solar activity


Summary: Any type of variation in the appearance of energy output of the sun. (NASA Thesaurus, 1994)

Top Publications

  1. Wilson J, Cucinotta F, Shinn J, Simonsen L, Dubey R, Jordan W, et al. Shielding from solar particle event exposures in deep space. Radiat Meas. 1999;30:361-82 pubmed
    ..This safety factor is sufficient to provide adequate protection if a factor of two larger event than has ever been observed in fact occurs during the mission. ..
  2. Hu S, Kim M, McClellan G, Cucinotta F. Modeling the acute health effects of astronauts from exposure to large solar particle events. Health Phys. 2009;96:465-76 pubmed publisher
    ..Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed. ..
  3. Smart D, Shea M. The local time dependence of the anisotropic solar cosmic ray flux. Adv Space Res. 2003;32:109-14 pubmed
  4. Breus T, Pimenov K, Cornelissen G, Halberg E, Syutkina E, Baevsky R, et al. The biological effects of solar activity. Biomed Pharmacother. 2002;56 Suppl 2:273s-283s pubmed
  5. Steinhilber F, Abreu J, Beer J, Brunner I, Christl M, Fischer H, et al. 9,400 years of cosmic radiation and solar activity from ice cores and tree rings. Proc Natl Acad Sci U S A. 2012;109:5967-71 pubmed publisher
    Understanding the temporal variation of cosmic radiation and solar activity during the Holocene is essential for studies of the solar-terrestrial relationship...
  6. Ohtomo K, Kobayashi N, Sumi A, Ohtomo N. Relationship of cholera incidence to El Niño and solar activity elucidated by time-series analysis. Epidemiol Infect. 2010;138:99-107 pubmed publisher
    ..These results suggest that the cholera incidence in Bangladesh may have been influenced by the occurrence of El Niño and also by the periodic change of solar activity.
  7. Kim M, Hayat M, Feiveson A, Cucinotta F. Prediction of frequency and exposure level of solar particle events. Health Phys. 2009;97:68-81 pubmed publisher
    ..These results will be useful in implementing probabilistic risk assessment approaches at NASA and guidelines for protection systems for astronauts on future space exploration missions. ..
  8. Solanki S, Usoskin I, Kromer B, Schussler M, Beer J. Unusual activity of the Sun during recent decades compared to the previous 11,000 years. Nature. 2004;431:1084-7 pubmed
    ..According to our reconstruction, the level of solar activity during the past 70 years is exceptional, and the previous period of equally high activity occurred more than 8,..
  9. Guiot J, Corona C. Growing season temperatures in Europe and climate forcings over the past 1400 years. PLoS ONE. 2010;5:e9972 pubmed publisher
    ..Cold periods prior to the 20(th) century can be explained partly by low solar activity and/or high volcanic activity. The Medieval Warm Period (MWP) could be correlated to higher solar activity...

More Information


  1. Zhovnerchuk E. [Effect of cosmoheliophysical factors on the psychic state of patients with drug dependence]. Voen Med Zh. 2002;323:56-61 pubmed
  2. Dmitriev A, Guilfanov I, Panasyuk M. Data failures in the "Riabina-2" experiment on MIR orbital station. Radiat Meas. 2002;35:499-504 pubmed
    ..The comparison analysis of the FOP with solar activity, solar wind conditions and geomagnetic activity shows that one half of the observed data failures are owing to ..
  3. Atwell W, Saganti P, Cucinotta F, Zeitlin C. A space radiation shielding model of the Martian radiation environment experiment (MARIE). Adv Space Res. 2004;33:2219-21 pubmed
    ..The results show good agreement between the model calculations and the MARIE measurements as presented for the March 2002 dataset. ..
  4. Krause A, Speacht T, Zhang Y, Lang C, Donahue H. Simulated space radiation sensitizes bone but not muscle to the catabolic effects of mechanical unloading. PLoS ONE. 2017;12:e0182403 pubmed publisher
    ..Our results suggest that combining simulated space radiation with HLS results in additional bone loss that may not be experienced by muscle. ..
  5. Ruiz Bermejo M, Osuna Esteban S, Zorzano M. Role of ferrocyanides in the prebiotic synthesis of ?-amino acids. Orig Life Evol Biosph. 2013;43:191-206 pubmed publisher
  6. Yamaguchi Y, Yokoyama Y, Miyahara H, Sho K, Nakatsuka T. Synchronized Northern Hemisphere climate change and solar magnetic cycles during the Maunder Minimum. Proc Natl Acad Sci U S A. 2010;107:20697-702 pubmed publisher
    ..We were able to explore possible sun-climate connections through high-temporal resolution solar activity (radiocarbon contents; ?(14)C) and climate (?(18)O) isotope records derived from annual tree rings...
  7. Zeitlin C, Cleghorn T, Cucinotta F, Saganti P, Andersen V, Lee K, et al. Overview of the Martian radiation environment experiment. Adv Space Res. 2004;33:2204-10 pubmed
  8. Bartlett D, McAulay I, Schrewe U, Schnuer K, Menzel H, Bottollier Depois J, et al. Dosimetry for occupational exposure to cosmic radiation. Radiat Prot Dosimetry. 1997;70:395-404 pubmed
  9. Folberth G, Pfister G, Baumgartner D, Putz E, Weissflog L, Elansky N. The annual course of TCA formation in the lower troposphere: a modeling study. Environ Pollut. 2003;124:389-405 pubmed
  10. Doke T, Hayashi T, Kikuchi J, Sakaguchi T, Terasawa K, Yoshihira E, et al. Measurements of LET-distribution, dose equivalent and quality factor with the RRMD-III on the Space Shuttle Missions STS-84, -89 and -91. Radiat Meas. 2001;33:373-87 pubmed
    ..Then, the results of DOSTEL and TEPC are compared with those of the RRMD-III. Also, the absorbed doses obtained by TLD (Mg2SiO4) and by RRMD-III on board STS-84 and -91 are compared. ..
  11. Ambrožová I, Brabcova K, Spurny F, Shurshakov V, Kartsev I, Tolochek R. Monitoring on board spacecraft by means of passive detectors. Radiat Prot Dosimetry. 2011;144:605-10 pubmed publisher
    ..Variation of dosimetric quantities with the phase of the solar cycle and the position inside the ISS is discussed. ..
  12. Stephens D, Townsend L, Hoff J. Interplanetary crew dose estimates for worst case solar particle events based on historical data for the Carrington flare of 1859. Acta Astronaut. 2005;56:969-74 pubmed
    ..These estimated doses are life threatening unless substantial shielding is provided...
  13. Cleghorn T, Saganti P, Zeitlin C, Cucinotta F. Solar particle events observed at Mars: dosimetry measurements and model calculations. Adv Space Res. 2004;33:2215-8 pubmed
    ..The dose rates at Martian orbit are calculated, both for the galactic and solar components of the ionizing particle radiation environment. The dose rates due to galactic cosmic rays (GCR) agree well with the HZETRN model calculations. ..
  14. Badhwar G. Shuttle radiation dose measurements in the International Space Station orbits. Radiat Res. 2002;157:69-75 pubmed
    ..have provided data that cover the expected changes in the dose rates due to changes in altitude and changes in solar activity from the solar minimum to the solar maximum of the current 23rd solar cycle...
  15. Romero Weaver A, Wan X, Diffenderfer E, Lin L, Kennedy A. Kinetics of neutrophils in mice exposed to radiation and/or granulocyte colony-stimulating factor treatment. Radiat Res. 2013;180:177-88 pubmed publisher
    ..Thus, these results suggest that pegfilgrastim could be a potential countermeasure for the reduced number of circulating neutrophils in irradiated animals. ..
  16. O brien K, Sauer H. The atmospheric radiation response to solar-particle-events. Adv Space Res. 2003;32:73-80 pubmed
  17. . Radiation on the Mir Orbital Station. Special issue. Radiat Meas. 2002;35:375-543 pubmed
  18. Kaul R, Barghouty A, Dahche H. Space radiation transport properties of polyethylene-based composites. Ann N Y Acad Sci. 2004;1027:138-49 pubmed
    ..This paper presents measured and calculated results for the radiation transport properties of these samples. ..
  19. Obana A, Takahashi J, Ohnishi K, Shinohara H, Matsuo A, Saito I, et al. [Survey of ocular injury by solar eclipse 2009]. Nippon Ganka Gakkai Zasshi. 2011;115:589-94 pubmed
    ..Those who reported adverse symptoms did not comply with the instructions for safe watching of the eclipse and the duration of the symptoms depended on the weather and the type of device used. ..
  20. Smart D, Shea M. Comment on estimating the solar proton environment that may affect Mars missions. Adv Space Res. 2003;31:45-50 pubmed
    ..leading to the spacecraft position represent the "classical" solar particle event associated with solar activity. This class of event will scale in radial distance by the classical power law extrapolation...
  21. Kovac M, Mikulecky M. Secular rhythms and Halberg's paraseasonality in the time occurrence of cerebral stroke. Bratisl Lek Listy. 2005;106:423-7 pubmed
    ..To honour the nestor of the world chronobiology, who highly acknowledged the work of Ladislav Dérer, the designation "Halberg's paraseasonality" is proposed (Tab. 2, Fig. 3, Ref. 17). ..
  22. Hu W, Connell D, Mengersen K, Tong S. Weather variability, sunspots, and the blooms of cyanobacteria. Ecohealth. 2009;6:71-8 pubmed publisher
    ..When minimum temperature exceeded 18 degrees C and relative humidity was under 66%, the number of cyanobacterial cells rose by 2.15-fold. We conclude that weather variability and sunspot activity may affect cyanobacteria blooms in dams. ..
  23. Shay J, Cucinotta F, Sulzman F, Coleman C, Minna J. From mice and men to earth and space: joint NASA-NCI workshop on lung cancer risk resulting from space and terrestrial radiation. Cancer Res. 2011;71:6926-9 pubmed publisher
    ..The workshop examined preclinical models, epidemiology, molecular markers, "omics" technology, radiobiology issues, and lung stem cells that relate to the development of lung cancer. ..
  24. Benton E, Benton E. Space radiation dosimetry in low-Earth orbit and beyond. Nucl Instrum Methods Phys Res B. 2001;184:255-94 pubmed
    ..While space crews in LEO are unlikely to exceed the exposure limits recommended by such groups as the NCRP, dose equivalents of the same order as the recommended limits are likely over the course of a human mission to Mars. ..
  25. Ferrari A, Pelliccioni M, Villari R. Evaluation of the influence of aircraft shielding on the aircrew exposure through an aircraft mathematical model. Radiat Prot Dosimetry. 2004;108:91-105 pubmed
    ..Likewise due consideration must be taken when positioning detectors which are used to measure H*(10). Care would be needed to avoid ambiguity when comparing the results of calculation with the experimental data. ..
  26. Segura A, Walkowicz L, Meadows V, Kasting J, Hawley S. The effect of a strong stellar flare on the atmospheric chemistry of an earth-like planet orbiting an M dwarf. Astrobiology. 2010;10:751-71 pubmed publisher
    ..Given that AD Leo is one of the most magnetically active M dwarfs known, this conclusion should apply to planets around other M dwarfs with lower levels of chromospheric activity. ..
  27. Rizvi A, Pecaut M, Slater J, Subramaniam S, Gridley D. Low-dose ?-rays modify CD4(+) T cell signalling response to simulated solar particle event protons in a mouse model. Int J Radiat Biol. 2011;87:24-35 pubmed publisher
    ..The data demonstrate, for the first time, that protracted exposure to LDR ?-rays can significantly modify the effects of sSPE protons on critical survival/signalling proteins and immunomodulatory cytokines produced by CD4(+) T cells. ..
  28. Lewis B, Bennett L, Green A, McCall M, Ellaschuk B, Butler A, et al. Galactic and solar radiation exposure to aircrew during a solar cycle. Radiat Prot Dosimetry. 2002;102:207-27 pubmed
    ..This model has been compared to results obtained during recent solar flare events. ..
  29. Kushin V. Measurement of LET distribution and absorbed dose from secondary particles on board the spacecraft. Radiat Prot Dosimetry. 2010;141:199-204 pubmed publisher
    ..The contribution of secondaries of different origin to the total LET spectrum is estimated. ..
  30. Colgan P, Synnott H, Fenton D. Individual and collective doses from cosmic radiation in Ireland. Radiat Prot Dosimetry. 2007;123:426-34 pubmed
    ..While this is low compared with the per caput doses from other sources of cosmic radiation, aircrew exposure represents a higher collective dose than any other identified group of exposed workers in Ireland. ..
  31. Cornelissen G, Halberg F, Pöllmann L, Pöllmann B, Katinas G, Minne H, et al. Circasemiannual chronomics: half-yearly biospheric changes in their own right and as a circannual waveform. Biomed Pharmacother. 2003;57 Suppl 1:45s-54s pubmed
    ..suprachiasmatic nuclei (SCN), in circulating melatonin at middle latitudes at night during years of minimal solar activity or around noon at high latitudes, and in an unusual circasemiannual aspect of a birth-month-dependence of ..
  32. Hodell D, Brenner M, Curtis J, Guilderson T. Solar forcing of drought frequency in the Maya lowlands. Science. 2001;292:1367-70 pubmed
    ..records of cosmogenic nuclide production (carbon-14 and beryllium-10) that is thought to reflect variations in solar activity. We conclude that a significant component of century-scale variability in Yucatan droughts is explained by ..
  33. Fedoseev G. [Anthropogenic sources of radiation hazard in the near-Earth space]. Aviakosm Ekolog Med. 2004;38:3-14 pubmed
    ..Specifically, consideration is given to the facts of negative effects of space power reactor facilities on results of orbital astrophysical investigations. ..
  34. Varakin I, Ionova V, Sazanova E, Sergeenko N. [The wavelet analysis at heliobiological connections]. Biofizika. 2004;49:742-6 pubmed
    ..During heliogeophysipal disturbances, the energy contribution to the processes increases more than threefold compared with the mean value on scales from three to five days. ..
  35. Badhwar G, Patel J, Cucinotta F, Wilson J. Measurements of the secondary particle energy spectra in the Space Shuttle. Radiat Meas. 1995;24:129-38 pubmed
    ..This revised code leads to about 10% higher dose equivalent than the original code under moderate shielding, if we assume that higher charge ion fluxes are correctly predicted by the model. ..
  36. Sanzari J, Wan X, Wroe A, Rightnar S, Cengel K, Diffenderfer E, et al. Acute hematological effects of solar particle event proton radiation in the porcine model. Radiat Res. 2013;180:7-16 pubmed publisher
  37. Badhwar G, Atwell W, Reitz G, Beaujean R, Heinrich W. Radiation measurements on the Mir Orbital Station. Radiat Meas. 2002;35:393-422 pubmed
    ..6 +/- 0.5 degrees N. These measurements are of direct applicability to the International Space Station. This paper represents a comprehensive review of Mir Space Station radiation data available from a variety of sources. ..
  38. Thomson M. Neutrino oscillations. Philos Trans A Math Phys Eng Sci. 2002;360:921-38 pubmed
    ..This article describes the main features and the most significant experimental observations of this unusual application of the principle of interference. ..
  39. Deeley K, Duldig M, Humble J. Re-analysis of the cosmic ray ground level enhancement of 4 May 1960. Adv Space Res. 2002;30:1049-52 pubmed
    ..The standard method involves comparison of data from two relatively close stations at significantly different altitude. We have shown that this method may be unreliable in cases, such as this, of quite sharp anisotropy. ..
  40. Karnaukhova N, Sergievich L, Karnaukhov V, Karnaukhov A, Rodionov A, Karnaukhov V. [Changes in fluorescence spectral characteristics of blood nuclear cells by the action of physical factors associated with 11- and 22-year cyclic variations in solar activity]. Biofizika. 2004;49:539-44 pubmed
    ..A change in the sign of the correlation coefficients at the maximum of the 23rd solar cycle was shown. Possible mechanisms of the phenomena are discussed. ..
  41. Townsend L, Cucinotta F, Heilbronn L. Nuclear model calculations and their role in space radiation research. Adv Space Res. 2002;30:907-16 pubmed
    ..Model shortcomings are discussed and future needs presented. ..
  42. Gulkilik G, Taskapili M, Kocabora S, Demirci G, Muftuoglu G. Association between visual acuity loss and optical coherence tomography findings in patients with late solar retinopathy. Retina. 2009;29:257-61 pubmed publisher
    ..Decreased central foveal thickness and full-thickness empty spaces beneath the fovea in optical coherence tomography analysis can be associated with permanent visual acuity loss in patients with a history of watching a solar eclipse. ..
  43. Mitsutake G, Otsuka K, Hayakawa M, Sekiguchi M, Cornelissen G, Halberg F. Does Schumann resonance affect our blood pressure?. Biomed Pharmacother. 2005;59 Suppl 1:S10-4 pubmed
    ..004-0.016). Neither subjective health nor depression was significantly associated with BPR-SR. Future studies based on larger sample sizes are planned to see whether possible health effects can be generalized. ..
  44. De Angelis G, Clowdsley M, Nealy J, Tripathi R, Wilson J. Radiation analysis for manned missions to the Jupiter system. Adv Space Res. 2004;34:1395-403 pubmed
    ..Particle transport has been performed with the HZETRN heavy ion code for hadrons and with an in-house developed transport code for electrons and bremsstrahlung photons. The obtained doses have been compared to dose exposure limits. ..
  45. Spillantini P, Taccetti F, Papini P, Rossi L, Casolino M. Radiation shielding of astronauts in interplanetary flights: the CREAM surveyor to Mars and the magnetic lens system for a spaceship. Phys Med. 2001;17 Suppl 1:249-54 pubmed
    ..A parallel technical study is also in progress to define the workable techniques and the possible configurations of a system of magnetic lenses for protecting the crew of a spaceship. ..
  46. Xu Y, Wong K, Leung C. Generalized RLS approach to the training of neural networks. IEEE Trans Neural Netw. 2006;17:19-34 pubmed
    ..Simulation results show that our approach is able to meet the design goals: improving the generalization ability of the trained network while getting a compact network. ..
  47. Zhou Y, Ni H, Li M, Sanzari J, Diffenderfer E, Lin L, et al. Effect of solar particle event radiation and hindlimb suspension on gastrointestinal tract bacterial translocation and immune activation. PLoS ONE. 2012;7:e44329 pubmed publisher
    ..The identification of mechanisms responsible for immune dysfunction during extended space missions will allow the development of specific countermeasures. ..
  48. Krigsfeld G, Savage A, Sanzari J, Wroe A, Gridley D, Kennedy A. Mechanism of hypocoagulability in proton-irradiated ferrets. Int J Radiat Biol. 2013;89:823-31 pubmed publisher
    ..SPE-like proton radiation results in significant decreases in all WBC counts as well as activates secondary hemostasis; together, these data suggest severe risks to astronaut health from exposure to SPE radiation. ..
  49. Vaquero J, Gallego M. Sunspot numbers can detect pandemic influenza A: the use of different sunspot numbers. Med Hypotheses. 2007;68:1189-90 pubmed
  50. Baek B, Aneja V, Tong Q. Chemical coupling between ammonia, acid gases, and fine particles. Environ Pollut. 2004;129:89-98 pubmed
    ..The observed [NH(3)][HNO(3)] products exceeded values predicted by theoretical equilibrium constants, due to a local excess of ammonia concentration. ..
  51. Stoupel E, Babayev E, Babyev E, Mustafa F, Abramson E, Israelevich P, et al. Acute myocardial infarction occurrence: environmental links - Baku 2003-2005 data. Med Sci Monit. 2007;13:BR175-9 pubmed
    ..activity (GMA) levels (I(0)-IV(0)) and cosmic ray activity (CRA), described by neutron (imp/min) and solar activity. The same comparison was made for pre-admission fatal AMIs (n=440)...
  52. Krigsfeld G, Savage A, Billings P, Lin L, Kennedy A. Evidence for radiation-induced disseminated intravascular coagulation as a major cause of radiation-induced death in ferrets. Int J Radiat Oncol Biol Phys. 2014;88:940-6 pubmed publisher
    ..The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals. ..
  53. Stoupel E, Sirota L, Osovsky M, Klinger G, Abramson E, Israelevich P, et al. Monthly number of preterm births and environmental physical activity. J Basic Clin Physiol Pharmacol. 2007;18:149-57 pubmed
    ..02). The monthly number of preterm births showed a significant and direct correlation with solar activity indices (r = .32, p = ...