Luna E-1A No.1

{{Short description|Soviet space probe (Luna 1959A)}}

{{Infobox spaceflight

| name = E-1A No.1

| image =

| image_caption = An E-1A spacecraft

| mission_type = Lunar impactor

| operator = Soviet space program

| mission_duration = Failed to orbit

| spacecraft_type =

| manufacturer = OKB-1

| dry_mass =

| launch_mass = {{convert|387|kg}}

| power =

| launch_date = {{start-date|18 June 1959, 08:08|timezone=yes}} UTC

| launch_rocket = Luna 8K72 {{nowrap|s/n I1-7}}

| launch_site = Baikonur 1/5

| launch_contractor =

| programme = Luna programme

| previous_mission = Luna 1

| next_mission = Luna 2

}}

Luna E-1A No.1 or E-1 No.5, sometimes identified by NASA as Luna 1959A,{{cite web |url=http://nssdc.gsfc.nasa.gov/planetary/tent_launch.html|title=Tentatively Identified Missions and Launch Failures |website=NASA Space Science Data Coordinated Archive|date=2005-01-06}} was a Soviet spacecraft which was lost in a launch failure in 1959. It was a {{convert|387|kg|adj=on}} Luna E-1A spacecraft, the first of two to be launched.{{cite web|url=http://space.skyrocket.de/doc_sdat/luna_e1a.htm|title=Luna E-1A|last=Krebs|first=Gunter|website=Gunter's Space Page|accessdate=26 July 2010}} It was intended to impact the surface of the Moon, and in doing so would have been the first man-made object to reach its surface.

Launch was originally scheduled for June 16, but delayed two days after a careless lieutenant had the booster filled with the wrong grade of RP-1 propellant. Luna E-1A No.1 was launched at 08:08 UTC on 18 June 1959 atop a Luna 8K72 carrier rocket,{{cite web|url=http://www.astronautix.com/lvs/soyuz.htm |title=Soyuz |last=Wade |first=Mark |website=Encyclopedia Astronautica |accessdate=26 July 2010 |url-status=dead |archiveurl=https://web.archive.org/web/20100107163113/http://astronautix.com/lvs/soyuz.htm |archivedate=7 January 2010 }} flying from Site 1/5 at the Baikonur Cosmodrome.{{cite web|url=http://planet4589.org/space/log/launchlog.txt|title=Launch Log|last=McDowell|first=Jonathan|website=Jonathan's Space Page|accessdate=26 July 2010}} The launch went entirely according to plan through strap-on separation. At T+153 seconds, the yaw gyro failed and the core stage began deviating from its flight trajectory. The AVD system terminated thrust and the booster crashed 841 km (522 miles) downrange.

The spacecraft was intended to conduct experiments during its flight towards the Moon. It would also have released gaseous sodium, in order to create a cloud of the metal which could be observed from Earth, allowing the spacecraft to be tracked.{{cite web|url=http://www.astronautix.com/craft/lunae1a.htm|title=Luna E-1A|last=Wade|first=Mark|website=Encyclopedia Astronautica|accessdate=26 July 2010|url-status=dead|archiveurl=https://web.archive.org/web/20101129192342/http://astronautix.com/craft/lunae1a.htm|archivedate=29 November 2010}} Prior to the release of information about its mission, NASA correctly identified that it had been an attempted lunar impact mission, however they incorrectly believed that it had been launched on 16 June, two days before its actual launch.