土星中层大气中的赤道振荡
T Fouchet1, S Guerlet, D F Strobel
1LESIA, Observatoire de Paris, Université Pierre et Marie Curie, CNRS, Paris 7, Meudon F-92195, France. thierry.fouchet@obspm.fr
Nature
|May 10, 2008
概括
土星 土星 土星 土星
科学领域:
- 行星科学 行星科学
- 大气科学 大气科学
- 红外天文学 红外天文学
背景情况:
- 行星中层大气是复杂的,受到辐射,运动和波浪的影响.
- 了解这些动态对于行星科学至关重要,但建模具有挑战性.
- 在地球,木星,金星和泰坦上观察到赤道振荡和超旋转.
研究的目的:
- 用红外观测来研究土星中层大气的动态.
- 为了识别驱动土星大气现象的波形模式.
- 将土星的大气振荡与地球和木星的大气振荡进行比较.
主要方法:
- 对土星大气层的红外观测.
- 对温度概况和大气振荡的分析.
- 与地球和木星大气动态的比较研究.
主要成果:
- 土星表现出类似于地球和木星的赤道振荡.
- 观察到一个中度沉降,可能与土星的赤道运动有关.
- 土星振荡的度范围表明,土星与地球和木星有着共同的基础物理.
结论:
- 土星的大气振荡为行星中层大气中的波动动态提供了新的见解.
- 需要进一步的观测和建模来准确确定波形,波长和振幅.
- 这项研究推动了我们对中层大气动力学的比较行星学的理解.
相关概念视频
Circular Orbits and Critical Velocity for Satellites
The Moon orbits around the Earth. In turn, the Earth (and other planets) orbit the Sun. The space directly above our atmosphere is filled with artificial satellites in orbit. One can examine the circular orbit, the simplest kind of orbit, to understand the relationship between the speed and the period of planets and satellites with respect to their positions and the bodies that they orbit.
Nicolaus Copernicus (1473-1543) first suggested that the Earth and all other planets orbit the Sun in...
Nicolaus Copernicus (1473-1543) first suggested that the Earth and all other planets orbit the Sun in...
Oscillations about an Equilibrium Position
Stability is an important concept in oscillation. If an equilibrium point is stable, a slight disturbance of an object that is initially at the stable equilibrium point will cause the object to oscillate around that point. For an unstable equilibrium point, if the object is disturbed slightly, it will not return to the equilibrium point. There are three conditions for equilibrium points—stable, unstable, and half-stable. A half-stable equilibrium point is also unstable, but is named so because...
Damped Oscillations
In the real world, oscillations seldom follow true simple harmonic motion. A system that continues its motion indefinitely without losing its amplitude is termed undamped. However, friction of some sort usually dampens the motion, so it fades away or needs more force to continue. For example, a guitar string stops oscillating a few seconds after being plucked. Similarly, one must continually push a swing to keep a child swinging on a playground.
Although friction and other non-conservative...
Although friction and other non-conservative...
Forced Oscillations
When an oscillator is forced with a periodic driving force, the motion may seem chaotic. The motions of such oscillators are known as transients. After the transients die out, the oscillator reaches a steady state, where the motion is periodic, and the displacement is determined.
Oscillations In An LC Circuit
An idealized LC circuit of zero resistance can oscillate without any source of emf by shifting the energy stored in the circuit between the electric and magnetic fields. In such an LC circuit, if the capacitor contains a charge q before the switch is closed, then all the energy of the circuit is initially stored in the electric field of the capacitor. This energy is given by
Variation of Atmospheric Pressure
Change in atmospheric pressure with height is particularly interesting. The decrease in atmospheric pressure with increasing altitude is due to the decreasing gravitational force per unit area as we move away from the surface of the earth.
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...


