Pillinger speculated that higher than expected levels of dust in the Martian atmosphere, which captures heat, caused it to expand and reduce in density, so that the parachutes were not able to slow the probe sufficiently. This would cause the landing to be too hard, damaging or destroying the probe. A number of other failure hypotheses were produced at the time. If the Martian atmosphere was thinner than expected, that would have reduced the parachute's effectiveness and therefore caused the lander to "plummet" and hit the surface with enough speed to destroy it. Turbulence in the atmosphere, which would affect the parachute, was also examined.