相关实验视频
Updated: May 12, 2026

10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
在NGC 1275中,光学发射线丝的磁支是NGC 1275中的磁支
A C Fabian1, R M Johnstone, J S Sanders
1Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK. acf@ast.cam.ac.uk
Nature
|August 23, 2008
概括
磁场稳定了珀塞乌斯星团中巨大的气体丝.
科学领域:
- 天体物理学 天体物理学
- 银河系的进化 银河系的进化
- 等离子体物理学的物理学
背景情况:
- NGC 1275是一个巨大的圆星系,位于珀塞乌斯星团中,它拥有一个由古老的辐射线丝组成的星云.
- 这些细丝是由来自中央黑洞的射电发射气泡形成的,作为能量转移的标记物.
- 这些细丝在热的集群内部气体中消散的稳定机制以前是未知的.
研究的目的:
- 研究NGC 1275周围的排放线丝的结构和稳定机制.
- 为了了解这些线程如何持续存在并影响银河系的环境.
主要方法:
- 高分辨率的观测可以分辨光纤中的细结构.
- 导线尺寸的分析和与周围的集群内气体特性进行比较.
主要成果:
- 在细丝中发现了线状结构,其中一些长度超过6公分,但宽度仅为70公分.
- 有证据表明,这些线程与周围的热内部气体处于压力平衡.
结论:
- 线中磁场对于它们的稳定至关重要.
- 这种磁稳定允许冷气体积聚,可能会延迟银河系中恒星的形成.
相关概念视频
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A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
A magnetic field is defined by the force that a charged particle experiences...
A magnetic field is defined by the force that a charged particle experiences...
Magnetic 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:
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Magnetic Flux
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Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...
Magnetic Field Due to Two Straight Wires
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