During the year 2024, the sun's activity level increases as the sun continues its journey towards solar maximum; which, of course for us means a great opportunity for aurora scouting! https://t.co/3DfOQnlpVX
@ultimape yeah, Nigel did a nice tweet storm on it in december, you should follow him if you don’t
Rather, space is a hugely dynamic environment with immense scale, structure and distant impact, with intergalactic oceans of highly energetic particles and energy fields forming space conditions. This review should be kept bedside for a lifetime. https:/
We rarely have, in a single review, such a comprehensive and detailed summary of conditions in space, written in accessible language, describing a universe that is far from cold and empty. https://t.co/O218eVjrnc
“Warnings and predictions can be effectively used to schedule...maintenance operations during periods of low solar activity, while better shielding and other design improvements are key for successful operations and long lifetime of the systems.” https://t
“For prediction of the hazards...the effects are dependent both on the space environment and on the engineering and operations of the technological system, be that a telecommunication satellite or a power transmission line on ground.” https://t.co/O218eVjr
Simulation limitations “due to the limitations of the MHD approach in describing the collisionless, multicomponent plasmas in the magnetosphere.” (MHD = Magnetohydrodynamics). https://t.co/O218eVjrnc
Simulation “use still has serious limitations, both due to missing physics especially in the ionosphere and in the inner magnetosphere.” https://t.co/O218eVjrnc
“Global MHD simulations can be run in near-real time, and in many cases reproduce the observed topological changes and even in-situ measurements to quite good accuracy.” (MHD = Magnetohydrodynamics). https://t.co/O218eVjrnc
RT @TenFleming: “It is clear that such proxies include both systematic and statistical errors, which limits our capability to establish cau…
RT @TenFleming: “Large-scale or global models of the coupled solar wind-magnetosphere-ionosphere system have advanced greatly in the recent…
RT @TenFleming: “In the magnetosphere, the lack of global observations of the mass and energy circulation as well as the dynamics of the el…
RT @TenFleming: “On the ground, the largest and most harmful currents are highly localized, which makes their detection as well as predicti…
“Large-scale or global models of the coupled solar wind-magnetosphere-ionosphere system have advanced greatly in the recent past, both due to better understanding of the critical processes and due to the increased computational capabilities.” https://t.co/
RT @TenFleming: “In many instances, the magnetospheric activity can be quantitatively classified only based on a variety of magnetic indice…
“It is clear that such proxies include both systematic and statistical errors, which limits our capability to establish causal correlations.” https://t.co/O218eVjrnc
“In many instances, the magnetospheric activity can be quantitatively classified only based on a variety of magnetic indices and proxies derived using the solar wind input and the magnetic indices.” https://t.co/O218eVjrnc
“On the ground, the largest and most harmful currents are highly localized, which makes their detection as well as prediction challenging.” https://t.co/O218eVjrnc
“In the magnetosphere, the lack of global observations of the mass and energy circulation as well as the dynamics of the electromagnetic fields still limit our capabilities to evaluate the variety of physical processes.” https://t.co/O218eVjrnc
“Beginning from the solar wind observations, a single point measurement in the solar wind, sometimes far away from the Sun-Earth line, is not always sufficient to determine what impinges on the magnetopause an hour later.” https://t.co/O218eVjrnc
“Observations of the near-Earth space environment are sparse and information of the global properties are often not available, as the plasmas for the most part are too tenuous for imaging.” https://t.co/O218eVjrnc
“The SWAN instrument onboard ESA’s SOHO spacecraft is already providing first hints of activity on the far side of the Sun.” https://t.co/O218eVjrnc
“Future missions such as NASA’s STEREO will obtain a view of the far side of the Sun as well as much improved geometry for ICME detection near the Sun (viewing the propagation sideways rather than face-on).” https://t.co/O218eVjrnc
“Longer-term space weather predictions can only be given if we obtain observations from a vantage point that allows us to monitor also the face of the Sun not visible from Earth.” https://t.co/O218eVjrnc
“Solar X-ray monitors routinely monitor the Earth’s environment providing nowcasts of the space environment.” https://t.co/O218eVjrnc
“As the energetic solar particles travel to the Earth within a few tens of minutes, detection of active events in the Sun means an almost instantaneous response at Earth.” https://t.co/O218eVjrnc
“Detailed predictions of ICMEs as well as any predictions of activity driven by other solar wind and IMF structures not observable by means other than in-situ measurements are available only 30–60 minutes prior to its arrival at Earth.” https://t.co/O218eV
At the L1 distance “the solar wind monitors (presently SOHO and ACE) record the polarity and intensity of the interplanetary magnetic field and the velocity and density structure of the solar wind plasma.” https://t.co/O218eVjrnc
“Details of the storm intensity can only be predicted when the ICME has propagated to L1 distance.” https://t.co/O218eVjrnc
ICME. “The preferred leading polarity rotating from south to north is observed during the rising phase of odd-numbered solar cycles, while the opposite polarity is observed during the rising phase of even-numbered cycles.” (interplanetary magnetic cloud) h
“The polarity of the ICME structure shows a statistical dependence on the solar cycle.” (ICME = interplanetary magnetic cloud) https://t.co/O218eVjrnc
“From solar observations alone, it is impossible to detect...the structure of the magnetic field and hence the intensity and duration of the geoeffective southward field direction.” https://t.co/O218eVjrnc
“From solar observations alone, it is impossible to detect either the solar wind speed in interplanetary space (which is different from the speed near the solar surface).” https://t.co/O218eVjrnc
Fascinating exerpt from a interesting book.
“However, the effects in the near-Earth environment critically depend on the polarity of the magnetic cloud, i.e., whether the magnetic field rotates from north to south or vice versa.” https://t.co/O218eVjrnc
“Space weather warnings are given for those ICME events that propagate in a direction that probably will lead to encounter with the Earth’s space environment.” https://t.co/O218eVjrnc
“Coronal mass ejection occurrence is routinely recorded and their travel direction determined from solar coronagraph data.” https://t.co/O218eVjrnc
“When these conditions are compared against a database of earlier driver-effect events, the closest comparison event can be used as a forecast of what lies 24–48 hours ahead.” https://t.co/O218eVjrnc
“Prediction schemes have been developed based on a combination of earlier values of radiation belt fluxes, and past and present solar wind parameters.” https://t.co/O218eVjrnc
“Thus, it is possible to use the gross behavior of the outer zone electron population on day timescales using a single or a few satellites only.” https://t.co/O218eVjrnc
“Electron radiation belt climatology has shown that the entire outer radiation zone tends to vary in a relatively coherent way under the influence of major external drivers (high-speed solar wind streams, CMEs, magnetic clouds).” https://t.co/O218eVjrnc
“This means that any space weather hazard assessment must include the details of the engineering solutions in the estimates.” https://t.co/O218eVjrnc
“The current magnitudes that are a potential risk for a power transmission system are highly dependent on transformer design and on other engineering details of the network.” https://t.co/O218eVjrnc
RT @TenFleming: “The ground resistivity and the particular network configuration and its resistances have an important contribution in dete…
“This makes the observed induced current values highly variable from site to site and from system to system.” https://t.co/O218eVjrnc
“The ground resistivity and the particular network configuration and its resistances have an important contribution in determining the size of the disturbance.” https://t.co/O218eVjrnc
“The amount of induced current in a system is not directly related to the distance to the auroral currents.” https://t.co/O218eVjrnc
“In general, being related to auroral phenomena, the geomagnetically induced currents are a high-latitude problem, affecting most regions such as the Scandinavian countries, Russia, and Canada.” https://t.co/O218eVjrnc
“The first observations of space weather-associated induced currents were made already in early telegraph systems more than 150 years ago.” https://t.co/O218eVjrnc
Space weather risks on telecom. “However, metal wires are still used in parallel with optical cables for the power to repeat stations.” https://t.co/O218eVjrnc
“Telecommunication devices may experience overvoltages. As optical fibre cables do not carry induced currents, space weather risks on telecommunication equipment are probably smaller today than they were earlier.” https://t.co/O218eVjrnc
“In buried pipelines, geomagnetically induced currents and the associated pipe-to-soil voltages contribute to corrosion and disturb corrosion control surveys and protection systems.” https://t.co/O218eVjrnc
Solar geomagneticity. “The excitation current in turn induces harmonics in the electricity, unwanted relay trippings, large reactive power consumption, or voltage fluctuations, which can lead to black-outs or to permanent damage of transformers.” https://t
“In power grids, these geomagnetically induced currents cause saturation of transformers, which tends to distort and increase the excitation current.” https://t.co/O218eVjrnc
Space weather. “Affected systems include electric power transmission networks, oil and gas pipelines, telecommunication cables and railways systems.” https://t.co/O218eVjrnc
“Space weather effects are seen even on ground, as strong currents in the ionosphere can induce currents in long baseline conductor systems on ground.” https://t.co/O218eVjrnc
RT @TenFleming: Cosmic ray particles cause ionization. “These effects might be related to local decreases in the amount of cloud cover asso…
Cosmic ray particles cause ionization. “These effects might be related to local decreases in the amount of cloud cover associated with short-term changes in the cosmic rays due to increased solar activity.” https://t.co/O218eVjrnc
“At ground level, the cosmic ray particles cause ionization, and the associated vertical electric currents can influence the production of ice-forming nuclei and clouds in the upper troposphere.” https://t.co/O218eVjrnc
“The correlation of cosmic rays on only low-altitude cloud cover suggests that the cosmic rays may influence the formation of aerosols and through that the abundance of condensation nuclei in the atmosphere which can form liquid water drops.” https://t.co/
“The stronger solar wind pressure during solar maximum tends to decrease the amount of anomalous cosmic rays that can reach the inner solar system.” https://t.co/O218eVjrnc
“The global cloud coverage anomalies are correlated with the mean values of the galactic cosmic ray flux, which is modulated by the solar cycle.” https://t.co/O218eVjrnc
“The global temperature variations are correlated with a number of space physic parameters: the long term temperature anomaly follows the filtered solar cycle length, which is a measure of the intensity of the solar cycle.” https://t.co/O218eVjrnc
“The surface properties are also important for the reflected radiation, as the albedos for ice cover, vegetation, and soil are quite different.” https://t.co/O218eVjrnc
“Changes in the amount of energy radiated away from Earth can be associated with the varying amounts of greenhouse gases in the atmosphere such as carbon dioxide, methane, CFCs, or ozone.” https://t.co/O218eVjrnc
“Changes in the incoming energy may be associated with changes in cloudiness, amount of volcanic dust in the atmosphere, and amounts of either natural or anthropogenic origin aerosols.” https://t.co/O218eVjrnc
“Any change in the balance between incident and outgoing radiation can have an effect on the climate.” https://t.co/O218eVjrnc
“The ultraviolet part of the spectrum is also a strong modulator of the production of ozone, which is clearly demonstrated in the annual variation of the polar ozone holes which intensify during the local spring when the amount of UV radiation increases.”
“The total solar irradiance also varies at 27-day intervals, the variability being larger during high solar activity than during solar minimum conditions.” https://t.co/O218eVjrnc
“The “solar constant” that averages to about 1368 W/m2 has been shown to exhibit a distinct solar cycle variation.” https://t.co/O218eVjrnc
“As the amount of energy from the Sun reaching the surface of the Earth is variable, it is only natural to expect that its long-term variations would affect the large-scale climatology of the Earth.” https://t.co/O218eVjrnc
Solar nitrogen chemistry. “The effects caused by these short-lived solar proton events can last for months in the atmosphere. Similarly, relativistic electrons from the magnetosphere affect the nitrogen chemistry at somewhat higher altitudes (50–100 km).”
Solar proton products. “If sufficient downward transport is available, these nitrogen compounds can reach the stratospheric altitudes and through catalytic reaction chains to strong decrease of the stratospheric ozone.” https://t.co/O218eVjrnc
“Recent simultaneous observations of a strong increase of solar protons and the global NOx concentration in the atmosphere have clearly established the causal relationship between the solar proton events and the enhancement of odd nitrogen compounds.” http
RT @TenFleming: But outer space is a hugely dynamic place, with rivers of charged particles forming complex structures and extreme weather…
Novel cosmic chemistry. “In the middle atmosphere, precipitating energetic particles can significantly affect the chemical processes that are involved in the formation of odd nitrogen compounds.” https://t.co/O218eVjrnc
This magnificent review illustrates the dynamic nature of outer space superbly. Mandatory reading. https://t.co/O218eVjrnc
But outer space is a hugely dynamic place, with rivers of charged particles forming complex structures and extreme weather conditions, and magnetic and gravitational forces that are orders of magnitude greater than we experience. https://t.co/O218eVjrnc
Outer space is typically thought of as a cold dark empty vacuum with large planets quietly circling around, and this is how many films portray it.. https://t.co/O218eVjrnc
RT @TenFleming: Solar energetic particles. “Single event upsets can occur in electronic components when a charged particle (e.g., a heavy i…
UHF Signals. “Also this frequency range is vulnerable to the auroral currents in the ionosphere, and can be degraded or even completely lost during times of high activity.” https://t.co/O218eVjrnc
UHF Signals. “The telecommunication systems increasingly utilize ultra-high-frequency (UHF) bands to transmit signal to satellites to be relayed to other locations.” https://t.co/O218eVjrnc
HF Signals. “At times of high auroral activity, the signal can be even completely absorbed making the HF radio propagation impossible.” https://t.co/O218eVjrnc
HF Signals. “High frequency (HF) radio wave communications are most affected, as they utilize reflection from the ionosphere to carry the signal to distances beyond the local horizon.” https://t.co/O218eVjrnc
RF. “The ionosphere is heavily utilized as a transmitter of radio-frequency communication signals. As every radio amateur knows, the radio wave communication is significantly influenced by the ionospheric properties and especially the auroral currents.” ht
SATNAV Signals. “In addition, ionospheric scintillations can cause loss of signal lock and thereby lose the positioning capability.” https://t.co/O218eVjrnc
SATNAV Signals. “As the signals propagate through the ionosphere, they are refracted and slowed especially when they traverse regions of intense auroral currents.” https://t.co/O218eVjrnc
SATNAV. “Signals from several satellites are then used to calculate the observing position to high accuracy.” https://t.co/O218eVjrnc
SATNAV. “Satellite navigation systems such as the U.S. Global Positioning System (GPS) or the European Galileo operate by transmitting radio waves from the spacecraft to ground-based receivers.” https://t.co/O218eVjrnc
Solar particle radiation. “As the fluxes of energetic particles are strongly modulated by the solar activity, these problems are largest during sunspot maxima.” https://t.co/O218eVjrnc
Particle exposure. “In practice, this problem is dealt with by limiting the number of transpolar flights the crewmembers can take in a given time period.” https://t.co/O218eVjrnc
“Furthermore, as the atmospheric shielding is significantly reduced above 10 km altitude, aircraft crews and passengers on transpolar routes are subjected to increased radiation doses from the energetic particles.” https://t.co/O218eVjrnc
“The International Space Station reaches latitudes above 50°, which is sufficiently high to increase the health risks especially during extra-vehicular operations.” https://t.co/O218eVjrnc
“However, astronauts in orbit are relatively unprotected especially during the high-latitude parts of the spacecraft orbit.” https://t.co/O218eVjrnc
“The atmosphere effectively shields the Earth from high-energy particles such that only the highest-energy particles can gain access to the lower layers of the atmosphere, and only in the polar regions where the geomagnetic field is weakest.” https://t.co/
“Besides being a threat to technological systems, energetic particles pose a hazard to astronauts on space missions.” https://t.co/O218eVjrnc
“The discharge breakdown can cause physical damage which can change the satellite conductivity or thermal, chemical or optical properties.” https://t.co/O218eVjrnc
“Differential charging of spacecraft surfaces can lead to harmful discharges, which introduce noise to the system and may interrupt normal spacecraft operations and/or represent false commands for the spacecraft.” https://t.co/O218eVjrnc
Charge accumulation. “In hot, tenuous plasmas, the incident electrons and ions and the secondary photoelectrons and scattered electrons are not in current balance, which leads to potential buildup at the spacecraft.” https://t.co/O218eVjrnc
Extreme static. “Moderate-energy electrons associated with substorms cause spacecraft surface charging. During a surface charging event, insulated surfaces may charge to several kilovolts potential (typically negative relative to the ambient plasma).” http