The world's tallest building lit up briefly with a countdown timer as the UAE prepared to launch its Hope probe on its mission to Mars.
Red lights were beamed on to Burj Khalifa on Sunday as the world awaited the lift-off on July 15.
The launch will take place at 12.51am UAE time on Wednesday.
People can watch the event streamed live on the official mission website.
The live stream is available in English and Arabic, and can be viewed with or without commentary.
The mission remains on schedule, and several weather checks will be carried out in advance to ensure a smooth lift-off.
Latest updates showed the probe, which is inside the payload fairing, is in the process of being mounted on top of the rocket.
The rocket will be rolled out to the launch pad soon in an operation lasting up to 40 minutes to protect it and the craft from possible damage.
Sarah Al Amiri, president of the UAE Space Agency and deputy project manager of the mission, confirmed that all systems were "go" for the launch on Wednesday.
“The spacecraft is ready for launch and all of the systems are now at a level that is ready to be launched,” said Ms Al Amiri, also the UAE Minister of State for Advanced Science.
“We also checked the ground segment and the operations in mission control and they are ready to accept the spacecraft after launch.
“The final checks are currently ongoing on both the launch vehicle and mission control. We are ready to launch as scheduled early in the morning of July 15.”
The carrier rocket with Hope aboard will blast off from Japan and the probe is intended to be the first to provide a complete picture of the Martian atmosphere when it reaches the planet's orbit in 2021.
Data collected will help to answer questions about the planet, with studies of its lower and upper atmosphere.
The project has been in the works since 2014 and cost Dh735 million ($200m), from concept to design, construction and launch.
Final launch preparations under way for UAE Mars Mission
