言行自由
发表于 2025-3-23 12:55:32
http://reply.papertrans.cn/39/3878/387724/387724_11.png
某人
发表于 2025-3-23 15:00:05
https://doi.org/10.1007/978-3-658-44604-8re accessible, the nights can be dreadfully short. In the UK, for example, if you happen to live north of the Midlands, high summer is invariably attended by perpetual twilight, until darker skies return at the end of July and early August. Even so, there are still many objects that can be favorably
tattle
发表于 2025-3-23 20:28:58
http://reply.papertrans.cn/39/3878/387724/387724_13.png
北极熊
发表于 2025-3-24 00:34:18
http://reply.papertrans.cn/39/3878/387724/387724_14.png
EPT
发表于 2025-3-24 03:38:25
Grab ‘n’ Go CATshe market to make that a rewarding reality for newcomers eager to cut their teeth in the hobby. And that’s not only true of the more traditional designs, such as refractors and Newtonian reflectors, but it is now equally valid when one considers the rich assortment of economical catadioptric telesco
OASIS
发表于 2025-3-24 09:14:36
Choosing a Mount for Your Telescoperlier chapters come with their own dedicated mounts, small refractors—which have proven to be enormously popular as grab ‘n’ go telescopes—often come as an optical tube assembly only. Telescope mounts come in a bewildering number of varieties to suit everyone’s budget. Since we are confining ourselv
枕垫
发表于 2025-3-24 14:24:35
Our Stellar Universeu’ve chosen your telescope, its accessories and mount and are ready to explore the universe from the comfort of your backyard or your vacation dark sky site. In this part of the book we’ll be exploring the rich milieu of celestial real estate ready for observing. The subjects discussed are rather se
flourish
发表于 2025-3-24 17:07:21
The Spring Galaxiese subject to the relentless grip of gravity, and we’d wind up with a cosmos littered only with black holes. If, on the other hand, the expansion was more rapid, then gravity’s grip would have no teeth, and all we’d see is an amorphous cloud of gas and dust. Only by expanding at its current rate—neit
滑动
发表于 2025-3-24 22:23:49
Sol Invictus some sense ‘common.’ Diligent research across a dozen disciplines has cast severe doubt on that rather outdated and, dare it be said, naive notion. As was touched on in an earlier chapter, our Solar System was forged in a unique epoch in cosmic history, during the time when elements such as uranium
敬礼
发表于 2025-3-25 00:32:30
Our Glorious Moontities of radioactive elements to enrich Earth’s core and ejecting a sizable mass of our planet’s mantle material into orbit around it. The primordial Earth also lost most of its water in this momentous event (it probably had a global ocean some 100 km deep). Over several million years, the ejected