New Theory On Why The Sun’s Corona Is Hotter Than Its Surface

A team of researchers from the U.S., Japan and Switzerland has found possible evidence of a source of energy that could be responsible for heating the sun’s corona. In their paper published in the journal Nature Astronomy, the researchers describe studying data from the FOXSI-2 sounding rocket and what it revealed.

One of the interesting problems in space research is explaining why the sun’s atmosphere (its corona) is so much hotter than its surface. The chief problem standing in the way of an answer is the lack of suitable instruments for measuring what occurs on the sun’s surface and its atmosphere. In this new effort, the researchers used data from the FOXSI-2 sounding rocket (a rocket payload carrying seven telescopes designed to study the sun) to test a theory that suggests heat is injected into the atmosphere by multiple tiny explosions (very small solar flares) on the surface of the sun. Such flares are too small to see with most observational equipment, so the idea has remained just a theory. But now, the new data offers some evidence suggesting the theory is correct.

To test the theory, the researchers looked at X-ray emissions from the corona and found some that were very energetic. This is significant, because solar flares emit X-rays. But the team was studying a part of the sun that had no visible solar flares occurring at the time. This, of course, hinted at another source. The research team suggests the only likely source is superheated plasma that could only have occurred due to nanoflares.
The researchers acknowledge that their findings do not yet solve the coronal heating problem, but they believe they might be getting close. They note that much more research is required—next year, they point out, another sounding rocket will be launched with equipment even more sensitive than that used in the last round, offering better detection of faint X-rays. Also, plans are underway to launch a satellite capable of detecting nanoflares. If future tests can clearly identify the source of the X-rays, the coronal problem may soon be resolved.

Abstract

The processes that heat the solar and stellar coronae to several million kelvins, compared with the much cooler photosphere (5,800 K for the Sun), are still not well known1. One proposed mechanism is heating via a large number of small, unresolved, impulsive heating events called nanoflares2. Each event would heat and cool quickly, and the average effect would be a broad range of temperatures including a small amount of extremely hot plasma. However, detecting these faint, hot traces in the presence of brighter, cooler emission is observationally challenging. Here we present hard X-ray data from the second flight of the Focusing Optics X-ray Solar Imager (FOXSI-2), which detected emission above 7 keV from an active region of the Sun with no obvious individual X-ray flare emission. Through differential emission measure computations, we ascribe this emission to plasma heated above 10 MK, providing evidence for the existence of solar nanoflares. The quantitative evaluation of the hot plasma strongly constrains the coronal heating models.

New Study Proposes A Giant, Space-Based Solar Flare Shield For Earth

In today’s modern, fast-paced world, human activity is very much reliant on electrical infrastructure. If the power grids go down, our climate control systems will shut off, our computers will die, and all electronic forms of commerce and communication will cease. But in addition to that, human activity in the 21st century is also becoming increasingly dependent upon the infrastructure located in Low Earth Orbit (LEO).

Aside from the many telecommunications satellites that are currently in space, there’s also the International Space Station and a fleet of GPS satellites. It is for this reason that solar flare activity is considered a serious hazard, and mitigation of it a priority. Looking to address that, a team of scientists from Harvard University recently released a study that proposes a bold solution – placing a giant magnetic shield in orbit.

The study – which was the work of Doctor Manasavi Lingam and Professor Abraham Loeb from the Harvard Smithsonian Center for Astrophysicist (CfA) – recently appeared online under the title “Impact and Mitigation Strategy for Future Solar Flares”. As they explain, solar flares pose a particularly grave risk in today’s world, and will become an even greater threat due to humanity’s growing presence in LEO.

Solar flares have been a going concern for over 150 years, ever since the famous Carrington Event of 1859. Since that time, a great deal of effort has been dedicated to the study of solar flares from both a theoretical and observational standpoint. And thanks to the advances that have been made in the past 200 years in terms of astronomy and space exploration, much has been learned about the phenomena known as “space weather”.

At the same time, humanity’s increased reliance on electricity and space-based infrastructure have also made us more vulnerable to extreme space weather events. In fact, if the Carrington event were to take place today, it is estimated that it would cause global damage to electric power grids, satellites communications, and global supply chains.

The cumulative worldwide economic losses, according to a 2009 report by the Space Studies Board (“Severe Space Weather Events–Understanding Societal and Economic Impacts”), would be $10 trillion, and recovery would take several years. And yet, as Professor Loeb explained to Universe Today via email, this threat from space has received far less attention than other possible threats.

“In terms of risk from the sky, most of the attention in the past was dedicated to asteroids,” said Loeb. “They killed the dinosaurs and their physical impact in the past was the same as it will be in the future, unless their orbits are deflected. However, solar flares have little biological impact and their main impact is on technology. But a century ago, there was not much technological infrastructure around, and technology is growing exponentially. Therefore, the damage is highly asymmetric between the past and future.”

To address this, Lingham and Loeb developed a simple mathematical model to assess the economic losses caused by solar flare activity over time. This model considered the increasing risk of damage to technological infrastructure based on two factors. For one, they considered the fact that the energy of a solar flares increases with time, then coupled this with the exponential growth of technology and GDP.

What they determined was that on longer time scales, the rare types of solar flares that are very powerful become much more likely. Coupled with humanity’s growing presence and dependence on spacecraft and satellites in LEO, this will add up to a dangerous conjunction somewhere down the road. Or as Loeb explained:

“We predict that within ~150 years, there will be an event that causes damage comparable to the current US GDP of ~20 trillion dollars, and the damage will increase exponentially at later times until technological development will saturate. Such a forecast was never attempted before. We also suggest a novel idea for how to reduce the damage from energetic particles by a magnetic shield. This was my idea and was not proposed before.”
To address this growing risk, Lingham and Loeb also considered the possibility of placing a magnetic shield between Earth and the sun. This shield would be placed at the Earth-sun Lagrange Point 1, where it would be able to deflect charged particles and create an artificial bowshock around Earth. In this sense, this shield would protect Earth’s in a way that is similar to what its magnetic field already does, but to greater effect.

Based on their assessment, Lingham and Loeb indicate that such a shield is technically feasible in terms of its basic physical parameters. They were also able to provide a rudimentary timeline for the construction of this shield, not to mention some rough cost assessments. As Loeb indicated, such a shield could be built before this century is over, and at a fraction of the cost of what would be incurred from solar flare damage.

“The engineering project associated with the magnetic shield that we propose could take a few decades to construct in space,” he said. “The cost for lifting the needed infrastructure to space (weighting 100,000 tons) will likely be of order 100 billions of dollars, much less than the expected damage over a century.”

Interestingly enough, the idea of using a magnetic shield to protect planets has been proposed before. For example, this type of shield was also the subject of a presentation at this year’s “Planetary Science Vision 2050 Workshop”, which was hosted by NASA’s Planetary Science Division (PSD). This shield was recommended as a means of enhancing Mars’ atmosphere and facilitating crewed mission to its surface in the future.

During the course of the presentation, titled “A Future Mars Environment for Science and Exploration”, NASA Director Jim Green discussed how a magnetic shield could protect Mars’ tenuous atmosphere from solar wind. This would allow it to replenish over time, which would have the added benefit of warming Mars up and allowing liquid water to again flow on its surface. If this sounds similar to proposals for terraforming Mars, that’s because it is.

Beyond Earth and the solar system, the implications for this study are quite overwhelming. In recent years, many terrestrial planets have been found orbiting within nearby M-type (aka. red dwarf) star systems. Because of the way these planets orbit closely to their respective suns, and the variable and unstable nature of M-type stars, scientists have expressed doubts about whether or not these planets could actually be habitable.

In short, scientists have ventured that over the course of billions of years, rocky planets that orbit close to their suns, are tidally-locked with them, and are subject to regular solar flares would lose their atmospheres. In this respect, magnetic shields could be a possible solution to creating extra-solar colonies. Place a large shield in orbit at the L1 Lagrange point, and you never have to worry again about powerful magnetic storms ravaging the planet!
On top of that, this study offers a possible resolution to the Fermi Paradox. When looking for sign of Extra-Terrestrial Intelligence (ETI), it might make sense to monitor distant stars for signs of an orbiting magnetic shield. As Prof. Leob explained, such structures may have already been detected around distant stars, and could explain some of the unusual observations astronomers have made.

“The imprint of a shield built by another civilization could involve the changes it induces in the brightness of the host star due to occultation (similar behavior to Tabby’s star) if the structure is big enough. The situation could be similar to Dyson’s spheres, but instead of harvesting the energy of the star the purpose of the infrastructure is to protect a technological civilization on a planet from the flares of its host star.”

It is a foregone conclusion that as time and technology progress, humanity’s presence in (and reliance on) space will increase. As such, preparing for the most drastic space weather events the solar system can throw at us just makes sense. And when it comes to the big questions like “are we alone in the Universe?”, it also makes sense to take our boldest concepts and proposals and consider how they might point the way towards extra-terrestrial intelligence.

NEW: The Highest-Energy Cosmic Rays Originate From Unknown Galaxies

Where do cosmic rays come from? Solving a 50-year old mystery, a collaboration of researchers has discovered it is much farther than the Milky Way.

In an paper published in the scientific journal ‘Science’, the Pierre Auger Collaboration has definitively answered the question of whether cosmic particles had originated from outside the Milky Way Galaxy. Their research notes that studying the distribution of the cosmic ray arrival directions is the first step in determining where the extragalactic particles originate.

The collaborating scientists were able to make their recordings using the largest cosmic ray observatory ever built, the Pierre Auger Observatory in Argentina. Included in this collaboration are David Nitz and Brian Fick, professors of physics at Michigan Technological University.

“We are now considerably closer to solving the mystery of where and how these extraordinary particles are created, a question of great interest to astrophysicists,” says Karl-Heinz Kampert, a professor at the University of Wuppertal in Germany and spokesperson for the Auger Collaboration, which involves more than 400 scientists from 18 countries.

Cosmic rays are the nuclei of elements from hydrogen to iron. Studying them gives scientists a way to study matter from outside our solar system – and now, outside our galaxy. Cosmic rays help us understand the composition of galaxies and the processes that occur to accelerate the nuclei to nearly the speed of light. By studying cosmic rays, scientists may come to understand what mechanisms create the nuclei.

To put it simply, understanding cosmic rays and where they originate can help us answer fundamental questions about the origins of the universe, our galaxy and ourselves.

FULL ARTICLE – CLICK HERE

 

Science Of Cycles Research Support Fund

 

_________________________

Science Of Cycles Multi-Disaster Relief Initiative

Be a part of Science Of Cycles Multi-Disaster Relief Initiative. Lets come together and help those who need a helping hand. Notice I did not specify a hurricane name, why? Because there is more than Harvey and Irma heading our way. The banner is set up for you to be able to place any amount you wish.   Cheers, Mitch

 

 

 

Detecting Cosmic Rays From A Galaxy Far, Far Away

In an article published today in the journal Science, the Pierre Auger Collaboration has definitively answered the question of whether cosmic particles from outside the Milky Way Galaxy. The article notes that studying the distribution of the cosmic ray arrival directions is the first step in determining where extragalactic particles originate.

The collaborating scientists were able to make their recordings using the largest cosmic-ray observatory ever built, the Pierre Auger Observatory in Argentina. Included in this collaboration are David Nitz and Brian Fick, professors of physics at Michigan Technological University.

“We are now considerably closer to solving the mystery of where and how these extraordinary particles are created, a question of great interest to astrophysicists,” says Karl-Heinz Kampert, a professor at the University of Wuppertal in Germany and spokesperson for the Auger Collaboration, which involves more than 400 scientists from 18 countries.

Cosmic rays are the nuclei of elements from hydrogen to iron. Studying them gives scientists a way to study matter from outside our solar system — and now, outside our galaxy. Cosmic rays help us understand the composition of galaxies and the processes that occur to accelerate the nuclei to nearly the speed of light. By studying cosmic rays, scientists may come to understand what mechanisms create the nuclei.

Astronomer Carl Sagan once said, “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.”

To put it simply, understanding cosmic rays and where they originate can help us answer fundamental questions about the origins of the universe, our galaxy and ourselves.

Incredibly Energetic and Far-Traveling

It’s extremely rare for cosmic rays with energy greater than two joules to reach Earth; the rate of their arrival at the top of the atmosphere is only about one per square kilometer per year, the equivalent to one cosmic ray hitting an area the size of a soccer field about once per century.

A joule is a measurement of energy; one joule is equivalent to one 3,600th of a watt-hour. When a single cosmic ray particle hits the Earth’s atmosphere, that energy is deposited within a few millionths of a second.

Such rare particles are detectable because they create showers of electrons, photons and muons through successive interactions with the nuclei in the atmosphere. These showers spread out, sweeping through the atmosphere at the speed of light in a disc-like structure, like a giant dinner-plate, several kilometers in diameter. They contain more than 10 billion particles.

At the Pierre Auger Observatory, cosmic rays are detected by measuring the Cherenkov light — electromagnetic radiation emitted by charged particles passing through a medium, such as water, at greater than the phase velocity of light in that medium. The team measures the Cherenkov light produced in a detector, which is a large plastic structure that contains 12 tons of water. They pick up a signal in a few detectors within an array of 1,600 detectors.

The detectors are spread over 3,000 square kilometers near the town of Malargüe in western Argentina, an area comparable in size to Rhode Island. The times of arrival of the particles at the detectors, measured with GPS receivers, are used to determine the direction from which the particles came within approximately one degree.

By studying the distribution of the arrival directions of more than 30,000 cosmic particles, the Auger Collaboration has discovered an anisotropy, which is the difference in the rate of cosmic ray arrivals depending in which direction you look. This means the cosmic rays do not come uniformly from all directions; there is a direction from which the rate is higher.

The anisotropy is significant at 5.2 standard deviations (a chance of about two in ten million) in a direction where the distribution of galaxies is relatively high. Although this discovery clearly indicates an extragalactic origin for the particles, the specific sources of the cosmic rays are still unknown.

The direction points to a broad area of sky rather than to specific sources because even such energetic particles are deflected by a few tens of degrees in the magnetic field of our galaxy.

There have been cosmic rays observed with even higher energy those used in the Pierre Auger Collaboration study, some even with the kinetic energy of well-struck tennis ball. As the deflections of such particles are expected to be smaller because of their higher energy, the arrival directions should point closer to their birthplaces. Such cosmic rays are even rarer and further studies are underway to pin down which extragalactic objects are the sources.

Knowledge of the nature of the particles will aid this identification, and continuing work on this problem is targeted in the upgrade of the Auger Observatory to be completed in 2018.

ANNOUNCEMENT: Solar Eclipse ‘Live’ Streaming Sites

I have set up a ‘live stream’ site to monitor Monday’s full solar eclipse. I will list the times according to your area. I’m not sure how well the bandwidth will hold out, so I am also listing several sites which will also carry this event live.There are also links for android and iphone apps.

I am keeping a close eye on events around the world. Currently there are four areas I am watching most closely due to the current amount of registered earthquakes. These areas sit on historic faults or calderas.

Science Of Cycles ‘Live Stream’: http://www.ustream.tv/channel/W4ZGGpkUatu

Facebook Live: https://www.facebook.com/NASA/videos/10155497958441772/

Twitter/Periscope: https://www.pscp.tv/nasa

Twitch TV: https://twitch.tv/nasa

Ustream: http://www.ustream.tv/nasahdtv

YouTube: https://www.youtube.com/watch?v=wwMDvPCGeE0

TIME ZONE LINK: CLICK HERE

NASA App for iOS: http://itunes.apple.com/app/nasa-app/id334325516?mt=8

NASA App for Android: https://play.google.com/store/apps/details?id=gov.nasa

NASA App for Amazon Fire and Fire TV: http://amzn.com/B00ZVR87LQ

COMING NEXT: Current High Volume Earthquake Zones

JUST IN: New NASA Mission Explores ‘Cosmic Rain’

A new experiment set for an Aug. 14 launch to the International Space Station will provide an unprecedented look at a rain of particles from deep space, called cosmic rays, that constantly showers our planet. The Cosmic Ray Energetics And Mass mission destined for the International Space Station (ISS-CREAM) is designed to measure the highest-energy particles of any detector yet flown in space.

Cosmic Ray Energetics And Mass

The ISS-CREAM experiment will be delivered to the space station as part of the 12th SpaceX commercial resupply service mission. Once there, ISS-CREAM will be moved to the Exposed Facility platform extending from Kibo, the Japanese Experiment Module. “High-energy cosmic rays carry a great deal of information about our interstellar neighborhood and our galaxy, but we haven’t been able to read these messages very clearly,” said co-investigator John Mitchell at Goddard. “ISS-CREAM represents one significant step in this direction.”

At energies above about 1 billion electron volts, most cosmic rays come to us from beyond our solar system. Various lines of evidence, including observations from NASA’s Fermi Gamma-ray Space Telescope, support the idea that shock waves from the expanding debris of stars that exploded as supernovas accelerate cosmic rays up to energies of 1,000 trillion electron volts (PeV). That’s 10 million times the energy of medical proton beams used to treat cancer. ISS-CREAM data will allow scientists to examine how sources other than supernova remnants contribute to the population of cosmic rays.

Protons are the most common cosmic ray particles, but electrons, helium nuclei and the nuclei of heavier elements make up a small percentage. All are direct samples of matter from interstellar space. But because the particles are electrically charged, they interact with galactic magnetic fields, causing them to wander in their journey to Earth. This scrambles their paths and makes it impossible to trace cosmic ray particles back to their sources.