Tuesday, November 19, 2013

The Sun Will "Flip Upside Down" In Few Weeks

The Sun is set to "flip upside down" within weeks as its magnetic field reverses polarity in an event that will send ripple effects throughout the solar system.

Although it may sound like a catastrophic occurrence, there's no need to run for cover. The sun switches its polarity, flipping its magnetic north and south, once every eleven years through an internal mechanism about which little is understood.

The swap could however cause intergalactic weather fronts such as geomagnetic storms, which can interfere with satellites and cause radio blackouts.

Nasa said in August that the change would happen in three to four months time, but it is impossible to give a more specific date. Scientist won't know for around another three weeks whether the flip is complete.

The impact of the transfer will be widespread as the sun's magnetic field exerts influence well beyond Pluto, past Nasa's Voyager probes positioned near the edge of interstellar space.

The event will be watched closely by researchers at Stanford University's Wilcox Solar Observatory, which monitors the sun's magnetic field on a daily basis.

Todd Hoeksema, director of the Wilcox Solar Observatory, said the polarity change is built up throughout the eleven year cycle through areas of intense magnetic activity known as sunspots which gradually move towards the poles, eroding the existing opposite polarity.

Eventually, the magnetic field reduces to zero, before rebounding with the opposite polarity. "It's kind of like a tide coming in or going out," Hoeksema said. "Each little wave brings a little more water in, and eventually you get to the full reversal."

One of the most noticeable effect on Earth will be a boost in the occurrence, range and visibility of auroras - the Northern Lights. "It's not a catastrophic event, it's a large scale event that has some real implications, but its not something we need to worry about," added Hoeksema.

Source: Times Of India
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- Unknown Updated at: Tuesday, November 19, 2013

Wednesday, August 7, 2013

Science : Sun's Magnetic Field To Change In Few Months

Measurements from NASA-supported observatories suggest that the sun’s vast magnetic field is about to flip.

“It looks like we’re no more than three to four months away from a complete field reversal,” solar physicist Todd Hoeksema of Stanford University, said.

“This change will have ripple effects throughout the solar system,” he said.

The sun’s magnetic field changes polarity approximately every 11 years.

It happens at the peak of each solar cycle as the sun’s inner magnetic dynamo re-organizes itself.

The coming reversal will mark the midpoint of Solar Cycle 24. Half of “solar max” will be behind us, with half yet to come.

Hoeksema is the director of Stanford’s Wilcox Solar Observatory, one of the few observatories in the world that monitors the sun’s polar magnetic fields.

The poles are a herald of change. Just as Earth scientists watch our planet’s polar regions for signs of climate change, solar physicists do the same thing for the sun.

Magnetograms at Wilcox have been tracking the sun’s polar magnetism since 1976, and they have recorded three grand reversals—with a fourth in the offing.

Solar physicist Phil Scherrer, also at Stanford, describes what happens: “The sun’s polar magnetic fields weaken, go to zero and then emerge again with the opposite polarity. This is a regular part of the solar cycle.