Data will be provided by an experiment aboard the Mars Express spacecraft, which is making its final orbital adjustments around Mars after being captured by the Red Planet's gravity last month.

Scientists will transmit a precise radio signal to the orbiter, which will then send the signal back when it loops around the planet and is almost exactly aligned with Earth.

By passing through the thin Martian atmosphere on its trip home, the signal undergoes subtle changes that, when transcribed, give details as to atmospheric temperature, density and pressure.

The experiment will undergo a test run Tuesday and if everything works well, should be able to produce the "first Martian weather report" in April, a service that should run for the next four years, an ESA press statement said.

By terrestrial standards, Martian weather forecasts will be unremittingly bleak.

The planet has an atmosphere that is mainly carbon dioxide, is frequently gripped by fierce dust storms and its temperatures are often chill enough to freeze blood.

SPACE.WIRE