Editing Luna 4 (section)

==Mission==

[[File:Convert ru013.jpg|thumb|300px|left|Postcard commemorating the launch of Luna 4|alt=Postcard commemorating the launch of Luna 4]]

After a development process fraught with technical and jurisdictional delays, the first flight version of the Ye-6 was built in December 1962. Launches on 4 January 1963 ([[Luna E-6 No.2]]) and 3 February 1963 ([[Luna E-6 No.3]]) failed--one was stuck in LEO and another failed to reach orbit.<ref name=ranp3/>{{rp|382-383}}

Luna 4 was launched by a [[Molniya-L]] carrier rocket at 08:16:37 UTC on April 2, 1963. Launch occurred from [[Baikonur Cosmodrome Site 1|Site 1/5]] at the [[Baikonur Cosmodrome]],<ref name=gunter /><ref name=log>{{Cite web|url=https://planet4589.org/space/gcat/data/derived/launchlog.html|title=Launch Log|last=McDowell|first=Jonathan|publisher=Jonathon's Space Report|access-date=25 August 2024}}</ref> and the mission was tracked and controlled from [[Simferopol]], including the {{convert|32|m}} parabolic antenna sited there.<ref name=ranp3/>{{rp|385}} After reaching an initial parking orbit of {{convert|167|by|182|km|mi}}, the rocket's upper stage restarted to place Luna 4 onto a translunar trajectory.<ref name=nssdc/>

Luna 4's initial trajectory was according to plan, but due to a failure of the Yupiter astronavigation system, most likely due to thermal control problems, the spacecraft could not be oriented properly for the planned midcourse correction burn. As a result, Luna 4 missed the Moon by about {{convert|8400|km}} at 13:25 UT on April 5, 1963. It then entered a [[Barycentric coordinates (astronomy)|barycentric]] {{cvt|90000|km}} × {{cvt|700000|km}} Earth orbit.<ref name=nssdc/> 

Although coverage of the flight was front page news outside of the USSR, details released by [[TASS]], the Soviet news agency, were scant.<ref name=timesadvocate>{{cite news|newspaper=Escondido Times-Advocate|date=3 April 1963|title=Russian Moon-Rocket Reaches Half-Way Mark|page=1|url=https://www.newspapers.com/image/568039291/|url-access=subscription}}</ref> This irritated Chertok and his team, who felt the secrecy "belittle[d] the real significance of the space program and generate[d] doubt among the public as to its practicality."<ref name=ranp3/>{{rp|385}}

Despite (and in some ways because of) the relative lack of information, Western scientists were able to deduce much about the Luna 4 (known as "Lunik 4") mission. For instance, logic dictated that the next step after the prior lunar missions would be either a lunar orbiter or a soft-lander. The comparatively long mission length of 3.5 days implied a larger payload, supporting this belief. That Luna 4 missed the Moon, and by a wider margin than [[Luna 1]] and [[Luna 3]], thus suggested a mission failure.<ref name=avweek1963b>{{cite magazine|date=15 April 1963|title=Lunik 4 Believed to Have Failed in Mission|url=http://archive.aviationweek.com/issue/19630415#!&pid=38|magazine=Aviation Week and Space Technology|publisher=McGraw Hill Publishing Company|access-date=23 August 2024|page=38|url-access=subscription}}</ref>

Additional evidence was provided by Radio Moscow's virtual silence regarding the flight as well as the cancellation of the television program "Hitting the Moon", scheduled for 7:45pm Moscow time on April 5, coinciding with Luna 4's arrival at the Moon. A poetry program and a piano interlude were played instead. TASS reports on the probe were uncharacteristically brief, and the last mention of the probe in the newspaper [[Pravda]] was a short reference within a general article on the Moon, which was published April 7.<ref name=avweek1963b/>