The Luna programme is one of the most successful programmes in space exploration. It included a series of robotic spacecraft missions that were aimed at the moon by the Soviet Union in the period between 1959 and 1976.
Designed as orbiters or landers, 15 missions were successful in this programme, accomplishing a series of firsts in our foray towards the moon. It all started with Luna 1, which became the first human-made object to reach escape velocity – the speed and direction required to travel beyond the Earth’s gravity.
Renamed later
The probe that we now call Luna 1 was originally referred to, along with its launch vehicle, as Cosmic Rocket by the Soviet Press. It was only in 1963 that it was retroactively renamed as Luna 1.
Luna 1 was a sphere-shaped spacecraft with five antennae extending out of one of its hemispheres. It had no propulsion systems on itself and instrument ports protruded from the surface of the sphere.
The three-stage launch vehicle was launched on January 2, 1959 and the launch vehicle enabled its third stage to accelerate beyond 11.2 km per second – enough to leave the Earth’s gravitational field. Luna 1 separated from its third stage after reaching escape velocity on the same day, thereby becoming the first human-made object to escape the confines of Earth’s gravity.
Gas cloud
On January 3, a large cloud of sodium gas was released by the spacecraft at about 1,30,000 km from the Earth. The glowing orange trail of gas was visible over the Indian Ocean with the brightness of a sixth-magnitude star, meaning it was just visible to the unaided eye under favourable conditions.
As it panned out, bad weather conditions prevented observations of the gas at most sites. It was, however, captured on film in one of the ground stations and was also photographed by astronomers. Even though the “artificial comet” proved to be a poor aid in tracking the mission, it served as an experiment to study the behaviour of gas in space.
A problem with the guidance system of Luna 1 meant that the spacecraft did not follow the planned trajectory. It was later understood that a two-degree error in pointing of a ground-based radio-control antenna during the powered flight of the rocket gave the spacecraft more velocity than was required. As a result, the spacecraft was now set to cross the lunar path before the moon could pull it into its gravitational field.
Achieves lunar flyby
On January 4, 34 hours after the launch, Luna 1 passed about 6,400 km from the moon’s surface. While it failed to meet its primary objective of impacting the lunar surface, its increased velocity meant that it became the first human-made object to go into orbit around the sun. Luna 1 went into orbit around the sun between the orbits of Earth and Mars, thereby becoming the first artificial planet of the solar system.
Even though ground controllers lost contact with Luna 1 approximately 62 hours after launch, the spacecraft had provided considerable data by then. The measurements obtained from the mission provided data on Earth’s radiation belt, showed that the moon had no magnetic field and that a solar wind streamed through interplanetary space. Despite not meeting its objective, the other successes of Luna 1 prompted further missions that eventually made the Luna programme extremely successful.
Published - January 02, 2022 12:05 am IST
