# Rules of Heliogeomagnetics Diversely Coordinating Biological Rhythms and Promoting Human Health
## 1 Introduction  
The discovery of the circadian rhythm and the finding that the circadian clock coordinates half the mammalian protein-coding genome indicate the importance of time considerations for human health and life more generally [1; 2; 3; 4; 5; 6]. Studies on genetic animal models and on humans provide evidence that circadian disruption associates with metabolic and psychiatric disorders, cancer, cardiovascular diseases, and cognitive decline in the elderly [7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17].  
Our previous investigations [18; 19; 20] suggested that magnetic fluctuations in space conveyed a possible anti-aging effect: The power of the HF-component of heart rate variability (HRV) increased and the nocturnal dip in HR became more pronounced on days with higher versus lower magnetic activity. The circadian HR rhythm was also amplified by the cicrasemidian (about 12 h) component of geomagnetic fluctuations. Moreover, the circadian amplitude of the VLF-component of HRV was highly correlated with the 24 h, 12 h, and 48 h amplitudes of the geomagnetic declination index. The VLF-component is clinically important since it is an indicator of health and well-being. Reduced values are predictive of morbidity and mortality from cardiovascular disease [18; 19; 20; 21; 22; 23; 24; 25; 26]. Since physiological processes critical for life fluctuate with different frequencies, many of them shared with the near and far environment [27; 28; 29], it is no surprise that periodic components of space weather are associated with an amplified circadian HR rhythm in space. Non-photic fluctuating cosmic factors (such as magnetic disturbances and solar activity) can affect virtually every cell and electrical circuits in biological systems [30; 31; 32]. Since space weather affects humans, [PERSON] et al. [33] proposed that chromosomes (i.e., broad time structures) in biota (including humans) resonate with environmental cycles. Their study is part of chronoastrobiology. For instance, on Earth, about 7-day (ciraseptan) rhythms in human HR were more prominent during spans when they were detected in solar activity than when they were not [31].  
Possible health hazards of natural, solar-variability-driven temporal variations in the Earth's magnetic field have been controversial due to inconsistent results over the past half century. Researchers evaluated how the physical environment, including variables such as the natural variation in the geomagnetic field in and around the Earth, affect biological processes [34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 50] and human health [28; 51; 52; 53; 54; 55; 56; 57; 58; 59; 60; 61; 62; 63]. Studies were conducted in the laboratory and in the field. Environmental-organismic interactions were investigated in citizens living in magneto-biotropic regions, including subarctic and arctic areas [64].  
Herein, we illustrate the methodology used to assess effects of space weather on human physiology by analyzing data from ambulatory blood-pressure monitoring (ABPM) obtained from clinically healthy citizens in Alta, Norway. Specifically, we examine whether changes in geomagnetics affect their BP variability, focusing on circadian characteristics. Results are interpreted within the larger context of our previous studies of heart rate variability in Alta as well as on the International Space Station (ISS), leading to the proposition of rules of procedure in exploring heliogeomagnetic effects on human physiology.