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"Prediction of solar storms and their impact on Earth is improving: a two-day warning instead of an hour, but there is still room for improvement in the models"

This is what Dr. Ofer Cohen of the Harvard-Smithsonian Observatory says, during the seminar "Solar cycle #24 and its effect on ground and space infrastructures" that took place yesterday at the Open University

A hole in the sun's corona, as photographed yesterday (27/11/2011) by the SDO spacecraft. NASA monitors space 'weather' events
A hole in the sun's corona, as photographed yesterday (27/11/2011) by the SDO spacecraft. NASA monitors space 'weather' events

"It is still difficult for us to predict the solar cycle because we do not fully understand how it works" claims Dr. Ofer Cohen from the Harvard Smithsonian Astrophysics Institute, as part of a seminar entitled "Solar Cycle No. 24 and its Impact on Ground and Space Infrastructures". The event was organized by the Department of Research and Development of the ICT Division, the Open University, Mapat, the Space Administration of Moshebat and the Fisher Institute for Strategic Air and Space Research. Prof. Yoav Yair organized the conference on behalf of the Open University.

The seminar was attended by representatives of the space industries in Israel, whose satellites and the electronic equipment inside them, manufactured in these industries, suffer from the hardships of space - large temperature differences, vacuum, and especially ionizing radiation of dimensions unknown in any other electronic application on earth. Strong radiation fluxes damage satellites when eruptions from the Sun reach the Earth's environment. The planet itself is protected by the radiation belt - the Van Allen belt, but in extreme cases, it is unable to withstand the load and the effect of the radiation also spills over to the ground, causing in some cases extreme power outages.

"I work on space weather forecasting models, in my opinion we still don't understand how the solar cycle works and we can't predict it. The models are not good enough, the computing capabilities are not fast enough and the physics is too complicated. In one of the slides, I showed the results of an appeal by NASA to all researchers involved in the field in which the agency asked them to predict the next cycle using different prediction methods. The answers were varied, some said it would be very weak and some said it was very strong and the majority were in the middle. This result shows how much we do not understand, we are not in a position to predict the next cycle and say unequivocally that it will be strong or weak."

"I suggest waiting for the models to be better, mainly it depends on the computing power that as it improves the models start to be more accurate, you have to make fewer assumptions and fewer approximations and the results are a little more understandable. Part of my work was to develop simulations based on events that had already occurred and to run the simulations from the moment of the eruption until it reaches the Earth and the comparison with the Earth measurements was with a reasonable measurement error. The input to the model was partly based on stereo and Soho satellites. This gave a prediction time of two days instead of the hour you would get from satellites orbiting the Earth."

Cohen's optimism regarding the improvement of the models is also shared by Prof. Leon Hoffman, a visiting associate professor at Tel Aviv University, who works at NASA and the Catholic University in the USA. "I presented a study on mass eruptions from the Sun's corona. These eruptions create many charged particles and magnetic fields that when they reach the Earth they cause magnetic storms and the particles can cause damage to satellites, communications and even electrical systems on Earth. The study of these phenomena is to try to predict them, to see in which active areas the eruptions can happen and to calculate their spread in space and then the effects on the Earth's magnetic fields and the magnetic storms."

"The bottom line is that we currently have a fleet of satellites that give us information that can be used to build the models and today there is a lot of progress in building models that make it possible to make predictions and currently there is already a prediction but it is not accurate enough but the research focuses on ways to improve the prediction and analyze what new data is needed in space to improve prediction. Unlike the atmosphere where we only have air and water, in space there are also magnetic fields in addition to matter, the matter is mostly neutral but there are also charged particles and it responds to the magnetic fields the models are much more computationally complex. And in addition, since we are dealing with space, the measurements are more difficult because we don't have something equivalent to the ground stations. Satellites are not as numerous as ground stations. Today the number of satellites has increased dramatically but there is still room for improvement. There is progress, but there is still room for improvement to prevent the damage of these phenomena."

Dan Willing from the Los Alamos National Laboratory presented the attempt made by a group led by him to find the connection between malfunctions in satellites and the number of solar storms occurring at the same time. "We made an attempt to quantify the effect of space weather on the operation of satellites. We do this by trying to match satellite failures with space weather events. The bottom line - this seems to be a difficult task, and many things seem consistent with the failure of the satellites, from the long-term exposure to radiation events in space, to the impact of single ion events that damaged a critical electronic component.

From examining about 5,000 faults we found such a relationship but it is difficult to quantify it because in some indices we found a relationship and in some not. There seems to be a high correlation between a large percentage of the malfunctions and space weather events, but it is difficult to detail the specific process by which the malfunction occurred.

Lt. Col. (Res.) Meir Moalem, from the company Multimodis: test cases of space system malfunctions described prominent cases of the negative effect of ionizing radiation on satellites. In 1962, the US government conducted a nuclear test at an altitude of 400 kilometers - Starfish His name. As part of the experiment, the Americans wanted to see if they could affect the Van Allen belt, and it turns out they succeeded, and for eight months after the explosion, high levels of radiation were recorded on Earth. A Telster satellite that was launched the day after the explosion passed through the radiation cloud that remained in place and its life time was significantly shortened.

Another example of non-solar radiation was a series of Soviet satellites called Rorsat, which were Soviet radar satellites launched in 1980 that were powered by a nuclear reactor. It turns out that their radiation affected other satellites that passed in orbits close to them, including NASA's Solar-Max, whose sensors were disrupted every time it passed near Rorsat satellites. The Compton satellite that explored the universe also had great difficulty working in the Rorsat environment. NASA was surprised by the levels of radiation they were not prepared for.

The radiation in the radiation belt surrounding Jupiter completely disabled the Pioneer 10 instruments and disrupted the Pioneer 11 instruments that visited there a year later.
Other cases of malfunctions in space are collisions between satellites and space junk, as in the case of the CERISE satellite or short malfunctions.

And of course many malfunctions occurred as a result of radiation events, Moalem gave several examples, first of all the case of the Galaxy 15 communication satellites.

One response

  1. "I work on space weather forecasting models, in my opinion we still don't understand how the solar cycle works and we can't predict it. The models are not good enough, the computing capabilities are not fast enough and the physics is too complicated."

    So:
    The most accurate model and the strongest computing power and the most complicated physics are not the heart of the matter.

    It is unknown and very difficult to measure the environment of the sun's surface, and there is no real idea of ​​what is happening in the core. In this case no calculation ability will help. There is simply no analytical model at all.

    And even if there is an analytical model and we know every millimeter-grid according to and inside the sun, it will not help because of the simulations in the flow laws (Naviya-Stokes equations). In the Chaos book it is best explained.

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