In the second half of the 20th century, humankind liberated itself from the shackles of gravity and went into space. By the end of the century its robot emissaries had visited every planet in the solar system: Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune. After running out of planets, space agencies shifted to smaller bodies: asteroids, comets and dwarf planets such as Pluto and Ceres. Now we’ve “exhausted” those, too. Humans want to be first, and the fact is that the 10th robot on Mars isn’t as exciting as the first. Accordingly, in the years ahead we’ll see initial missions to the moons of planets, with the emphasis on the ocean worlds that orbit the outer planets, which are among the leading candidates for the existence of life elsewhere in the solar system.
The decade ahead will also be devoted to the search for life, both simple and intelligent, on exoplanets – planets outside the solar system – with the aid of powerful Earth-based and space-based telescopes. If the rate of expansion of human range and human curiosity in the 20th century are anything to go by, by the middle of this century, humankind will launch a first mission to the neighboring star system, Alpha Centauri.
But space is not the exclusive preserve of robots. We humans, too, deserve to stretch our legs a little and enjoy the spectacular views and the dangers that attend a journey into the expanses of this vast universe. Here, though, our biology enters the picture – and it can’t keep up. So, in the decade ahead we shall see American, Chinese and Indian astronauts, along with regular tourists (not necessarily in that order) returning to, of all places, the moon, a little over 50 years since the first visit there, and the end of the next decade will find astronauts and pioneer settlers on Mars. In fact, the first permanent communities in space will likely be simply in space: in a low satellite orbit around Earth, or in an elliptical orbit around the moon.
2020: Methane on Mars
Because the window of opportunity for launching spacecraft to Mars – which opens biannually – lasts only two weeks, in March 2020 three new rovers (robotic vehicles to explore the surface of other worlds) will be launched to Mars: NASA’s March 2020 (it’s still waiting for a permanent name), Britain’s Rosalind Franklin and, a first, a Chinese rover, HX-1. The rovers will conduct astrobiological experiments in the hope of finding signs of life on Mars, in the past or the present. But none of them will be equipped with sensors capable of solving the most urgent scientific riddle on the red planet: the source of its methane.
Here on Earth, methane gas is emitted primarily by microbes, and the sun’s ultraviolet radiation breaks up the gas relatively quickly. Which is why its seasonal presence in the thin Martian air is surprising. If the source is indeed biological, the phenomenon could be the swan song of bacteria that became extinct on Mars millions of years ago, with the methane they emitted into the depths now slowly being released onto the surface.
According to another scenario, Mars is still pulsing with life in the depths, which thaw with the advent of summer. The European-Russian orbiter ExoMars has been sampling the methane emissions since 2016, so that we can expect to get an answer during the coming year. If it also fails, and the new rovers don’t succeed in finding samples of life on or near the surface, we will just have to wait patiently for initial physical samples from Mars, though they will not reach Earth before the 2030s.
At the same time, the China National Space Administration will launch the first section of what will become, by 2022, a large, manned space station, intended to compete with the International Space Station. The station will be based on the successful experiments of the Chinese with two smaller space stations, Tianzhou-1 and Tianzhou-2, and will provide long-term quarters for up to three taikonauts, as Chinese astronauts are called.
And Elon Musk’s SpaceX company is expected to complete its Starlink project: 12,000 satellites that will net the skies and provide internet to every person in every place on the planet – and to future Mars settlers. Hot Television’s customer service isn’t answering? You’re stuck in a volcanic crater and need to check your frequent flyer miles? Take out a phone and connect to the space-based internet.
2021: James Webb reports
In March 2021, following numberless delays, NASA will at last launch the James Webb Space Telescope, the successor to the Hubble Space Telescope. The new telescope will be launched to Lagrange 2, a relatively stable point between the gravitational forces of Earth and the sun, 1.5 million kilometers from Earth. The advanced space telescope will be able to see galaxies more distant and ancient than anything previously known in history, and even supply us with a first direct photograph of a planet in another star system.
When the present author came into the world, the notion of exoplanets was only a theory. Now we know of 4,000 such worlds, some of them in the habitable zone – at the right distance from their mother star to enable the existence of liquid water on the surface – and of Earth size. After the Kepler and TESS 1 telescopes told us where the planets are “hiding” in the stars’ dazzling light, like coins under a flashlight, the next stage will be to understand what is going on there. “James Webb” – which is named for an early administrator of NASA – will be able to analyze the light refracted from the atmospheres of these planets, and perhaps even to confirm or deny the existence of life in their close proximity. JWST will be the pioneer of photographing the exoplanets, and in the third decade of the 21st century will be replaced by more advanced and more precise telescopes, whose entire purpose will be to analyze closely the reflection of the starsin the skies of foreign worlds.
2022: Juice on the ice
The European Space Agency will launch the Jupiter Icy Moons Explorer (aka JUICE, because every mission needs an acronym). It will explore the giant planet’s icy moons – Europa, Ganymede and Callisto – in order to determine whether they contain an environment that is appropriate for the existence of life as we know it. The three moons are worlds of water possessing an ice envelope. The gravity from gaseous Jupiter warms and nourishes the liquid water below the frozen envelope, and as we know, where there is water, there is life. The moons are considered the best candidates for life in the solar system, along with Mars, of course, and Enceladus and Titan, which are both moons of Saturn. JUICE will only reach Jupiter’s system in 2030, so if you absolutely must know whether there is life on Callisto, you should give up smoking until at least 2033.
NASA will also launch the initial section of the first manned moon-orbiting space station, Lunar Gateway, which will orbit Earth’s satellite elliptically at a distance ranging from 1,500 kilometers to 70,000 kilometers from the lunar surface. The station will serve as a transition point for astronauts and robots on the way to the moon, Mars and Venus. According to the plan, the first manned space ferry will dock at the station in 2024 and will enable the first Americans to make a return trip to the moon. In 2033, the Americans will use the station to refuel a first manned mission to Mars.
On the other hand, NASA’s concept of duty-free in space has drawn heavy flak, with many scientists arguing that the shortest way between two points, such as Earth and the moon, or Earth and Mars, is simply a straight line. At the moment, the expensive program is well-financed, but it’s possible we will see a diversion of budgets in the direction of manned missions to the moon and Mars with a more competitive timetable, especially if the plans of the Indians and the Chinese to launch manned spacecraft prove viable.
2023: First space tourist
SpaceX will launch the first space tourist, the Japanese billionaire and art collector Yusaku Maezawa, who will enter into a lunar orbit.
2024: The race resumes
SpaceX will launch a first manned mission to Mars. In Elon Musk’s vision, the first settlers will arrive on Mars in 2025. Their task will be to prepare a base, and particularly the fuel, for those who will follow. How will it be done? The thin Martian air is rich in carbon dioxide (CO2), and the frozen Martian soil is not lacking in ice (H2O). From them, oxygen (O2) for breathing and methane (CH4) for fuel can be produced. The ultimate vision of SpaceX is a thriving city of a million people, who will travel from Earth to Mars in a thousand flights of 100 passengers each by the end of the 21st century.
Alongside the first manned mission to Mars, the Japan Aerospace Exploration Agency, JAXA, will take advantage of the window of opportunity to send a first expedition to explore the small Mars moons, Phobos and Deimos. The mission, called Martian Moons eXploration, or MMX, will enter into orbit around Mars in 2025 and will land a German-French rover on one of the two moons, to explore its surface. Soil samples will be flown back and reach Earth labs in 2029 – the first samples in history from the Mars system (but not yet the samples we need in order to determine conclusively whether there is or was life on Mars itself).
But 2024 is also zero hour for the new moon race. The United States has announced that it intends to land astronauts on the moon by 2024 as part of the new Artemis program, sister to Apollo. The Indians are hoping to beat the Americans to the punch and land astronauts on the moon as early as 2022. The Chinese, for their part, have stated that they intend to have taikonauts on the moon “in the coming decade.” Nongovernmental players, such as SpaceX and Blue Origin, the latter founded by Amazon owner Jeff Bezos, are also taking part in the new moon race, and have set 2024 as their target year. But they will likely act as NASA subcontractors in this race.
Finally, in 2024, the International Space Station is scheduled to conclude its scientific role when NASA ends its participation in what’s said to be the most expensive project in human history. The station will probably be transferred to commercial companies, for example tourism and pharmaceutical firms. Beyond the terrific fun of floating in microgravity, the low air-pressure conditions in space allow for amazingly rapid experiments with medications, and the pharmacological giants are already ogling the white elephant that’s floating in space. With the lifting of the limitation on profit-generating research studies in space, the International Space Station will become an extremely lucrative business for its founding partners.
2025: Europe’s water
The thermoelectric radioisotope generators in the Voyager 1 and 2 spacecraft, which produce power from radioactive decay, will no longer be able to supply electricity to scientific instruments. The two spacecraft, which were launched in 1977 and were the first to leave the solar system, will continue their interstellar voyage eternally (or until they collide with something), but communication with them will be lost and we won’t hear from them anymore. Go in peace!
In parallel, NASA will launch the Europe Clipper, an orbiter that will map Jupiter’s ice moon. Below the ice covering of about 100 kilometers on Europa lies a global ocean, which is heated above the freezing point by the powerful tides of Jupiter, the gaseous giant. The mission’s purpose will be to find a landing zone for the European Space Agency’s Europa Lander. It will be launched separately in 2025 and will touch down on one of the fault lines of the ice, where it will acquire a direct approach to water and analyze its composition in order to determine whether there is life below the surface whose astonishing smoothness is itself suspicious.
2026 Titan’s methane lakes
NASA will launch the rotorcraft Dragonfly to Titan, Saturn’s singular, intriguing moon. Since Titan’s atmosphere is four times as dense as ours, the eight-rotor drone will not be essentially different from unmanned aircraft that we see on Earth. Dragonfly will reach Saturn’s system in 2034, carry out dozens of flights in Titan’s sky, and land to take samples from a large number of sites, in its search for life on this rich, frozen world.
Titan, the largest of Saturn’s moons, is considered one of the leading candidates for the existence of life in the solar system. It’s the only body in the solar system, with the exception of Earth, of course, on whose surface whole lakes have been found in a liquid state. The lakes on frozen Titan, however, consist not of water but of liquid methane. Here on Earth, all living creatures use water as a solvent (matter that it is capable of dissolving other matter) for their biochemical activity; however, alternative theories of biochemistry maintain that liquid methane can serve as a life-supporting solvent. Will we find methane-based life on Titan?
2028: Interstellar ambush
The European Space Agency will launch Comet Interceptor, a bold mission that will set a space ambush for a comet, asteroid or any other object that will infiltrate from another star system and will map it by means of three separate spacecraft. The mission was planned within the framework of drawing conclusions from the case of Oumuamua, the first object in history positively identified as having come from outside the solar system before passing through it, but which disappeared before it could be investigated. Comet Interceptor’s three spacecraft will lie in ambush at Lagrange 2 for the next interstellar guest, and will be hurtled toward it when it shows up, in the hope of getting a first close-up glimpse of an object that was formed in another star system.
2029: Closest asteroid
On April 13, 2029, the frightening asteroid Apophis will approach to within 31,000 kilometers of Earth – a tenth of the distance to the moon and closer to the ground than some of our manmade satellites. The asteroid, which has a diameter of about 375 meters, is not expected to strike either Earth or the moon, but it will be close enough to be seen even without a telescope, including in the skies above Israel.
2035: America’s choice
NASA will launch the space telescope Habitable Exoplanet Observatory, or HabEx, to Lagrange 2. From there, the telescope will be able to scan thousands of exoplanets in a search for biological and technological signatures in the light reflected from the worlds’ atmospheres, such as a suspicious absorption of water molecules or emission of carbon dioxide. If simple or complex life exists in our neighborhood of the galaxy, HabEx will be able to identify it even where its predecessor, the James Webb Space Telescope, could not.
At the moment, HabEx is in competition with LUVOIR, a more expensive multipurpose telescope, which would be launched in 2039 and be capable of performing other tricks beyond searching for life, such as photographing ancient and remote galaxies from the beginning of the universe. The U.S. National Academy of Sciences and Congress are supposed to choose between these two projects immediately after next year’s presidential election.
2036: Different star system
Breakthrough Starshot, a space initiative of the billionaires Yuri Milner and Mark Zuckerberg and the scientists Stephen Hawking and Avi Loeb, will launch the first of thousands of nano-spacecraft toward the closest star system to us, which is 4.37 light years away. The spacecraft will be accelerated to a speed of about 20 percent of the speed of light by means of Earth-based lasers, and would be expected to reach the triple-star system of Alpha Centauri around 20 years later – in 2056. The images that will be sent back from Alpha Centauri to the solar system will travel at the speed of light and will take four years to reach Earth, taking us to 2060. Members of Gen Y or Gen Z toddlers – you are likely to be the first to feast your eyes on another star system.