Every 18 to 24 months, Earth and Mars align in such a way as to make deep-space travel that little bit easier, or at least a bit faster. That reduces a trip or "trajectory" to the Red Planet from about nine months down to seven.
That means that July is shaping up to be a very busy time for missions to Mars.
There are three all launching within days of each other — the Emirates Mars Mission, with its atmospheric probe, Hope or "Al-Amal," NASA's Mars 2020, carrying a lander called Perseverance, and China's "Tianwen-1", a collection of orbiters and landers. In fact, there would have been a fourth mission in Europe's ExoMars 2020.
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"If they don't go know, they will have a very long wait," says Malcolm Macdonald, a professor of space technology at the University of Strathclyde, Glasgow. "That's why the Americans, for instance, through the current pandemic, prioritized Demo-2, the SpaceX crewed mission to the International Space Station, and their Mars mission."
How the coronavirus pandemic has affected the Chinese mission is hard to know. And Europe's ExoMars 2020 was already heading for delays.
As for the Emirates Mars Mission (EMM), failing to leave now would set a 100-year plan for national — and interplanetary — transformation back by two years. So, after a round of ultra-fast thinking, which predicted the lockdown and those closed international borders, the team dispatched its spacecraft, Hope, and a team of Emirati engineers for the launch in Japan before it was too late.
A sense of urgency
There is a sense of urgency in the UAE that harks back to when the nation was established in 1971, starting from a point where infrastructure like transport and education were underdeveloped.
It was "evident then that you needed to do things rapidly to get on a par with the world," says Sarah Al-Amiri, the EMM's Science Lead, in an interview with DW.
And you can see that in the way the EMM has grown. The UAE has been developing Earth Observation spacecraft since 2006, which is a short time in itself. But the Mars mission has gone from a feasibility study in 2013 to its announcement a year later, and now a launch in 2020. Six short years.
"We don't have a hundred years to sit around and grow organically. It's always been that way, developing in leaps and bounds," says Al-Amiri.
That culture of rapid growth has been hastened by a dwindling demand for oil.
"There is a drive to diversify," she says. "And the way to do that is use today's oil, which is knowledge and expertise that's routed in science and technology."
For Al-Amiri and mission manager, Omran Sharaf, seeing UAE's space sector blossom is a long-held passion. They were perhaps among the more fortunate, being able to study abroad. But they are back and among the country's pioneers.
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Al-Amir says she "never dared to dream of space, just for a lack of existing opportunities" at home, but she had started programming by the 5th Grade at school, studied computer engineering, and is now UAE's Minister of State for Advanced Sciences.
Meanwhile, Sharaf says he was always curious about satellites — "I wished I could work on a space program." He studied electrical engineering in the US, came back to the UAE and joined a team of young Emiratis charged with setting up that space program. They started gathering experience in South Korea, working on Earth observation satellites, DubaiSat-1 and 2.
Why not the moon?
It's not only about getting to space. The mission is designed to establish the UAE's space capabilities — to encourage homegrown innovation and inspire new generations of scientists, with job prospects and a sustainable future.
As such, it's reasonable to ask, "Why not go to the moon?" It is closer after all.
The answer lies in the science.
"We're not underestimating the moon — it's difficult, too. Getting there is not easy," says Sharaf, in the same interview. "But Mars is the next level. When it comes to the scientific questions and the purpose of exploring Mars, we can build a better rationale behind it. It's a planet that scientists believe was once alive and became a dead planet. Understanding what happened there and why it lost its atmosphere will help us understand our own planet."
Mars is an active area of research that relies on data collected "at the planet," says Al-Amiri, rather than via telescopes and other forms of observation. So, she says, the EMM will deliver data that is actually needed by the global science community.
The team has collaborated with universities in the US and UK, and they have consulted the NASA-affiliated Mars Exploration Program Analysis Group (MEPAG).
MEPAG is a gathering of experts that publishes scientific "vision papers," detailing scientific goals and questions that need to be answered about the planet.
Key scientific objectives for Hope
The Hope Probe aims to be the first to provide a complete picture of the Martian atmosphere. It will try to explain why or how Mars loses hydrogen and oxygen gases into space over the span of a Martian year.
Significantly, Hope will explore Mars' "diurnal," or day-to-night cycle, which has never been done before.
Using three instruments — an ultraviolet spectrometer, a digital camera and an infrared spectrometer, they will overlay images to create a picture from the lower to upper atmosphere. But Hope's orbit will be central to getting the data they want.
As François Forget, an astrophysicist at the Laboratoire de Météorologie Dynamique in Paris, France, puts it: "The instruments are not revolutionary, but the orbit is completely new."
A new Martian orbit
"Mars rotates, like Earth, but in 24 hours and 38 minutes, and the spacecraft will have an elliptical orbit of about 20,000 kilometers at its lowest to 43,000 kilometers at the top," says Forget, who is also involved in the Emirates Mars Mission.
"When it's at 20,000 km, it will stay above the same [location on Mars], rotating with the planet for 8 hours and that will let us monitor what's going on throughout the day — so, for instance, we'll see morning fog disappearing here, a storm start there," says Forget, "— and then it will move up again, and when it's higher, the spacecraft moves slower, while the planet keeps rotating below it. When it returns to the lowest altitude, it will rotate with the planet again. So, we'll see what's happening over time."
With each swing of the orbit, Hope will track different locations — from its lower and higher orbits. In the end, all the data will be stitched together to make a complete picture of those locations over a full 24-hour period, day and night. But it may take three orbits of a particular location to accumulate a full diurnal cycle, says Forget.
Weather patterns and dust storms
There are so many questions to answer and no single mission can answer them all.
But, ultimately, scientists want to know how Mars became uninhabitable for humans, why its atmosphere wouldn't protect us like the atmosphere on Earth.
Mars' atmosphere is thin like Earth's, but it mostly consists of carbon dioxide (CO2), and there's only a small amount of oxygen and water vapor. So, finding out more about why that little oxygen — which humans need to live and breathe — escapes Mars is crucial to our understanding of the planet.
"MEPAG has set questions for the community, things we need to learn to understand Mars' evolution, and one of those things is historical atmospheric change," says Al-Amiri. "That's understanding the weather system, the day-to-night cycle, and the dynamics there — what are the seasonal changes?"
Or why Mars gets global dust storms. "We get localized, regional dust storms. But Mars gets global dust storms. So, what factors allow a planet to be engulfed by a single dust storm," asks Al-Amiri.
What role does Mars play in its own atmospheric loss?
Then there's the specific question of why the planet is losing its atmosphere.
Scientists have looked at whether that's due to space itself — for instance, that the atmosphere is being "stripped" by solar winds — streams of charged particles that shoot out from the sun at speeds of up to 900 km per second.
But some other theories suggest Mars may play its own role.
"There are dust storms, cloud formations, water vapor cycles, and we're asking how much impact that has on the loss of hydrogen and oxygen from Mars into its exosphere," says Al-Amiri.
The mission will do that by taking simultaneous measurements — infrared technology in the lower atmosphere, where Hope will study temperatures and ice clouds, and ultraviolet technology for the Martian ozone in the lower atmosphere and hydrogen and oxygen loss in the upper atmosphere.
Finally, there's a simple camera that will enable Hope to take full "disc images" of the planet, which may reveal "interesting phenomena," says Forget.
"For example, a couple of years ago, we found these elongate clouds forming near the top of Olympus Mons [the largest volcano on Mars]. They went for 2,000 kilometers, and this had never been seen, because we were always looking at Mars in strips from the same local time," says Forget. "So, a full disc image can be spectacular, fun and scientific."
Mission to collaborate
Much has been made of the mission's launching from Japan. But the Japanese space agency, JAXA, points out that the mission is "UAE's independent program."
But the Japanese connection is interesting to note because Japan has its own interests in Mars.
In an email to DW, JAXA's Nobuyoshi Fujimoto writes that Japan's MMX mission in 2024 will "survey Mars's two moons and collect a sample from one of them and bring it back."
There is also a good chance that data from the Emirates Mars Mission will flow into Japan's MMX moons mission.
"The Japanese have got fantastic capabilities, but they've never been to Mars," says Macdonald, "so, working as partners in the international community will give them more confidence for the next time they decide to go."
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The EMM is all about international collaboration, which, Sharaf says, has been good with American teams at the University of Colorado Boulder, Arizona State University, and University of California, Berkeley.
"Getting some of the knowledge for our mission was not easy and we had to think about how it could be done in a way that serves everyone — our national interests, that of our partners, and humanity," says Sharaf. "So, this is a case study from which other nations can learn. For instance, how we collaborated in 2006 with Korea — a very different mindset and system — and in 2014 with the US."
That collaborative spirit will possibly also seep into other areas of research as the UAE moves towards a "post-oil" economy.
"Our space program is a tool for other goals," says Sharaf. "It's linked to national challenges like food and water, and clean energy is an issue, but also economic opportunities. Those are the pillars that dictate our program. It's not just about getting to space. So, if asteroid mining or rocket fuel addressed one of those pillars, we would look into it."
All that's left…
The only question that's left for now is whether the UAE and its first Mars mission will succeed.
"Going to Mars is difficult, not a lot of people have successfully gone to Mars," says Macdonald. "The Americans, Europe, Russia and India have orbited it. But Russia's had a lot of failures trying to land on Mars, and the Japanese have failed before."
So, what are the UAE's chances?
"Well, the launch vehicle tends to be a fairly big stumbling block, but the Japanese have a good heritage there, so you'd expect the launch to work and for the spacecraft to get to Mars," Macdonald says. "And as long as it wakes up and gets onto its correct trajectory… But you can't expect success, because space is difficult."