2020 June 17 Magnetic Streamlines of the Milky Way Image Credit: ESA, Planck; Text: Joan Schmelz (USRA) Explanation: What role do magnetic fields play in interstellar physics? Analyses of observations by ESA’s Planck satellite of emission by small magnetically-aligned dust grains reveal previo […]
2020 April 14 NGC 253: The Silver Coin Galaxy Image Credit: NOAJ: Subaru, NASA & ESA: Hubble, ESO: VLT & Danish 1.5-m; Processing & Copyright: Robert Gendler & Roberto Colombari Explanation: NGC 253 is one of the brightest spiral galaxies visible, but also one of the dustiest. Du
2020 February 21 LDN 1622: Dark Nebula in Orion Image Credit & Copyright: Min Xie Explanation: The silhouette of an intriguing dark nebula inhabits this cosmic scene. Lynds’ Dark Nebula (LDN) 1622 appears against a faint background of glowing hydrogen gas only visible in long telescopic ex
2019 October 24 Dark Seahorse in Cepheus Image Credit & Copyright: Sergio Kaminsky Explanation: Light-years across, this suggestive shape known as the Seahorse Nebula appears in silhouette against a rich, luminous background of stars. Seen toward the royal northern constellation of Cepheus, the
2019 September 27 The Annotated Galactic Center Image Credit & Copyright: Miguel Claro (TWAN, Dark Sky Alqueva) Explanation: The center of our Milky Way galaxy can be found some 26,000 light-years away toward the constellation Sagittarius. Even on a dark night, you can’t really see it thou
2019 August 27 Dark Dust and Colorful Clouds near Antares Image Credit: David McGarvey Explanation: Why is the sky near Antares and Rho Ophiuchi so dusty yet colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflectio
2019 August 26 NGC 2170: Angel Nebula Still Life Image Credit & Copyright: Juan Lozano de Haro Explanation: Is this a painting or a photograph? In this classic celestial still life composed with a cosmic brush, dusty nebula NGC 2170, also known as the Angel Nebula, shines near the image center.
就像灰尘会聚积在家里的角落和书架上，它们也会在太阳系中堆积起来，不同的是，星际尘埃聚成的是好几个环状的圈圈，围绕着我们的太阳。这些尘埃环恰好与行星的运行轨道重合，因为在行星绕太阳运行的时候，会通过万有引力的作用拖拽着这些星际尘埃，最终形成环绕太阳的尘埃圆环。 在大约46亿年前，太阳系从一片混沌中开始诞生，小行星相互冲击、彗星东碰西撞，星际尘埃就是由当时残存的碎石和碎屑组成的。这些星际尘埃散布在整个太阳系中，但又主要聚集在地球和金星的运行轨道上，形成满是颗粒的圆环，从地球上用望远镜就能看得到。通过研究这些星际尘埃的组成、由来和运动，科学家探寻着行星的诞生和太阳系中一切可见物质的组成。 最近的两项
