まとめ
シンプルなモデルは,磁気活動による太陽光照射量の変化を示しています. 太陽の最大期には太陽がより明るくなり,1980年のピークは前回の周期よりも顕著に明るくなります.
科学分野:
- 太陽物理 太陽物理学
- 恒星の放射能を照射している.
- 宇宙天気は,宇宙の天気です.
背景:
- 総太陽光照射量 (TSI) は,ゆっくりと変動する.
- これらの変動は,太陽の磁気活動,特に明るいファキュラと暗い太陽斑に関連しています.
- 以前の衛星測定 (ERBとACRIM) は,1981年から1984年のデータを提供しています.
研究 の 目的:
- 複数の太陽周期にわたる磁気活動による太陽光照射の調節をモデル化し再構築する.
- 最近の太陽周期における放射能の明るさの大きさを比較するために.
主な方法:
- 明るい磁気ファキュラからの過剰放射と暗い斑点からの減少放射に基づいた単純なモデルを開発した.
- モデルをERBとACRIMの衛星ラジオメーターデータ (1981年−1984年) と同時に検証した.
- モデルを1954年まで拡張し,3つの11年間の太陽周期を分析した.
主要な成果:
- このモデルは,観測された太陽光全照射量の緩やかな変動をうまくマッチングした.
- このモデルは,活動最大値の太陽光照射量が最小値の太陽光照射量と比較して一貫して高いことを予測しています.
- 1980年の太陽周期のピークは0.07%の明るさを示し,前2回のサイクルよりも顕著でした.
結論:
- 太陽の磁気活動は,太陽の全照射量を大幅に調節する.
- 太陽の斑点の数が少ないにもかかわらず,最も最近の太陽周期 (1980年のピーク) は,より強い放射線照射の明るさを示しました.
- 日光斑の振幅と照射量調節の関係は,すべての太陽周期で線形ではないかもしれません.
関連する概念動画
01:19Magnetic Flux
The magnetic flux measures the number of magnetic field lines passing through a given surface area. The SI unit for magnetic flux is the weber (Wb). Magnetic flux is a scalar quantity. It depends on three factors: the strength of the magnetic field B, the area through which the field lines pass, and the relative orientation of the field with the surface area.
Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...
Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...
01:28Magnetostatic Boundary Conditions
An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...
01:18Magnetic Field of a Solenoid
A solenoid is a conducting wire coated with an insulating material, wound tightly in the form of a helical coil. The magnetic field due to a solenoid is the vector sum of the magnetic fields due to its individual turns. Therefore, for an ideal solenoid, the magnetic field within the solenoid is directly proportional to the number of turns per unit length and the current. Conversely, the magnetic field outside the solenoid is zero.
Consider a solenoid with 100 turns wrapped around a cylinder of...
Consider a solenoid with 100 turns wrapped around a cylinder of...
01:19Magnetic Field Lines
The representation of magnetic fields by magnetic field lines is very useful in visualizing the strength and direction of the magnetic field. Each of the magnetic field lines forms a closed loop. The field lines emerge from the north pole (N), loop around to the south pole (S), and continue through the bar magnet back to the north pole.
Magnetic field lines follow several hard-and-fast rules:
Magnetic field lines follow several hard-and-fast rules:
01:17Magnetic Damping
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
01:23Energy In A Magnetic Field
If a magnetic field is sustained, there must be a current in a closed circuit or loop, implying some energy has been spent in creating the field. If this energy is not dissipated via the circuit's resistance, it is stored in the field.
Take an ideal inductor with zero resistance. Although it's practically impossible, assume that the coil's resistance is so small that it is practically negligible. The loss of the field's energy to dissipate thermal energy (or heat) is thus negligible.
The energy...
Take an ideal inductor with zero resistance. Although it's practically impossible, assume that the coil's resistance is so small that it is practically negligible. The loss of the field's energy to dissipate thermal energy (or heat) is thus negligible.
The energy...