Zond 2

Chronology

Mission timeline

1. November 30, 1964, 13:12 UTC

   Launch

   Launched towards Mars from a Tyazheliy Sputnik in Earth parking orbit

   NSSDCA's launch/orbital information page gives the launch date and time as 1964-11-30T13:12:00Z, recorded here at minute precision because the page prints a whole minute with zero seconds. Zond 2 was launched into a 153 x 219 km Earth parking orbit and then took a long curving trajectory towards Mars to minimize the relative velocity. The same page disagrees with itself and the disagreement is recorded rather than resolved: its Earth-orbit row gives an epoch start of 1964-11-29 13:12:00, one day before the launch date and time printed at the head of the same page and one day before the 30 November 1964 the master catalog prints.

   Earth
2. December 8, 1964

   Milestone

   Ion engines fired, 08-18 December 1964

   The electronic ion engines were successfully tested shortly after launch under real space environment conditions over the period 08-18 December 1964, which NSSDCA records as the first successful firing of ion engines on an interplanetary mission. The spacecraft carried six experimental low-thrust electrojet plasma ion engines that served as actuators of the attitude control system. Recorded at the first day of the period the page publishes.

3. December 15, 1964

   Milestone

   Second solar panel freed by firing the plasma engines

   One of the two solar panels failed due to a broken tug cord, so only half the anticipated power was available to the spacecraft. Controllers were able to finally get the second solar panel to open on 15 December 1964 by firing the plasma engines to shake it free, but this was too late for the crucial first mid-course maneuver.

4. May 1965

   Loss of contact

   Communications lost in early May 1965

   After a putative (but unconfirmed) mid-course maneuver on 17 February 1965, communications with the spacecraft were lost in early May, 1965. Recorded at month precision because the page publishes no day. The same page records a competing account rather than resolving it: some accounts hold that the communications were lost a month or so after launch and no further contact was made with the spacecraft.

5. August 6, 1965

   Flyby

   Passed Mars with no contact

   The spacecraft flew by Mars on 6 August 1965 at a distance of 1500 km and a relative speed of 5.62 km/s. NSSDCA's launch/orbital information page records the same encounter with a closest approach time of 1965-08-06 00:00:00 and a periapsis of 1500.00 km. Recorded at day precision because both pages publish only the date, the trajectory page printing a midnight time rather than an observed one.

   Mars

Mission architecture

Vehicles

• Zond 2 · Spacecraft

  Destinations: Mars