Vega 2 - The Halley Mission

The Halley Mission

After their encounters, the Vegas' motherships were redirected by Venus' gravity to intercept Halley's Comet.

The spacecraft initiated its encounter on March 7, 1986 by taking 100 photos of the comet from a distance of 14 million kilometers.

Vega 2 made its closest approach at 07:20 UT on March 9, 1986 at 8,030 km. The data intensive examination of the comet covered only the three hours around closest approach. They were intended to measure the physical parameters of the nucleus, such as dimensions, shape, temperature and surface properties, as well as to study the structure and dynamics of the coma, the gas composition close to the nucleus, the dust particles' composition and mass distribution as functions of distance to the nucleus and the cometary-solar wind interaction.

During the encounter, Vega 2 took 700 images of the comet, with better resolution than those from the twin Vega 1, partly due to the presence of less dust outside of the coma at the time. Yet Vega 2 recorded an 80% power loss during the encounter as compared to Vega 1's 40%.

After further imaging sessions on 10 and 11 March 1986, Vega 2 finished its primary mission. Vega 1 ran out of attitude control propellant on 30 January 1987, and contact with Vega 2 continued until 24 March 1987.

Vega 2 is currently in heliocentric orbit.