保护地球，探索宇宙，发现文明
2023年3月22日 M31: The Andromeda Galaxy Image Credit & Copyright: Abdullah Al-Harbi Explanation: How far can you see? The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy, over two million light-years away. Without a telescope, even this immense spiral galaxy appears as an unremarkable, faint, nebulous cloud in the c...
2022年7月11日 Andromeda over the Sahara Desert Credit & Copyright: Jordi Coy Explanation: What is the oldest thing you can see? At 2.5 million light years distant, the answer for the unaided eye is the Andromeda galaxy, because its photons are 2.5 million years old when they reach you. Most other apparent denizens of the night sky — stars, clusters, ...
2021年9月8日 The Deep Sky Toward Andromeda Image Credit & License: Stefan Ziegenbalg Explanation: What surrounds the Andromeda galaxy? Out in space, Andromeda (M31) is closely surrounded by several small satellite galaxies, and further out it is part of the Local Group of Galaxies — of which our Milky Way galaxy is also a member. On the sky, however,...
2020年11月25日 Andromeda over Patagonia Image Credit & Copyright: Gerardo Ferrarino Explanation: How far can you see? The Andromeda Galaxy at 2.5 million light years away is the most distant object easily seen with your unaided eye. Most other apparent denizens of the night sky — stars, clusters, and nebulae — typically range from a few hundred...