Supra-arcade downflows refer to the phenomenon observed in solar physics, particularly in the study of coronal mass ejections (CMEs) and solar flares. These downflows are part of the dynamics associated with the solar corona, the outermost layer of the sun's atmosphere. In the context of solar flares, when a significant release of energy occurs, it can create shock waves and result in the ejection of plasma and magnetic field lines.
Supergranulation refers to a pattern of large-scale convective flow observed on the surface of the Sun. These are essentially massive, "super" sized cells of plasma that are significantly larger than the regular convective cells known as granules, which are typically about 1,000 kilometers in size. Supergranules can range from approximately 20,000 to 30,000 kilometers across and are thought to have lifetimes of several days.
A sun outage, also known as a solar outage, refers to a temporary disruption in satellite communication signals caused by the alignment of the sun, Earth, and the satellite. This phenomenon typically occurs during specific times of the year, usually around the equinoxes in March and September, when the sun is directly behind a satellite in geostationary orbit as viewed from Earth.
In astronomy, "Strahl" typically refers to a concept related to the study of cosmic rays, specifically the high-energy particles that travel through space. The term can also be connected to specific observational phenomena or instruments associated with astronomical studies. However, “Strahl” itself may not represent a widely recognized term or concept in astronomy, unlike terms like "radiation," "light," or "cosmic background.
Spörer's law refers to a phenomenon observed in solar physics related to solar activity and sunspot cycles. Specifically, it describes the relationship between the latitude of sunspots and their appearance over the solar cycle. According to Spörer's law, sunspots tend to form at higher latitudes during the early phases of a solar cycle and progressively appear closer to the solar equator as the cycle progresses toward its maximum phase.
A "space tornado," or more accurately termed a "space tornado," refers to a phenomenon observed in space environments, typically associated with plasma and magnetic fields rather than the atmospheric conditions we associate with tornadoes on Earth. One specific type of space tornado is found in the Earth's magnetosphere, where plasma—ionized gas made up of charged particles—can behave similarly to tornadoes in the atmosphere.
A "space hurricane" is a phenomenon that refers to a large, swirling structure of plasma and magnetic fields in the Earth's upper atmosphere, particularly in the ionosphere. This phenomenon was identified in a study published in 2021, which described a space hurricane that occurred in the Earth's atmosphere. The space hurricane is characterized by a cyclone-like structure, appearing similar to the hurricanes we see on Earth but occurring in the space environment.
The Space Weather Prediction Center (SWPC) is a part of the National Oceanic and Atmospheric Administration (NOAA) in the United States. It is responsible for monitoring and forecasting space weather, which includes phenomena such as solar flares, solar wind, geomagnetic storms, and their potential impacts on Earth and human activities. The SWPC provides critical services and information to various stakeholders, including the aviation industry, satellite operators, power grid operators, and emergency management organizations.
Solar wind is a continuous flow of charged particles, primarily electrons and protons, released from the upper atmosphere of the Sun, known as the corona. This stream of plasma travels through space at varying speeds, typically ranging from 300 to 800 kilometers per second (about 670,000 to 1.8 million miles per hour).
Solar variability refers to the fluctuations in the Sun's output of energy and radiation over various timescales, which can affect the solar system, particularly the Earth. These variations can be caused by a number of factors, primarily related to the Sun's magnetic activity, and can influence space weather, climate, and other solar system processes.
A solar storm refers to a significant disturbance in the solar wind and the Earth's magnetosphere caused by solar activity, particularly the release of energy from the sun. Key phenomena associated with solar storms include: 1. **Solar Flares**: Sudden and intense bursts of radiation emitted from the sun's surface due to the release of magnetic energy. They can produce high levels of electromagnetic radiation across the spectrum, including X-rays and ultraviolet (UV) light.
Solar spicules are dynamic structures observed in the Sun's chromosphere, which is a layer of the solar atmosphere located just above the photosphere and below the corona. Spicules are jet-like features that appear as narrow, elongated streams of plasma that erupt upward, reaching heights of several thousand kilometers. Key characteristics of solar spicules include: 1. **Formation**: Spicules are thought to be formed through the interaction of magnetic fields and the solar atmosphere.
Solar radio emission refers to the radio waves emitted by the Sun. This phenomenon occurs due to various processes and activities on the solar surface and in the solar atmosphere, particularly in relation to solar flares, sunspots, and coronal mass ejections. Solar radio emissions can provide valuable information about the physical processes occurring in the Sun, its magnetic field, and its interactions with the solar wind.
A solar prominence is a large, bright feature extending outward from the Sun's surface, often in an arch-like shape. These structures are composed of cooler, dense gas (plasma) that is suspended in the Sun's outer atmosphere, or corona, by magnetic fields. Prominences typically form in regions of strong magnetic activity, such as sunspot areas, and can extend thousands of kilometers into space.
A solar particle event (SPE) is a short-term increase in the flux of charged particles emitted by the Sun, primarily during solar flares or coronal mass ejections (CMEs). These charged particles, which mainly comprise protons, electrons, and alpha particles, are accelerated to high energies and can travel through space at significant fractions of the speed of light.
Solar minimum refers to a period of lowest solar activity in the approximately 11-year solar cycle, during which the Sun's output of solar radiation and solar phenomena, such as sunspots, solar flares, and coronal mass ejections, are at their lowest levels. During these times, the Sun exhibits fewer sunspots, which are dark regions on its surface associated with magnetic activity.
Solar maximum is a phase in the solar cycle of the Sun, characterized by an increased level of solar activity. It occurs approximately every 11 years, when the number of sunspots, solar flares, and coronal mass ejections (CMEs) reaches its peak. During this period, the Sun’s magnetic field becomes more active and complex, leading to a higher frequency of these solar phenomena.
Solar irradiance is the power per unit area received from the Sun's radiation, measured in watts per square meter (W/m²). It quantifies the intensity of sunlight hitting a surface at a specific location and time. Solar irradiance varies based on several factors, including the angle of sunlight, atmospheric conditions, and the time of year.
Solar granules are small, convective cells that form on the surface of the Sun, particularly in the photosphere, which is the visible layer of the Sun's atmosphere. Each granule typically measures about 1,000 kilometers (620 miles) across and is part of the dynamic process of convection that occurs in the Sun's outer layers. The formation of granules is driven by the rising and sinking of hot plasma.
A solar flare is a sudden, intense burst of radiation from the sun's surface, typically associated with the release of magnetic energy stored in the sun’s atmosphere. These events occur in active regions, often near sunspots, and can release a wide spectrum of electromagnetic radiation, including radio waves, visible light, ultraviolet light, and X-rays. Solar flares are caused by the complex interplay of magnetic fields in the sun.