NASA regularly publishes e-Books that are available to download for free. NASA's new e-Book is titled Hubble Focus: The Lives of Stars - about the Hubble Space Telescope. The new ebook offers what NASA says is a “dive deeper into specific topics in astronomy” that the Hubble mission changed.
from /r/books
美国国家航空航天局定期出版电子书,可供免费下载。美国航空航天局的新电子书名为《哈勃聚焦》。恒星的生活 - 关于哈勃太空望远镜。这本新的电子书提供了美国宇航局所说的 "深入研究天文学中的特定主题",哈勃任务改变了这些主题。