New model predicting solar flares is 56% accurate

The uncertainty of science: Using observations from the space-based Solar Dynamics Observatory (SDO), solar scientists have developed a new model for predicting the biggest solar flares, and have found it to able to predict a big flare about 56% of the time.

Kusano and his team looked at the seven active regions from the last solar cycle that produced the strongest flares on the Earth-facing side of the Sun (they also focused on flares from part of the Sun that is closest to Earth, where magnetic field observations are best). SDO’s observations of the active regions helped them locate the right magnetic boundaries, and calculate instabilities in the hot spots. In the end, their model predicted seven out of nine total flares, with three false positives. The two that the model didn’t account for, Kusano explained, were exceptions to the rest: Unlike the others, the active region they exploded from were much larger, and didn’t produce a coronal mass ejection along with the flare. [emphasis mine]

What they did was apply their model to active regions on the Sun during the last solar maximum to see if it would accurately predict the events we know did happen. The model predicted that big flares would spout from ten of twelve active regions on the Sun during the last solar cycle. In reality, only seven of those twelve active regions produced flares.

The press release minimizes the three false positives, making believe they don’t count in the total. That’s hogwash. The model got it wrong, and so these false positives must be counted just like the two false negatives.

A prediction rate of 56% is barely above random, so this model needs a lot of work. Nonetheless, it is a major step forward, because it is not based on simple statistics — counting the number of big sunspots and the number of big flares and then calculating the percentage that flare — which is how most solar science models are structured, and thus are really meaningless. Instead, this model is based an actual analysis of the behavior of the Sun’s magnetic field in big active regions when solar flares erupt. They are trying to pinpoint the precise conditions that cause the big flares, and appear to be narrowing the conditions successfully.

A minor eruption on the Sun

How about another cool image, this time a movie taken by Solar Dynamics Orbiter (SDO) back in August 13, 2018 of what they call a minor eruption on the surface of the Sun.

Because the movie is a somewhat large file, I have embedded it below the fold. Or you could go here to see a higher resolution version. This is the description by the SDO science team:

This close-up of the Sun from a two-hour period on Aug 13, 2018 shows a minor eruption of charged particles rising up and twisting about before falling back into the Sun. Imaged in extreme ultraviolet light, these kinds of events are difficult to see except when they occur along the sun’s edge, also known as the limb. At its peak the plasma rises several times the diameter of Earth. [emphasis mine]

» Read more

SDO not returning data

For reasons that remain unexplained, the Solar Dynamics Observatory (SDO) did not return to science mode after it passed through the Moon’s shadow on August 2nd.

The only information about this on the SDO webpage simply states, ” The spacecraft did not go back into Science mode at the end of the transit. SDO FOT members are looking into the issue.” notes that “Since the transit no new data have appeared on SDO public websites.”

SDO has only been in orbit for six years. It would be a shame to lose it so quickly.

UPDATE: It appears that engineers are getting SDO back into operation. Hat tip James Fincannon.

SDO celebrates its fifth year in space with a time-lapse of the Sun

Cool images! In celebration of Solar Dynamics Observatory’s fifth year in space observing the Sun, the scientists at the Goddard Space Flight Center have released a time-lapse movie showing the Sun for the past five years.

Video below the fold. It is astonishing and hypnotic. The movie images were taken one image every 8 hours beginning in 2010. If you compare the Sun at the beginning of the movie with the end, you can see the slow shifting of sunspots/flares from higher to equatorial latitudes, as is normal as the solar cycle ramps up to solar maximum and beyond.
» Read more

Using Solar Dynamics Observatory (SDO), scientists have finally identified the Sun’s predicted giant jet streams.

Using Solar Dynamics Observatory (SDO), scientists have finally identified the Sun’s predicted giant jet streams.

These large flows, bigger than any flow structures previously identified, might help explain the Sun’s rotation (which is faster at the equator than at the poles), its magnetic field, and its production of sunspots. Not surprisingly, however, the models and data do not match exactly:

Mark Miesch, a physicist at the National Center for Atmospheric Research in Boulder, Colorado, says the new study confirms modelling work he and others have done on giant convective cells4. There are, however, some differences between what the models suggest and what Hathaway’s team observed. For instance, the models indicate that giant cells should align themselves from north to south near the Sun’s equator, an arrangement that isn’t seen in the new data. In fact, points out solar physicist Junwei Zhao of Stanford University in California, most of the giant cells were seen at high latitudes, and they need to be spotted at lower latitudes as well. “Whether it will convince the community remains to be seen,” says Zhao.

Three years of Solar Dynamics Observatory images of the Sun — in three minutes.

Three years of Solar Dynamics Observatory images of the Sun — in three minutes.

I’ve posted the video below the fold. It’s quite cool.

Note that these images cover the period when the Sun was ramping up to what was hoped to be a strong solar maximum, when SDO was being designed and built. And though the Sun does appear to be active in these images, it is actually far less active than it has been for solar maximums going back at least a century.

» Read more