... Comet Animation . ... Comet structures are diverse and very dynamic, but they all develop a surrounding cloud of diffuse material, called a coma, that usually grows in size and brightness as the comet approaches the Sun. ... As comets approach the Sun they develop enormous tails of luminous material that extend for millions of kilometers from the head, away from the Sun. ... The evaporated molecules boil off and carry small solid particles with them, forming the comet's coma of gas and dust. ...

Halley's Comet . Spacecraft that have visited Halley's Comet . ... Then in 1984 and 1985, five spacecraft from the USSR, Japan and Europe were launched to make a rendezvous with Halley's Comet in 1986. ... This image is a mosaic of 8 images taken by the Giotto spacecraft during the Halley encounter on March 13, 1986. ... Courtesy NASA/JPL) . ... Halley's Comets in 1986 . This image of Halley's Comets was taken during its 1986 appearance. ... Cylindrical Map of the Nucleus of Comet Halley . ...

Vega Stamps . International project VEGA was managed by Space Research Institute (IKI) . ... VEGA-1 and VEGA-2 spacecraft were developed by Babakin Space Center and fabricated by Lavochkin Association in Khimki, Moscow region. ... VEGA-1 and VEGA-2 have been the part of the international fleet to Halley's comet, that also included Giotto mission of European Space Agency (ESA) and Sakigake and Suisei by Institute of Space and Aeronautical Science (ISAS) of Japan. ... Vega 1 . ...