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NJIT’s New Solar Telescope Unveils The Complex Dynamics Of Sunspots’ Dark Cores


NJIT’s Big Bear Solar Observatory

NJIT’s Big Bear Solar Observatory

Groundbreaking images of the Sun captured by scientists at NJIT’s Big Bear Solar Observatory (BBSO) give a first-ever detailed view of the interior structure of umbrae – the dark patches in the center of sunspots – revealing dynamic magnetic fields responsible for the plumes of plasma that emerge as bright dots interrupting their darkness. Their research is being presented this week at the first Triennial Earth-Sun Summit meeting between the American Astronomical Society’s Solar Physics Division and the American Geophysical Union’s Space Physics and Aeronomy section in Indianapolis, Ind.

The high-resolution images, taken through the observatory’s New Solar Telescope (NST), show the atmosphere above the umbrae to be finely structured, consisting of hot plasma intermixed with cool plasma jets as wide as 100 kilometers.

“We would describe these plasma flows as oscillating cool jets piercing the hot atmosphere. Until now, we didn’t know they existed. While we have known for a long time that sunspots oscillate – moderate resolution telescopes show us dark shadows, or penumbral waves, moving across the umbra toward the edge of a sunspot – we can now begin to understand the underlying dynamics,” said Vasyl Yurchyshyn, a research professor of physics at NJIT and the lead author of two recent journal articles based on the NST observations.

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The Origin Of The Magnetic Field Covering The Sun Has Been Discovered

February 20, 2015 1 comment

The magnetic field that covers the Sun and determines its behavior –the eleven year cycles no less than such conspicuous phenomena as solar spots and solar storms– also has another side to it: a magnetic web that covers the entire surface of the Sun at rest and whose net magnetic flow is greater than that of the active areas. A study led by the Institute of Astrophysics of Andalusia (IAA-CSIC) has revealed where the flow that feeds this web comes from.

The outline of the solar magnetic web coincides with the boundaries of the so-called supergranules, structures linked to the existence of hot gas rising to the surface (similar to the bubbles made by boiling water) some twenty thousand kilometers in diameter.

“We have discovered that inside these supergranules, in what is known as intranetwork, small magnetic elements appear which travel toward the outer boundaries and interact with the web”, says Milan Gosic, IAA researcher in charge of the study.

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A New View Of The Solar System: Astrophysical Jets Driven By The Sun

February 19, 2015 Leave a comment

As the sun skims through the galaxy, it flings out charged particles in a stream of plasma called the solar wind, and the solar wind creates a bubble extending far outside the solar system known as the heliosphere. For decades, scientists have visualized the heliosphere as shaped like a comet, with a very long tail extending thousands of times as far as the distance from the Earth to the sun.

New research suggests that the sun’s magnetic field controls the large-scale shape of the heliosphere “much more than had been previously thought,” says Merav Opher, associate professor of astronomy and director of the Center for Space Physics at Boston University (BU). In the new model, the magnetic field squeezes the solar wind along the sun’s North and South axes, producing two jets that are then dragged downstream by the flow of the interstellar medium through which the heliosphere moves.

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Artificial Intelligence Helps Stanford Physicists Predict Dangerous Solar Flares

January 15, 2015 Leave a comment

Credit: NASA/SDO and the AIA; EVE; and HMI science teams

Credit: NASA/SDO and the AIA; EVE; and HMI science teams

Solar flares can release the energy equivalent of many atomic bombs, enough to cut out satellite communications and damage power grids on Earth, 93 million miles away. The flares arise from twisted magnetic fields that occur all over the sun’s surface, and they increase in frequency every 11 years, a cycle that is now at its maximum.

Using artificial intelligence techniques, Stanford solar physicists Monica Bobra and Sebastien Couvidat have automated the analysis of the largest ever set of solar observations to forecast solar flares using data from the Solar Dynamics Observatory (SDO), which takes more data than any other satellite in NASA history. Their study identifies which features are most useful for predicting solar flares.

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Origin Of High-Latitude Auroras Revealed

December 18, 2014 Leave a comment

Auroras are the most visible manifestation of the Sun’s effect on Earth, but many aspects of these spectacular displays are still poorly understood. Thanks to ESA’s Cluster and NASA’s Image satellites working together, a particular type of very high-latitude aurora has now been explained.

Although separated by some 150 million kilometres, the Sun and Earth are connected by the solar wind. This stream of plasma – electrically charged atomic particles – is launched by the Sun and travels across the Solar System, carrying its own magnetic field with it.

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Huge Sunspots And Their Magnetic Structure Observed By “Hinode”

November 29, 2014 Leave a comment

Credit: Solar Flare Telescope of the Solar Observatory/NAOJ

Credit: Solar Flare Telescope of the Solar Observatory/NAOJ

In the latter half of October, huge sunspots were observed on the surface of the Sun. These sunspots appeared at the east limb of the Sun on Oct. 16, and moved to the west as the Sun rotated. They rotated out of view after Oct. 30. On Oct. 26, the total area of these sunspots became almost 66 times larger than the Earth’s cross section. This was the largest sunspot area in this solar cycle, and the largest observed in the last 24 years (since Nov. 18, 1990). In the middle of November, these sunspots appeared again at the east limb, as the Sun’s rotation brought them back into view.

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UK Leads New International Solar Storm Tracking Initiative

October 2, 2014 Leave a comment

UK scientists have unveiled a new £2.5 million (€3.2 million) project that will improve forecasts of solar storms, including their arrival time and impact on the Earth. The three year project will provide the most comprehensive set of information to date about the Sun’s influence on interplanetary space and the effects space weather can have on the Earth. The project will enable governments to improve their strategies to lessen the potential negative impacts from the Sun.

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NASA STEREO Observes One Of The Fastest CMEs On Record


Credit: NASA/STEREO

Credit: NASA/STEREO

On July 23, 2012, a massive cloud of solar material erupted off the sun’s right side, zooming out into space, passing one of NASA’s Solar TErrestrial RElations Observatory (STEREO) spacecraft along the way. Using the STEREO data, scientists at NASA’s Goddard Space Flight Center in Greenbelt, Md. clocked this giant cloud, known as a coronal mass ejection, or CME, as traveling between 1,800 and 2,200 miles per second as it left the sun.

Conversations began to buzz and the emails to fly: this was the fastest CME ever observed by STEREO, which since its launch in 2006 has helped make CME speed measurements much more precise. Such an unusually strong bout of space weather gives scientists an opportunity to observe how these events affect the space around the sun, as well as to improve their understanding of what causes them.

“Between 1,800 and 2,200 miles per second puts it without question as one of the top five CMEs ever measured by any spacecraft,” says solar scientist Alex Young at Goddard. “And if it’s at the top of that velocity range it’s probably the fastest.”

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Astronomers Find Solar Storms Behave Like Supernovae

February 24, 2014 Leave a comment

Photo credit: NASA/SDO

Photo credit: NASA/SDO

Researchers at UCL have studied the behaviour of the Sun’s coronal mass ejections, explaining for the first time the details of how these huge eruptions behave as they fall back onto the Sun’s surface. In the process, they have discovered that coronal mass ejections have a surprising twin in the depths of space: the tendrils of gas in the Crab Nebula, which lie 6500 light-years away and are millions of times larger.

On 7 June 2011, the biggest ejection of material ever observed erupted from the surface of the Sun. Over the days that followed, the plasma belched out by the Sun made its way out into space. But most of the material propelled up from the Sun’s surface quickly fell back towards our star’s surface.

For the solar physicists at UCL’s Mullard Space Science Laboratory, watching these solar fireworks was a unique opportunity to study how solar plasma behaves.

“We’ve known for a long time that the Sun has a magnetic field, like the Earth does. But in places it’s far too weak for us to measure, unless we have something falling through it. The blobs of plasma that rained down from this beautiful explosion were the gift we’d been waiting for”, says David Williams, one of the study’s authors.

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Stanford Physicists Monitoring Huge Solar Event

November 13, 2013 Leave a comment

Every 11 years, the sun undergoes a complete makeover when the polarity of its magnetic field – its magnetic north and south – flips. The effects of this large-scale event ripple throughout the solar system.

Although the exact internal mechanism that drives the shift is not entirely understood, researchers at Stanford’s Wilcox Solar Observatory have monitored the sun’s magnetic field on a daily basis since 1975 and can identify the process as it occurs on the sun’s surface. This will be the fourth shift the observatory has monitored.

New polarity builds up throughout the 11-year solar cycle as sunspots – areas of intense magnetic activity – appear as dark blotches near the equator of the sun’s surface. Over the course of a month, a sunspot spreads out, and gradually that magnetic field migrates from the equator to one of the sun’s poles.

As the polarity moves toward the pole, it erodes the existing, opposite polarity, said Todd Hoeksema, a solar physicist at Stanford since 1978 and director of the Wilcox Solar Observatory. The magnetic field gradually reduces toward zero, and then rebounds with the opposite polarity.

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