single coffee grain and to bring together a minuscule grain of sodium metal with a drop of water, causing a tiny but explosive reaction. They even managed the levitate a toothpick.

Their device though needs to use very powerful sound waves to levitate even these very small droplets and particles.

Lead researcher Daniele Foresti from the Swiss Federal Institute of Technology (ETH) in Zurich, explained that to "cancel out gravity" in this way required 160 decibels of sound - higher than the 120 decibels you would hear if you stood a metre (3ft) away from a rocket launch.

"That's why we use ultrasound," Dr Foresti said.

"[Using frequencies beyond those that human ears can detect] means we won't hear it, so we can work with without any ear protection."Rocket launch

Acoustic levitators were invented in the 1980s by Nasa scientists looking for ways to simulate weightlessness. But this diminutive device is the first to be able to move and control the material it levitates.

"We have total control of the acoustic field inside," Dr Foresti said.

By making the acoustic platform of many tiny squares - each 15mm x 15mm square being its own sound-emitting device - the researchers are able to "pass" a ball of material from one of these platforms to another.

The main benefit of this remotely controlled chemical reaction is that it is contactless, meaning chemical tests could be carried out without any possibility of contamination.

"One of the tests we would like to perform is DNA transfection," said Dr Foresti.

This is the process of introducing DNA into a cell, which is a medically useful process but one that is very sensitive to contamination.

"Some of the transfection agents [chemical substances needed to carry DNA into cells] can be rendered ineffective even by plastics," said Dr Foresti,

"So this could be a way to overcome that problem."

From: http://www.bbc.co.uk/news/science-environment-23332358

NASA scientists see the heart of space weather in action

Magnetic reconnection occurs when magnetic field lines come together, break apart, and then exchange partners, snapping into place with a bolt of energy



Photo credit: NASA/SDO/RHESSI/Goddard


Science Recorder | Ellen Miller | Tuesday, July 16, 2013


Two spacecraft have captured a video of a magnificent explosion on the Sun called magnetic reconnection. Magnetic reconnection lies at the heart of explosions that occur on the surface of the Sun, a press release from NASA explains.

Magnetic reconnection occurs when magnetic field lines come together, break apart, and then exchange partners, snapping into place with a bolt of energy. Scientists at space research agencies such as NASA are seeking to better understand phenomena like magnetic reconnection because they hope that it will aide them in understanding and predicting space weather, which can affect satellites and radio communication. Because magnetic fields are invisible, it can be difficult to observe them in action.

Yang Su, a solar scientist at the University of Graz in Austria, explains that scientists are specifically seeking to understand how magnetic reconnection can cause solar flares. Scientists use computer modeling and a few observations about magnetic reconnection to try to understand this concept, but thanks to new video from two spacecraft, they will be able to take a more in-depth look at magnetic reconnection. Su discovered direct images of magnetic reconnection while looking through data from the Solar Dynamics Observatory. While a few images have been discovered before, this is the first comprehensive set that will really aide scientists in understanding what is happening when magnetic reconnection occurs and how it impacts solar and space weather.

While magnetic field lines are invisible, they force charged particles of plasma along their lengths, making them visible in images. Space telescopes pick up the lines as they arch and move along the frame of the lens. Su observed two bundles of lines move towards each other and then disconnect and reconnect.

The video offers scientists an entirely new resource since it allows them to see the phenomena in recorded time and animated, as opposed to simple photos that only offer an indication of what is happening. The team, led by Su, turned to the Reuven Ramaty High Energy Solar Spectroscopic Imager, known as RHESSI, to confirm that they were actually observing magnetic reconnection in action. RHESSI shows where hot pockets are, indicating where space weather is occurring. By combining the data, scientists were able to describe the entire process of magnetic reconnection, confirming many theories about the process as well as learning new information that they were able to observe for the first time.

Magnetic reconnection does not only occur on the surface of the sun, it also occurs near stars and within Earth’s own magnetic field, making it a key player in space weather patterns.

Read more: http://www.sciencerecorder.com/news/nasa-scientists-see-the-heart-of-space-weather-in-action/#ixzz2ZDyV86sf

Mars Rover Curiosity's Long Drive Shifts Into High Gear

By Megan Gannon, News Editor | July 15, 2013 05:24pm ET

Lower slopes of Mount Sharp appear at the top of this image taken by the right Navigation Camera (Navcam) of NASA's Mars rover Curiosity at the end of a drive of about 135 feet (41 meters) during the 329th Martian day, or sol, of the rover's work on Mars (July 9, 2013). 
Credit: NASA/JPL-Caltech


NASA's Mars rover Curiosity is pressing forward with an epic Red Planet road trip, a long-distance drive aimed at the central mountain of the robot's landing site.

Curiosity began its long Martian driveon July 4 and completed three separate trips in the days that followed. On the third leg of the 5-mile (8- kilometer) trek, the car-sized rover covered a distance of about 135 feet (41 meters), NASA officials said in a status update.

The Curiosity rover is currently driving toward Mount Sharp, a mysterious mountain that rises 3.4 miles (5.5 km) high in the middle of the rover's Gale Crater landing site. The journey will slow and long for the rover, which has a top speed across flat ground is only 0.09 mph (0.14 km/h). Since its arrival on Mars in August 2012, Curiosity has remained rather close to its landing site, traveling a total of just 0.51 miles (0.95 km), mission managers said. [See the Curiosity rover's latest photos of Mars]

WATCH THE VIDEO HERE


Curiosity is the centerpiece of NASA's $2.5 billion Mars Science Laboratory mission. It finished work at its first major science destination, an area known as Glenelg, last week. The rover is now headed southwest for the foothills of Mount Sharp. Once there, scientists hope the 1-ton robot will find clues about how Mars' ancient environment changed and evolved.

Curiosity kicked off its long drive kicked on July 4 with a 59-foot (18 m) trip, which was followed by a July 7 haul that sent the rover 131 feet (40 m) closer to Mount Sharp. The third drive, on July 9, brought Curiosity's odometer reading to about 325 feet (99 meters) since completing the Glenelg investigations, according to NASA.

Though Curiosity is not bound to a strict timeline for its trek, mission officials have estimated that it will take about a year to complete. The progress of the drive will depend on what Curiosity finds along the way, rover mission managers said.

Curiosity already has accomplished the main objective of its mission, to find out if Mars is, or once was, suitable for life. At targets in the Glenelg area, the robot drilled samples of Martian rocks that helped scientists determine thatMars could have supported microbial life in the ancient past.

NASA's Curiosity rover mission is expected to spend at least two years exploring Gale Crater, with scientists planning to eventually send the rover on a trip up Mount Sharp.

From: http://www.space.com/21966-mars-rover-curiosity-long-drive-update.html

Sun Researchers May Crack 70 Year Old Mystery

Why Is The Sun's Corona Hotter Than The Sun Itself?

Added by Georgina Pijttersen on July 13, 2013.
Saved under Georgina Pijttersen, Science



Tsunami are not limited to earth, this phenomenon has now also been sighted on the Sun, of all places. The tsunami consists of heightened magnetic field and hot, ionized gases which race across the Sun at about 400km per second. These tsunami also help cause the release matter into space, and therefore might be causing the corona surrounding the sun to be hotter than the sun surface. Therefore the researchers involved in the analysis of the data from the satellites which captured this phenomenon might have cracked a 70 year old mystery. In addition studying the effects of the sun tsunami, the matter they release into the sun’s corona and the sun orbit itself, might be an invaluable source for understanding how this all will affect Earth, and crack it’s mysterious effects on our planet.

The satellites can’t just take photographs in a regular way because this would not capture everything that is going on with the Sun. The satellites have instruments which notice, and can analyse ultraviolet light which the sun emits. Humans can’t register these colors but the satellites can. This ultraviolet light gives us information about the chemical makeup and extreme physical conditions of the Sun.

David Long of University College London and teammates spotted the waves coming from the tsunami and going into the Sun’s corona. Therefore making them the Sun’s researchers who may crack the 70 year old mystery surrounding the Sun’s corona, and why it’s hotter than the rest of the sun. The waves coming off the tsunami and going into the corona are called EIT. David said to the BBC: ”These EIT waves are quite tricky – they’re very random and they’re relatively rare,” he added, “We need to be in the right place at the right time; this has been a long time coming. This tells us a lot about the nature of the Sun and what goes on in the atmosphere,” Dr Long went on to explain. “These waves are quite important because they’re associated with CMEs that fire plasma out into the heliosphere, toward the Earth. Generally we see them when there’s a CME coming straight at us – but when it’s coming straight at us then it’s quite difficult to measure how fast it’s coming at us or how strong it is,” Long stated, ”So by looking at these waves, we should be able to infer how powerful these CMEs are going to be.”

The research hasn’t been completed yet. The researchers haven’t been able to totally crack the 70 year old mystery into why the Sun’s corona is hotter than the core temperature. It is said that the Sun’s core is some 15,000,000C, but the Sun’s surface is below 6,000C. Meanwhile the corona is known to be at a temperature in excess of 1,000,000C. Which is very odd indeed. It does seem that they are on the right track and that we will soon be able to report that indeed the Sun tsunami are responsible for changing the temperature of the Sun’s corona.

By Georgina Pijttersen

From: http://guardianlv.com/2013/07/sun-researchers-may-crack-70-year-old-mystery/

Test of new magnet is an atom-smashing success

Tia GhoseLiveScience

July 12, 2013 at 1:35 PM ET

CERN / ATLAS
This track is an example of simulated data modeled for the ATLAS detector on the Large Hadron Collider (LHC) at CERN. The Higgs boson is produced in the collision of two protons at 14 TeV and quickly decays into four muon, a type of heavy electron that is not absorbed by the detector. The tracks of the muons are shown in yellow.

A powerful new magnet to replace existing ones in the world's largest atom smasher, the Large Hadron Collider, just passed its first test with flying colors.


The magnet, which allows the massive particle collider to study two to three times more proton collisions, could help unveil the mysterious properties of the newly discovered Higgs boson, an elementary particle that is thought to explain how all other particles get their mass.

The Large Hadron Collider(LHC) between Switzerland and France sends two proton beams barreling at near light-speed around a 17-mile (27 kilometers) underground ring until they smash into each other, creating myriad subatomic particles in the process. [Beyond Higgs: 5 Elusive Particles that May Lurk in the Universe]

The new magnet produces a much larger magnetic field to focus the proton beams into an even more minuscule area, thereby ensuring that more protons crash into each other.

Focused beams
Right now, the Large Hadron Collider uses a magnet to focus the proton beams before they smash into each other. The farther the protons deviate off course, the stronger the magnet pulls them toward the center of the beam that's just a few thousandths of an inch wide. Though hundreds of billions of protons make up each beam, there are still relatively big empty spaces between them, meaning the odds of a collision are relatively small.


The current magnet is made of a superconductor called niobium titanium, which, when cooled to near absolute zero, allows large amounts of current to flow without overheating.

Niobium titanium was fine for simply discovering the Higgs boson, but revealing the properties of the Higgs boson requires more collisions than the LHC currently allows.

LBL / Fermilab
A powerful new magnet will let the Large Hadron Collider, the world's biggest atom smasher, study two to three times more proton collisions. These collisions create myriad subatomic particles such as the Higgs boson.

"The LHC is already designed at the limit of the technology," said GianLuca Sabbi, an accelerator physicist at Lawrence Berkeley Laboratory who helped design the new magnet. "So how do you make it better?"


Brittle material
The answer, it turns out, was to find a better superconductor.


One of the top candidates was niobium tin, which can produce a higher magnetic field and more current at higher temperatures.

But superconducting coils made of niobium tin are more brittle and therefore prone to moving in response to the huge forces generated as the magnet turns on. That, in turn, could release energy in the form of heat and cause the magnet to lose its superconductivity.

Higher-power magnets also cause more radiation of subatomic particles during collisions, which can damage the magnet more quickly.

To solve these problems, the team built a thick aluminum shell to support the niobium tin superconductor and prevent its displacement.

The new magnet and its housing can produce magnetic fields 50 percent stronger than the LHC's current magnet. That extra strength translates to two or three times the number of collisions, Sabbi said.

But the LHC has a bigger goal: Over 10 years, researchers plan to revamp the entire system to achieve 10 times as many collisions.

"The magnets are just one element of many changes that are going to be made in the machines," Sabbi told LiveScience.

From: http://www.nbcnews.com/science/test-new-magnet-atom-smashing-success-6C10618722

Dramatic solar tsunamis reveal magnetic secrets in sun's corona

This image from the Solar Dynamics Observatory shows the "quiet corona" and upper transition region of the sun. A study tracking solar tsunamis through the sun's plasma shows that the quiet corona may not be so quiet after all. (Solar Dynamics Observatory / NASA)


By Amina Khan
July 12, 2013, 3:50 p.m.



If tsunamis on Earth don’t seem terrifying enough, imagine the power of such a monstrous wave on the sun -- bigger, faster and made of searing plasma. Scientists have spotted two solar tsunamis that have allowed them to accurately measure the sun's magnetic field. The results, published by the journal Solar Physics, should help researchers better understand the makeup of the sun’s "quiet corona" and help predict when coronal mass ejections threaten Earth.


Solar tsunamis, spotted initially in 1997, are caused when a coronal mass ejection is hurled from the sun out into space. The eruption of charged matter pushes the surrounding plasma outward, sending out a circular wave that can travel 620 miles per second and cover half the sun’s surface in an hour, said study lead author David Long, a solar physicist at University College London.

Using NASA’s Solar Dynamics Observatory and the Japanese Hinode spacecraft, the researchers managed to capture two solar tsunamis in action, rising about 43,500 miles high and speeding along at roughly 250 miles per second. Having data from both spacecraft was key. Using NASA’s spacecraft, they tracked the tsunami by watching the ultraviolet light given off as the wave progressed. Using data from the Japanese spacecraft, they determined the density of the matter it was traveling through.

“In both of these events we were just in the right place — wasn’t too close, wasn’t too far away,” Long said.

That’s because as the tsunami spreads outward somewhat like a ripple, it gets distorted by the material it passes through. It will travel faster in denser areas and slower in less dense ones, Long said, because in dense areas the molecules are tightly packed together and can quickly relay the wave along. In sparser areas there might be a slight delay before one molecule runs into the next. The resulting raggedy circles showed that the wave was running through patchy star stuff rather than a smooth, homogeneous medium.

Together, this information allowed the scientists to determine what the density, and the magnetic field, looked like in the less active areas of the sun’s atmosphere known as the quiet corona.

"The fact that it gets deformed means that there are variations in the magnetic field of the solar atmosphere, which was very interesting," Long said. "There’s a lot more going on there than we originally thought."

Understanding a solar tsunami could also help scientists better predict the arrival of a coronal mass ejection. If such a burst of charged particles reaches Earth, it can wreak havoc on the globe’s power, electronics and navigation systems.

"If a coronal mass ejection is coming straight at you, it’s very difficult to measure its speed; it’s very difficult to measure how powerful it is," Long said. "So we are hoping that by looking at these waves, we’d be able to tell something about coronal mass ejections, which would be very useful for space weather forecasting."

From: http://www.latimes.com/news/science/sciencenow/la-sci-sn-solar-tsunami-magnetic-coronal-mass-ejection-20130712,0,280618.story

The Explosive, Beautiful Death of a Star

JUL 12, 2013 12:00 PM ET // BY JASON MAJOR



The death of a Sun-like star as seen by the Chandra and Hubble space telescopes (click to enlarge).
X-RAY: NASA/CXC/IAA-CSIC/N.RUIZ ET AL, OPTICAL: NASA/STSCI



Although they may shine for many billions of years, stars like our sun don't last forever and when it's time for them to fizzle away into the night they most certainly don't go gently -- but the result can be quite beautiful.

PHOTOS: Hubble's Latest Mind Blowing Cosmic Pictures

The image above, a composite of optical data from Hubble and x-ray observations from NASA's Chandra observatory, shows the brilliant structure of planetary nebula NGC 2392 -- a.k.a. the "Eskimo nebula."

Named for their supposed resemblance to planetary disks in early telescopes, planetary nebulae are created when stars up to about 8 times the mass of our sun run out of fuel during the final stages of their natural lives. Powerful gravitational convulsions within a failing star blast its outermost layers into space, and when the outwardly-expanding shells of material are then impacted by the star’s radiation they become ionized, causing them to glow.

PHOTOS: Ten Cosmic Stunners to Point Your New Telescope At

The comet-shaped structures surrounding NGC 2392 are created by faster wind and radiation from the central star interacting with cooler shells of dust and gas that have already been ejected.

While not achieving the dramatic level of true supernova remnants, planetary nebulae like NGC 2392 are nonetheless fascinating targets for observation, not only for their unique beauty but also for the insight they can provide as to the eventual end of our own home star, the sun.

From: http://news.discovery.com/space/astronomy/hubble-chandra-death-star-eskimo-nebula-130712.htm