Despite the failure of the 1M Mars probes, the Soviet engineers continued the development on the 1V probes that were to land a small camera equipped probe on the surface of Venus. During the fall of 1960, as the launch of the 1M were attempted, it was realized that the atmospheric descent probe could not have been ready for the launch window, which opened on January 15, 1961 and closed exactly one month later. It was thus decided to cancel the lander and re-use as many components of the 1M as possible. In this second version the probe became known as 1VA. It was of course a quite similar spacecraft to 1M, having a different mission and payload. On board of the probe, whose total mass was 643.5 kg, were mounted scientific instruments for studying the interplanetary magnetic fields, cosmic rays, plasmas and interplanetary dust. The objective of the three probes, this time, was to fly by the planet or, with some luck, attempt impact with it. For this reason, each of the probes carried in the place of the 1M photographic system, a spherical module inside which was a 70 cm commemorative terrestrial globe made of emailed metal and designed to float in a possible venusian ocean and a medallion inscribed with the emblem of the USSR and the mission of the probe. The spacecraft also carried a technological experiment for which some different material was exposed to the rigors of vacuum to study its degradation.
For 1VA a very critical problem was of course the uncertainties in the ephemeris of Venus which, aggravated by its particular position in the Solar System, amounted to some hundred thousand kilometers (more than fifteen times the planet's radius!).
The first 1VA was launched on February 4, 1961. This time Block I worked just as designed but a component of the Block L ullage rocket electric ignition system broke down and it became impossible for the probe to leave Earth orbit. The complex of the probe and Block L stage was named "Heavy Sputnik" and re-entered in the Earth's atmosphere some 22 days later.
The second 1VA was launched on February 12 and received the name Venera-1 when, after one hour in parking orbit, the Molniya Block L stage fired and sent it in a solar orbit (1.019 AU aphelion, 0.718 AU perihelion and 0.58 degrees of inclination) that would have taken it to fly-by Venus from a distance of 100000 km on May 19, after 96 days of flight and after sweeping an angle of 120 degrees. This meant of course that the probe was using a type I interplanetary transfer orbit.
The Crimean Yevpatoria deep space communication antenna received the telemetry of the probe a few hours after launch and first noticed a series of problems that could endanger the whole mission: the thermal control system was about to malfunction and the attitude control system had broken, so that all communication had to use the low gain antenna as the high gain one was not aimed toward the Earth. On February 17 the probe was contacted for the second time, while 1.7 million km from Earth.
The third communication session, on February 22, never happened. The Soviets asked the 76 meters Jordell Bank British radiotelescope to try to receive telemetry from the probe as it had on previous occasions. On March 4 the antenna tried to track the probe for three hours, and on March 5 for seven hours, to no avail. Finally, on the day of the fly-by, some command was sent to the probe by the Soviets, while Jordell Bank was busy listening for an answer. Some three signals were received by Jordell Bank but all of them proved to be terrestrial in origin. A last attempt to communicate with the probe was made on June 10.
Venera-1 thus became the first man made probe to fly-by another planet but it never sent back any data on Venus. A failure analysis later determined that the unpressurized Sun sensor used some non vacuum qualified component, so that the spacecraft lost attitude control as soon as it went into space.
As for the 1M, the third 1VA was never launched.
The year 1961 was a very important one for Venus studies anyway. On April 9, in fact, the planet passed trough inferior conjunction (i.e. it went approximately between the Earth and the Sun) and for the first time American and Soviet scientists were successful in bouncing electromagnetic waves on its surface and collecting their echo. It was thus possible to measure with the uncertainty of just 500 km the length of the Astronomical Unit (149,598,500 km), to improve the ephemeris of the planet and to discover its very slow and retrograde rotation.

Bibliography
Gatland, K. W.: Spacecraft and Boosters, London, Illife Books, pp. 9-18
Lardier, C.: L'Astronautique Sovietique, Paris, Armand Colin, pp. 117-118 (in French)
NSSDC Master Catalog: Venera-1 entry
Semenov, Yu. P.: Roketno-Kosmicheskaya Korporatsiya Energhiya; Moscow, RKK Energhiya, pp. 141-142 (in Russian)
Varfolomeyev, T.: Soviet Rocketry that Conquered Space, Part 4; Spaceflight, January 1998, pp. 28-30
Varfolomeyev, T.: Soviet Rocketry that Conquered Space, Part 5; Spaceflight, March 1998, pp. 85-88
Victor, W. K.: The First Real Time Contact with Venus; PASP, Vol. 73, No. 434, p. 338. (this article is available on line on NASA Astrophysic Data System)

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