Galactic Astronomy Astronomy

3 个科学问题 · 天文 Astronomy

本页目录

类星体和活动星系核的能量来源是什么?

What powers quasars and active galactic nuclei?

类星体是活动星系核的一种极端形式,其能量来自中央超大质量黑洞吸积周围气体时释放的引力能。物质在吸积盘中螺旋下落,摩擦升温到极高温度并发出从射电到X射线的宽谱辐射,部分以相对论性喷流形式喷出。施密特1963年测定3C 273的红移,确认它们是极遥远、极明亮的天体。
A quasar is an extreme form of active galactic nucleus powered by a central supermassive black hole releasing gravitational energy as it accretes surrounding gas. Material spirals inward through a disk, heated by friction to extreme temperatures and emitting broadband radiation from radio to X-rays, sometimes in relativistic jets. Schmidt's 1963 redshift of 3C 273 established them as extraordinarily distant, luminous objects.
难度 专业 · 适合 高中(15-18) CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source

Schmidt《3C 273 redshift》(1963,Nature);Rees《Astrophysical jets》(1984,Annual Review of Astronomy & Astrophysics);NASA 钱德拉X射线天文台

Schmidt, 3C 273 redshift (1963, Nature); Rees, Astrophysical jets (1984, ARA&A); NASA Chandra X-ray Observatory

#类星体 #活动星系核 #超大质量黑洞

银河系中心的棒旋结构是如何被证实的?

How was the barred structure at the center of the Milky Way confirmed?

长期的天体测量显示银河系中心方向存在非轴对称的质量分布,恒星的运动模式偏离纯旋臂盘。通过近红外测光穿透尘埃,以及盖亚卫星对恒星自行的精确测量,天文学家确认了贯穿银心的长棒结构。这一棒结构引导气体向内流动,促进了中央核球的形成。
Decades of astrometry revealed a non-axisymmetric mass distribution toward the Galactic center, with stellar motions deviating from a pure disk. Near-infrared photometry piercing the dust, together with Gaia's precise stellar proper motions, confirmed a long bar across the central region. This bar funnels gas inward and helps build up the central bulge.
难度 专业 · 适合 高中(15-18) CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source

Weinberg《The bar in the Milky Way》(1992,ApJ);ESA 盖亚(Gaia)任务

Weinberg, The bar in the Milky Way (1992, ApJ); ESA Gaia mission

#银河系 #棒旋结构 #盖亚卫星

人马座A*是什么,事件视界望远镜如何拍到它的影像?

What is Sagittarius A*, and how did the Event Horizon Telescope image it?

人马座A*是银河系中心质量约400万倍太阳的超大质量黑洞,长期通过周围恒星的轨道被精确认证。事件视界望远镜把全球射电望远镜组成相当于地球大小的干涉阵列,在1.3毫米波长捕捉到环绕黑洞阴影的发光环。2022年公布的影像直接验证了广义相对论在强引力区的预言。
Sagittarius A* is the Milky Way's central supermassive black hole, about 4 million solar masses, confirmed for decades through the orbits of nearby stars. The Event Horizon Telescope linked radio dishes worldwide into an Earth-sized interferometer and captured the glowing ring around the black hole's shadow at 1.3 mm wavelength. The 2022 image directly tested general relativity in the strong-gravity regime.
难度 进阶 · 适合 高中(15-18) CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source

出处备注:著录含书名,但缺版次 / 出版社 / 年份中的一部分,需编辑补全后才能做独立比对。

事件视界望远镜合作组《First Sagittarius A* image》(2022,ApJL);Genzel 与 Ghez(2020年诺贝尔物理学奖)

Event Horizon Telescope Collaboration, First Sagittarius A* image (2022, ApJL); Genzel & Ghez (Nobel Prize in Physics 2020)

#人马座A* #超大质量黑洞 #事件视界望远镜