Moscow is holding an international conference on space weather and its effects on the Earth and human health.
The topic is highly controversial, as up until now there are many uncertainties concerning the driving mechanisms of solar-terrestrial relations. However, when it comes to space flights and further space exploration, one cannot deny the immense influence that space radiation will have on future space travelers.
Synchronized with the Sun
Weather forecasting is not a very old phenomenon. It originated back in the years of World War II, and bloomed thanks to the help of weather satellites. Space weather observations are even younger, as solar winds, the main factor that affects the changes the Sun is undergoing at any given moment, was discovered only in the late 1950s. Even though some hints on how the Sun is linked to the Earth had existed before, experimental observations – and thus studies of solar weather – began no earlier than space exploration.
The conference titled “Space Weather Effects on Humans in Space and on Earth” is currently being held by Moscow’s Space Research Institute, with around 200 participants from 11 countries, represented by both physicists and physicians, studying the effects of solar activity upon the Earth.
Space weather is generated by the Sun, and therefore effective forecasts are tightly bound to solar research. The general idea is that solar particles constantly emitted by the Sun (solar wind) carry an interplanetary magnetic field (IMF) that interact with the Earth’s magnetic field and atmosphere in a number of ways.
Increased solar activity means a more intense particle flux that causes geomagnetic disturbances. Both the particles and geomagnetic storms can influence (mostly in a harmful manner) satellites in orbit, people in space and, possibly, on the Earth.
Luckily, mankind is more or less protected from the most energetic particles by the Earth’s atmosphere. However, geomagnetic storms are far more ubiquitous and might be a source of health problems. As Tamara Breus, the head of the Laboratory of Heliobiology mentioned at the press conference on Monday, there were a number of statistical studies that had found a strong correlation between the increased rates of heart diseases with higher solar activity. However, as she also underlined, the exact mechanism of this correlation is not known. It is supposed that the reaction to geomagnetic storms is similar to adaptation stress, which occurs with some irregularities in external factors, such as circadian cycles. Since the Sun has its own cycles, live organisms might have well adapted to them, much like we have adapted to day and night change. Thus, any disturbances cause a malfunction of the body’s internal clock, just like what happens after transcontinental flights.
Geomagnetic effects are subtle and hence almost unnoticeable for healthy people. However, they may pose a danger for those who are already ill. This is why space weather forecasting can be crucial for hospitals and similar facilities.
Climate and the Sun: a long way ahead
The solar influence upon the climate has been established, but data on solar activity is scarce as it is hard to study the long-term effects. Moreover, the Earth’s climate is too complicated to contribute any changes to only one factor. Still, there are some advances in the field.
According to Vladimir Kuznetsov – the director of the Pushkov Institute for Earth’s Magnetism, Ionosphere and Radio Wave Propagation – solar particles, which nevertheless penetrate through the Earth’s magnetic field and enter the atmosphere, can act as a center of water condensation, thus intensifying cloud formation. The cloud deck, in its turn, determines the amount of solar radiation which reaches the Earth’s surface and therefore influences the climate. However, as the studies are in the very first phase, it is hard to distinguish between space- and Earth-driven factors, especially when it comes to historical research.
More immediate effects of solar activity are easier to establish. For instance, the emerging space industry which has launched hundreds of satellites around the Earth proved to be very susceptible to energetic particles. The first victim of solar activity was the Telstar 401 telecommunication satellite, which was lost in 1997 due to a magnetic storm. Luckily, there have been no similar events in the sky, but with increasing dependence on satellites, the price of the malfunction would be much higher – especially when is comes to human flights.
The current radiation environment onboard the International Space Station is not that much worse than on the Earth’s surface, although cosmonauts have to hide in special shelters during solar bursts. But traveling further in space would mean leaving the protective geomagnetic shield and thus exposing cosmonauts to energetic particles both of solar and galactic origin. It is thus crucial to predict solar activity for any long term activity.
The problem is, Vladimir Kuznetsov noted, that no accurate model of solar dynamics exists up to date, which would allow forecasting of the Sun’s behavior, although space weather forecasts (i.e., the aftermath of solar activity) for several hours and days are possible.
Further studies might shed some light to the secret. Current solar observatories such as SOHO or STEREO have supplied the scientific community with a wealth of information on the life of our star. However, since some solar effects require significant time to reveal themselves, it would be rather hasty to expect immediate results in the next few years. Unfortunately, some space effects also take space times.