Illustration of a view over the rim of a small crater, about one kilometer across on Mars Illustration: AFP

The United Arab Emirates said on Wednesday it would delay the launch of its Hope Mars probe for a second time, again due to bad weather.

The probe was originally due to be launched from Japan on Wednesday but had been postponed until Friday for the same reason.

"After extensive meetings, the @UAESpaceAgency and @MBRSpaceCentre, through discussions with Mitsubishi Heavy Industries, announce a further delay of the Mars Hope Probe launch," Dubai's media office tweeted on Wednesday.

It cited "unstable weather conditions at the launch site in Tanegashima Island in Japan" and said a new launch date would be announced within 24 hours.

The UAE is set to be the first Arab nation to send a probe to Mars. The probe is one of three racing to the Red Planet, with Chinese and US rockets also taking advantage of the Earth and Mars being unusually close: a mere hop of 55 million kilometers.

Hope - or Al-Amal in Arabic - is expected to reach Mars's orbit by February 2021, marking the 50th anniversary of the unification of the UAE, an alliance of seven emirates. 

Once there, it will loop the planet for a whole Martian year, or 687 days.

The goal is to provide a comprehensive image of weather dynamics in the Red Planet's atmosphere. 

The probe is expected to detach from the launch rocket about an hour after blast-off,  the UAE Mars mission's deputy project manager Sarah al-Amiri said.