With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The Avengers (2012 film) was written by Joss Whedon in 2010.
text_B: The Mars program was a series of unmanned spacecraft launched by the Soviet Union between 1960 and 1973 .. unmanned spacecraft. unmanned spacecraft. Soviet Union. Soviet Union. Mars. Mars. The spacecraft were intended to explore Mars , and included flyby probes , landers and orbiters .. explore. exploration of Mars. Mars. Mars. flyby. planetary flyby. landers. Lander ( spacecraft ). Early Mars spacecraft were small , and launched by Molniya rockets .. Mars. Mars. Molniya. Molniya ( rocket ). Starting with two failures in 1969 , the heavier Proton-K rocket was used to launch larger 5 tonne spacecraft , consisting of an orbiter and a lander to Mars .. Mars. Mars. orbiter. orbiter. Proton-K. Proton-K. The orbiter bus design was likely somewhat rushed into service and immature , considering that it performed very reliably in the Venera variant after 1975 .. orbiter. orbiter. This reliability problem was common to much Soviet space hardware from the late 1960s and early 1970s and was largely corrected with a deliberate policy , implemented in the mid-1970s , of consolidating -LRB- or `` debugging '' -RRB- existing designs rather than introducing new ones .. The names of the `` Mars '' missions do not need to be translated , as the word `` Mars '' is spelled and pronounced approximately the same way in English and Russian .. Mars. Mars. In addition to the Mars program , the Soviet Union also sent a probe to Mars as part of the Zond program ; Zond 2 , however it failed en route .. Soviet Union. Soviet Union. Mars. Mars. Zond program. Zond program. Zond 2. Zond 2. Two more spacecraft were sent during the Phobos program .. Phobos program. Phobos program. In 1996 , Russia launched Mars 96 , its first interplanetary mission since the dissolution of the Soviet Union , however it failed to depart Earth orbit .. Soviet Union. Soviet Union. Mars. Mars. Russia. Russia. Mars 96. Mars 96. dissolution of the Soviet Union. dissolution of the Soviet Union
not_related.