Wednesday, February 9 2022 marks one year since the UAE became just the fifth country in the world to reach Mars.
Missions to the Red Planet have a success rate of only 50 per cent, but a year ago today the UAE wrote its name into the record books when the Hope probe spacecraft successfully entered the Martian orbit.
And over the past year the probe has been beaming back images from the Red Planet, revealing a series of stunning landscapes.
Scientists from the University of Colorado Boulder’s Laboratory for Atmospheric Space Physics worked with the Emirati team to help make the mission a reality. They explained some of the key stages of Hope’s journey. Here are five fascinating facts about the mission.
1. The probe is loaded with highly explosive fuel
Where there are rockets, there are massive amounts of explosive liquids. And the Hope probe is no different.
It was loaded with 800 kilograms of hydrazine, a fuel propellant commonly used in spacecraft, for its journey to space.
According to the Royal Chemistry Society, when hydrazine is mixed with oxidising agents, it creates a mixture so explosive that ignition is not needed. Hydrazine decomposes as fuel burns, forming gases that are released from the spacecraft to create thrust.
Hope used half its fuel reserves during the orbit insertion phase on February 9, 2021.
First, engineers rotated the spacecraft so the thrusters pointed in the right direction. Then, Hope’s six thrusters fired to help slow it down from 120,000 kilometres per hour to 18,000kph.
The thrusters were active for 28 minutes – the longest period during this mission – to help adjust Hope’s velocity so it could be captured by Mars’ gravity.
2. Contact was lost with the probe for almost half an hour
Long-distance relationships are difficult, but having no contact at all is worse.
There is a communication delay between mission control and the spacecraft. This is because of the enormous distance between Earth and Mars.
When Hope entered the Mars orbit, it hid behind the planet for 15-20 minutes (called the occultation period), causing all radio signals to be lost - meaning the team did not know they were successful until contact was reestablished.
The occultation stage was a tense period in the mission control room.
3. Hope orbits Mars like a Moon
What sets the UAE’s mission to Mars apart from any other is the special orbit Hope is placed in.
It is at an elliptical orbit between 22,000km and 44,000km from the planet’s surface – the farthest for a spacecraft to date.
Earth’s Moon orbits the planet near to the equator, similarly, Hope’s orbit will be almost parallel with Mars' equator.
The Moon-like orbit helps Hope visit the planet at every time of day.
Previous missions were carried out in highly inclined orbits that were very polar. This limited spacecraft to observing the planet at the same time of day each time.
Hope observes weather patterns and atmospheric conditions at different times of day and night.
Now in orbit, Hope makes a full circle of Mars every 55 hours, far longer than existing spacecraft.
The Mars Reconnaissance Orbiter currently takes 112 minutes to complete the loop, while Trace Gas Orbiter takes 120 minutes and the Maven takes four and a half hours. This is because each are far closer to the surface of the Red Planet.
4. Hope teamed up with another spacecraft while in deep space
In November 2020, Hope and the European Space Agency’s BepiColombo spacecraft each measured distribution of hydrogen in space together.
The European spacecraft was en route to Mercury, and both BepiColombo and Hope's instruments were facing each other so scientists took the opportunity to measure the amount of hydrogen between them.
Scientists from ESA and Mohammed bin Rashid Space Centre worked together to cross calibrate the instruments and get some extra science out of the mission.
Hope was also able to measure interplanetary dust, which is spread throughout space, some particles of which could predate our solar system.
In 2018, researchers in Hawaii found leftover dust from the birth of our solar system preserved in comets.
Studying these tiny particles could help them to learn more about how our planets and Sun formed.
5. Hope's gadgets include camera filters and ‘heat vision goggles’
Hope has three instruments it will use to perform its scientific tasks – an infrared spectrometer, exploration imager and ultraviolet spectrometer.
The exploration imager will take photos of the planet. It will use specific filters to restrict wavelengths of light and capture images that can help scientists learn about things such as ice in the atmosphere, small water ice particles, ozone and dust storms.
The infrared spectrometer will build images of the planet at different infrared wavelengths, almost like fancy heat vision goggles for Mars.
Each pixel could contain key information about the atmosphere, including temperature, water vapour, carbon dioxide, dust and water ice and temperature of the surface of the planet.
The ultraviolet spectrometer will help to make ultraviolet observations of the top of the atmosphere, helping measure particles that may escape from the planet.
