<a href="https://en.wikipedia.org/wiki/Sputnik_1" id="mw0Q" rel="mw:WikiLink" title="Sputnik 1">Sputnik 1</a>, the first artificial Earth satellite, launched by the Soviet Union in 1957, falls to <a href="https://en.wikipedia.org/wiki/Earth" id="mw0g" rel="mw:WikiLink" title="Earth">Earth</a> from orbit.<sup about="#mwt133" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-27"}}' id="cite_ref-27" rel="dc:references" typeof="mw:Extension/ref"><a href="./January_4#cite_note-27" id="mw0w" style="counter-reset: mw-Ref 27;"><span class="mw-reflink-text" id="mw1A">[27]</span></a></sup>
<span class="mw-reference-text reference-text" id="mw-reference-text-cite_note-27"><cite about="#mwt130" class="citation book cs1" id="CITEREFAnil_K._MainiVarsha_Agrawal2007">Anil K. Maini; Varsha Agrawal (29 January 2007). <a class="external text" href="https://books.google.com/books?id=Qw7ECiEvy5kC&amp;pg=PA8" id="mwCLc" rel="mw:ExtLink nofollow"><i id="mwCLg">Satellite Technology: Principles and Applications</i></a>. John Wiley &amp; Sons. p.<span id="mwCLk" typeof="mw:Entity"> </span>8. <a class="mw-redirect" href="./ISBN_(identifier)" id="mwCLo" rel="mw:WikiLink" title="ISBN (identifier)">ISBN</a><span id="mwCLs" typeof="mw:Entity"> </span><a href="./Special:BookSources/978-0-470-03335-7" id="mwCLw" rel="mw:WikiLink" title="Special:BookSources/978-0-470-03335-7"><bdi id="mwCL0">978-0-470-03335-7</bdi></a>.</cite><span about="#mwt130" class="Z3988" id="mwCL4" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Satellite+Technology%3A+Principles+and+Applications&amp;rft.pages=8&amp;rft.pub=John+Wiley+%26+Sons&amp;rft.date=2007-01-29&amp;rft.isbn=978-0-470-03335-7&amp;rft.au=Anil+K.+Maini&amp;rft.au=Varsha+Agrawal&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DQw7ECiEvy5kC%26pg%3DPA8&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AJanuary+4"></span></span>