Mission control in Dubai has uploaded its final commands into the Hope probe before the spacecraft tries to enter Mars’ orbit on Tuesday.
The probe will carry out procedures autonomously so it is captured by the Red Planet’s gravity.
Engineers at mission control say they are feeling anxious but confident as the mission’s most complex stage approaches.
With only a 50 per cent success rate, there is no guarantee the orbit entry attempt will succeed.
The National explains the automated sequence Hope will perform on February 9.
Start those thrusters
At 7.30pm Gulf Standard Time, the Mars orbit insertion process will begin. The spacecraft will fire its six Delta V thrusters to slow itself down from 120,000 kilometres per hour to 18,000kph. The deceleration is essential for entering orbit, or it will miss its opportunity.
There is a communication delay of 11 minutes between Hope and mission control, so engineers will not know until 7.42pm whether the burn has begun.
The engines will fire for 27 minutes. When the burn ends, at 7.57pm, the spacecraft will have, hopefully, entered Martian orbit.
But the signal confirming entry should be received at mission control by 8.08pm.
Loss of signal
If mission control do not receive the signal, it means Hope has moved behind Mars and communication has been lost.
That temporary blackout period, known as occultation, could last between 15 and 20 minutes.
Prior to signal loss, and despite the communication delay, mission control could still be monitoring the progress of the burn, giving at least a slight indication of the spacecraft’s health.
But a full evaluation can be made only after communication is restored.
What are the risks?
There are three pairs of thrusters. If one pair fails, the spacecraft is programmed to automatically readjust and keep going.
If any more malfunction, the mission will fail.
The thrusters have been used throughout Hope’s journey to Mars to correct its course but this will be the first time they are used for that long.
Hope was loaded with 800 kilograms of hydrazine fuel, half of which will be used during orbit insertion.
Where is the spacecraft now?
Hope began its journey on July 20, 2020, when it was launched from Tanegashima Space Centre, Japan.
Of the 493.5 million kilometres it is meant to travel, Hope has less than 3.38 million kilometres remaining until it reaches Mars.
It will use gravity to slingshot itself around the planet and be captured in its orbit.
Where can I watch Hope reach Mars?
It will be streamed live on the Emirates Mars Mission website.