Giant Sunspot Keeps Firing Off Huge Solar Flares

The largest sunspot observed on the sun in more than 20 years has been firing off powerful solar flares for the past week, and it's still producing strong solar storms.

Today, the huge sunspot erupted with a large solar flare, peaking at around 10:47 a.m. EDT (1447 GMT).

The flare caused a strong radio blackout on Earth, according to the National Weather Service's Space Weather Prediction Center. This solar flare is the fourth X-flare (the most powerful kind of solar storms) in as many days.

On Sunday (Oct. 26), the giant sunspot unleashed a solar flare, which peaked at about 6:56 a.m. EDT (1056 GMT). The sunspot, called Active Region 12192 (also known as AR 2192), also shot out another powerful flare on Saturday. Today and Sunday's flares measured in at X2, while Saturday's is classified as an X1 flare.

Sunday's X2-class flare was "the third X-class flare in 48 hours, erupting from the largest active region seen on the sun in 24 years," NASA spokesperson Karen Fox wrote in an update yesterday (Oct. 26). AR 2129 also shot out an X3.1-class flare on Friday (Oct. 24).

The sun unleashed an X2-class solar flare on Oct. 26, 2014. NASA's Solar Dynamics Observatory captured this photo of the flare (lower right).

Credit: NASA/SDO

NASA Chandra observes runaway pulsar firing an extraordinary jet

Credit X-ray: NASA /CXC /ISDC /L.Pavan et al, Radio: CSIRO /ATNF /ATCA Optical: 2MASS /UMass /IPAC-Caltech /NASA /NSF

NASA's Chandra X-ray Observatory has seen a fast-moving pulsar escaping from a supernova remnant while spewing out a record-breaking jet, the longest of any object in the Milky Way galaxy, of high-energy particles.

The pulsar, a type of neutron star, is known as IGR J11014-6103.

IGR J11014-6103's peculiar behaviour can likely be traced back to its birth in the collapse and subsequent explosion of a massive star.

Originally discovered with the European Space Agency satellite INTEGRAL, the pulsar is located about 60 light-years away from the center of the supernova remnant SNR MSH 11-61A in the constellation of Carina.

Its implied speed is between 2.5 million and 5 million mph, making it one of the fastest pulsars ever observed.

Lucia Pavan

"We've never seen an object that moves this fast and also produces a jet," said Lucia Pavan of the University of Geneva in Switzerland and lead author of a paper published Tuesday in the journal Astronomy and Astrophysics.

"By comparison, this jet is almost 10 times longer than the distance between the sun and our nearest star."

The X-ray jet in IGR J11014-6103 is the longest known in the Milky Way galaxy.

In addition to its impressive span, it has a distinct corkscrew pattern that suggests the pulsar is wobbling like a spinning top.

IGR J11014-6103 also is producing a cocoon of high-energy particles that enshrouds and trails behind it in a comet-like tail.

This structure, called a pulsar wind nebula, has been observed before, but the Chandra data show that the long jet and the pulsar wind nebula are almost perpendicular to one another.

Pol Bordas

"We can see that this pulsar is moving directly away from the center of the supernova remnant based on the shape and direction of the pulsar wind nebula," said co-author Pol Bordas, from the University of Tuebingen in Germany. "The question is, why is the jet pointing off in this other direction?"

Usually, the spin axis and jets of a pulsar point in the same direction as they are moving, but IGR J11014-6103's spin axis and direction of motion are almost at right angles.

Gerd Puehlhofer

"With the pulsar moving one way and the jet going another, this gives us clues that exotic physics can occur when some stars collapse," said co-author Gerd Puehlhofer also of the University of Tuebingen.

One possibility requires an extremely fast rotation speed for the iron core of the star that exploded.

A problem with this scenario is that such fast speeds are not commonly expected to be achievable.

The supernova remnant that gave birth to IGR J11014-6013 is elongated from top-right to bottom-left in the image roughly in line with the jet's direction.

These features and the high speed of the pulsar are hints that jets could have been an important feature of the supernova explosion that formed it.

More information: arxiv.org/abs/1309.6792