- Three nations have plans to send unmanned missions to Mars in summer 2020: the United States, China, and the United Arab Emirates.
- SpaceX has discussed executing both manned and unmanned Mars missions this decade, though the company describes these dates as "aspirational."
- Each space agency plans to study a different aspect of Mars, though searching for signs of past life is a common theme among the missions.
Putting humans on Mars is the next giant leap in space exploration, yet it remains a far-off goal for national and private space agencies. There's no shortage of complications. With all the economic, technological, and safety hurdles to overcome, some critics say sending manned missions to the Red planet simply doesn't make sense. This thinking explains, in part, why NASA's current long-term strategy is to first return astronauts to the moon in order to "demonstrate capabilities required for human missions to Mars and other destinations."
But that hasn't stopped space agencies from planning unmanned Mars missions for the near future and, more aspirationally, manned missions after that.
Three unmanned Mars missions are set to launch in summer 2020. The timing is no coincidence: Once every two years, Earth and Mars come especially close together because their orbits are "at opposition," which is when the Earth-Mars distance is smallest during the 780-day synodic period. This is an opportune window to send spacecraft to Mars.
As far as a manned mission to Mars? It could happen in the 2020s, but that seems unlikely. But whenever it does, it could mark the beginning of an era where humans live on the Red planet in permanent, large-scale settlements. For example, by 2117, the U.A.E. wants to build a massive Martian city of 600,000 inhabitants, while SpaceX CEO Elon Musk has said that it is "possible to make a self-sustaining city on Mars by 2050, if we start in 5 years & take 10 orbital synchronizations."
For now, three space agencies plan to launch unmanned Mars missions in 2020, while several others hope to launch Martian projects later in the decade.
NASA
This summer, NASA plans to send an unmanned rover to the Red planet for its Mars 2020 mission. A key objective of this mission, which will include deploying a small autonomous helicopter, is to find evidence of extraterrestrial life, not only by "seeking signs of habitable conditions on Mars in the ancient past, but also searching for signs of past microbial life itself," NASA writes on its website.
But the agency doesn't plan to send people to Mars anytime soon. NASA first wants to return humans to the moon, aiming to "land astronauts on the surface no later than the late 2020s." The agency has no official timeline for putting humans on Mars, and a 2019 report suggested the late 2030s is the earliest it could do so.
Mars Exploration Rover – A
As of May 2020, NASA's Curiosity rover is still operational, roaming the martian surface at top speeds of 0.086 mph.
China
In 2019, China successfully landed a rover on the dark side of the moon. This summer, the nation has its sights on an even more ambitious goal: sending an orbiter, lander, and rover to Mars in one trip, something no nation has done before. The mission is called Tianwen-1, meaning "questions to heaven," and its aim is to search for pockets of water below the Martian surface, while also looking for signs of ancient life.
United Arab Emirates
In July 2020, the U.A.E.'s Mohammed bin Rashid Space Centre plans to launch the Hope Mars Mission, which includes a probe that would orbit Mars and study its weather patterns. For the U.A.E., the mission is designed to push the country toward a knowledge-based economy.
"Going to Mars was not the main objective," Omran Sharaf, mission lead for the Hope spacecraft, which is also known as the Emirates Mars Mission, told Space.com. "It's a means for a bigger goal: to expedite the development in our educational sector, academic sector."
The Hope Mars Mission, if successful, would be the first mission to Mars by any West Asian, Arab, or Muslim-majority country.
Japan
In 2024, the Japanese Aerospace Exploration Agency (JAXA) plans to launch a uniquely bold interplanetary mission that will involve sending a probe to orbit Mars, landing on the Martian moon Phobos, collecting surface samples, and then returning those samples to Earth in 2029. JAXA says the mission has two main objectives:
- To investigate whether the Martian moons are captured asteroids or fragments that coalesced after a giant impact with Mars, and to acquire new knowledge on the formation process of Mars and the terrestrial planets.
- To clarify the mechanisms controlling the surface evolution of the Martian moons and Mars, and to gain new insights into the history of the Mars Sphere, including that of the Martian moons.
An improved, color enhanced version of the 360-degree Gallery Pan taken by Mars Pathfinder in 1997.
SpaceX
Elon Musk's aerospace company has its eyes on two Mars voyages: a cargo-only mission in 2022, and a human mission in 2024. The second mission would involve building a propellant depot and preparing a site for future crewed flights. But the company describes these dates as "aspirational." After all, SpaceX plans to use its Starship spacecraft to send Japanese billionaire Yukazu Maezawa and a handful of artists into lunar orbit in 2023. Musk has suggested this trip would be Starship's first mission.
Regarding the long-term future of humans on the Red planet, Musk once told Ars Technica:
"I'll probably be long dead before Mars becomes self-sustaining. But I'd like to at least be around to see a bunch of ships land on Mars."
Russia and the European Union
Roscosmos and the European Space Agency plan to send a Russian lander and a European rover to the Martian surface in 2022 as part of ExoMars. The mission aims to find out if there has ever been life on Mars, and also to understand the history of water on the planet. It's part of a long-term Mars project that began in 2016. This second phase was initially planned for 2020, but due in part to the COVID-19 pandemic, the space agencies decided to postpone the mission by two years.
"We want to make ourselves 100% sure of a successful mission. We cannot allow ourselves any margin of error. More verification activities will ensure a safe trip and the best scientific results on Mars," said ESA Director General Jan Wörner.
India
In 2014, the Indian Space Research Organization executed its first interplanetary trip with its Mars Orbiter Mission. It marked the first time an Asian nation reached Martian orbit, and also the first time a nation successfully reached the Red planet on its maiden voyage. India has plans for a follow-up Mars Orbiter Mission 2, but it remains unclear when that will occur, and what the mission will entail. Some reports suggest the mission will include a rover and lander, in addition to an orbiter.
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Reactive oxygen species (ROS) accumulate in the gut of sleep-deprived fruit flies, one (left), seven (center) and ten (right) days without sleep.
- A study provides further confirmation that a prolonged lack of sleep can result in early mortality.
- Surprisingly, the direct cause seems to be a buildup of Reactive Oxygen Species in the gut produced by sleeplessness.
- When the buildup is neutralized, a normal lifespan is restored.
We don't have to tell you what it feels like when you don't get enough sleep. A night or two of that can be miserable; long-term sleeplessness is out-and-out debilitating. Though we know from personal experience that we need sleep — our cognitive, metabolic, cardiovascular, and immune functioning depend on it — a lack of it does more than just make you feel like you want to die. It can actually kill you, according to study of rats published in 1989. But why?
A new study answers that question, and in an unexpected way. It appears that the sleeplessness/death connection has nothing to do with the brain or nervous system as many have assumed — it happens in your gut. Equally amazing, the study's authors were able to reverse the ill effects with antioxidants.
The study, from researchers at Harvard Medical School (HMS), is published in the journal Cell.
An unexpected culprit
The new research examines the mechanisms at play in sleep-deprived fruit flies and in mice — long-term sleep-deprivation experiments with humans are considered ethically iffy.
What the scientists found is that death from sleep deprivation is always preceded by a buildup of Reactive Oxygen Species (ROS) in the gut. These are not, as their name implies, living organisms. ROS are reactive molecules that are part of the immune system's response to invading microbes, and recent research suggests they're paradoxically key players in normal cell signal transduction and cell cycling as well. However, having an excess of ROS leads to oxidative stress, which is linked to "macromolecular damage and is implicated in various disease states such as atherosclerosis, diabetes, cancer, neurodegeneration, and aging." To prevent this, cellular defenses typically maintain a balance between ROS production and removal.
"We took an unbiased approach and searched throughout the body for indicators of damage from sleep deprivation," says senior study author Dragana Rogulja, admitting, "We were surprised to find it was the gut that plays a key role in causing death." The accumulation occurred in both sleep-deprived fruit flies and mice.
"Even more surprising," Rogulja recalls, "we found that premature death could be prevented. Each morning, we would all gather around to look at the flies, with disbelief to be honest. What we saw is that every time we could neutralize ROS in the gut, we could rescue the flies." Fruit flies given any of 11 antioxidant compounds — including melatonin, lipoic acid and NAD — that neutralize ROS buildups remained active and lived a normal length of time in spite of sleep deprivation. (The researchers note that these antioxidants did not extend the lifespans of non-sleep deprived control subjects.)
Image source: Tomasz Klejdysz/Shutterstock/Big Think
The experiments
The study's tests were managed by co-first authors Alexandra Vaccaro and Yosef Kaplan Dor, both research fellows at HMS.
You may wonder how you compel a fruit fly to sleep, or for that matter, how you keep one awake. The researchers ascertained that fruit flies doze off in response to being shaken, and thus were the control subjects induced to snooze in their individual, warmed tubes. Each subject occupied its own 29 °C (84F) tube.
For their sleepless cohort, fruit flies were genetically manipulated to express a heat-sensitive protein in specific neurons. These neurons are known to suppress sleep, and did so — the fruit flies' activity levels, or lack thereof, were tracked using infrared beams.
Starting at Day 10 of sleep deprivation, fruit flies began dying, with all of them dead by Day 20. Control flies lived up to 40 days.
The scientists sought out markers that would indicate cell damage in their sleepless subjects. They saw no difference in brain tissue and elsewhere between the well-rested and sleep-deprived fruit flies, with the exception of one fruit fly.
However, in the guts of sleep-deprived fruit flies was a massive accumulation of ROS, which peaked around Day 10. Says Vaccaro, "We found that sleep-deprived flies were dying at the same pace, every time, and when we looked at markers of cell damage and death, the one tissue that really stood out was the gut." She adds, "I remember when we did the first experiment, you could immediately tell under the microscope that there was a striking difference. That almost never happens in lab research."
The experiments were repeated with mice who were gently kept awake for five days. Again, ROS built up over time in their small and large intestines but nowhere else.
As noted above, the administering of antioxidants alleviated the effect of the ROS buildup. In addition, flies that were modified to overproduce gut antioxidant enzymes were found to be immune to the damaging effects of sleep deprivation.
The research leaves some important questions unanswered. Says Kaplan Dor, "We still don't know why sleep loss causes ROS accumulation in the gut, and why this is lethal." He hypothesizes, "Sleep deprivation could directly affect the gut, but the trigger may also originate in the brain. Similarly, death could be due to damage in the gut or because high levels of ROS have systemic effects, or some combination of these."
The HMS researchers are now investigating the chemical pathways by which sleep-deprivation triggers the ROS buildup, and the means by which the ROS wreak cell havoc.
"We need to understand the biology of how sleep deprivation damages the body so that we can find ways to prevent this harm," says Rogulja.
Referring to the value of this study to humans, she notes,"So many of us are chronically sleep deprived. Even if we know staying up late every night is bad, we still do it. We believe we've identified a central issue that, when eliminated, allows for survival without sleep, at least in fruit flies."
