The solar system is overflowing with fascinating destinations, but NASA can only operate a few missions.
So every 10 years, the agency asks scientists to assess the state of planetary science and determine which issues should be top priorities for the scientific community. Led by the National Academies of Science, Engineering and Medicine, this massive undertaking is dubbed a decennial survey – and the latest report is now public, offering a tantalizing look at what space enthusiasts can expect in the next decade.
“This report presents an ambitious but actionable vision for advancing the frontiers of planetary science, astrobiology and planetary defense over the next decade,” said Robin Canup, planetary scientist at the Southwest Research Institute and co-chair of the ten-year research steering committee, said in one demonstration. “This recommended portfolio of missions, high-priority research activities and technology development will yield transformative advances in human knowledge and understanding of the origin and evolution of the solar system, and of life and the habitability of other bodies beyond. Earth.”
Committee members will speak about the report during a press conference held on Tuesday (April 19) at 2pm EDT (1800 GMT), which you can watch live by the National Academy.
Related: Our solar system: a photographic tour of the planets
Scientists began work on this new decennial survey in late 2019. The process included half a dozen committees, each meeting at least 20 times and informed by a total of 527 white papers submitted by scientists from around the world. The resulting document is 780 pages long and comes just a few months after the publication of a Similar document for the field of astronomy and astrophysics.
the magnitude of the report means that scientists and administrators will pore over their findings for months, but some of the report’s initial conclusions are clear.
A fundamental duty of decadal research is to prioritize missions for NASA, including the largest missions, called flagships. The agency’s two current flagship missions, recommended by research from the previous decade, are the $2.7 billion Mars Rover Perseverance that landed on the Red Planet last year and the $4.25 billion Europe Clipper mission scheduled to launch in 2024.
For the new report, the committee evaluated six potential flagship projects across the solar system, from a spacecraft to landing on Mercury for a mission that would explore so much Neptune and its largest moon, Triton.
Of these proposed flagship missions, the committee determined that NASA’s top priority should be the development of a flagship-class mission for Uranus – what could be a $4 billion venture. A combination of factors pushed the concept of a Uranus orbiter and probe to the top spot, including the scientific potential offered by finally taking a close look at the so-called “ice giant” and the feasibility of the mission.
The mission would launch in 2031 or 2032, spend about 13 years walking to its target, then orbit Uranus for several years, examining its atmosphere, interior, rings and moons.
“Uranus itself is one of the most intriguing bodies in the solar system,” the committee members wrote in the document. In addition, the committee emphasized that finally developing a mission dedicated to one of the ice giants — Uranus or its neighbor, Neptune — was a vital priority, but noted that the logistics of a mission to Neptune during the years in question were challenging.
If NASA receives funding strong enough to carry out a second main mission before the next 10-year survey launches in 2032, the committee recommended that the mission be called Orbilander Enceladus, a perhaps $5 billion spacecraft that would orbit and land on Saturn’s tiny icy moon. This mission would orbit the moon for about 1.5 years, then spend two years working on its surface, analyzing scoops of the icy material.
Planetary science at home and abroad
With eight planets, more than 200 moons and countless smaller objects roaming the solar system, planetary scientists face a rich buffet of exploration opportunities. But a key thread running through the new decade is to consider planetary science not just in our own celestial neighborhood, but also in the context of alien worlds.
This is not surprising: in 2012, when the last decade was published, scientists identified fewer than 1,000 confirmed exoplanets beyond our solar system; today, that number exceeds 5,000. In the years since, astronomers have also worked to understand the ways in which our solar system may be representative – or not – of other planetary systems.
In fact, the science of exoplanets is one of the main reasons the Decennial research team cited it for prioritizing a flagship mission to Uranus. “Exoplanets with similar masses are perhaps the most abundant class of exoplanets and a class of planet inherently different from gas-rich Jupiter and Saturn,” the scientists wrote.
The decade highlights three major themes as the most pressing scientific questions for planetary scientists to address in the next decade: origins (“How did the solar system and Earth originate, and are systems like ours common or rare in the universe?”), worlds and processes (“How did planetary bodies evolve from their primordial states into the diverse objects seen today?”) and life and habitability (“What conditions led to habitable environments and the emergence of life on Earth, and life formed in other places?”) .
These questions are big when considering the potential destinations the committee has endorsed for middle-class missions. These options include a geophysical network in the moonsample return missions to a comet or dwarf planet Ceres and a variety of spaceships bound for Saturn or its moons Titan and Enceladus.
But while the decennial survey is based on general thinking, it also includes a clear focus on Earth. For the first time, the document includes a section on the state of the profession, assessing social and structural issues facing planetary scientists, such as implicit and systemic bias and the low representation of people from marginalized groups in the field.
Here, the committee emphasized the importance of strengthening systems for collecting and analyzing evidence on the real situation of these issues. The decade also endorsed a system called anonymous double peer review, which scientists now use to allocate time on the Hubble and James Webb Space Telescopes. The system eliminates the lead scientist’s name from proposals that leave committees to award observations based on proposed science alone.
“While scientific understanding is the primary motivation for what our community does, we must also work to boldly address issues concerning our community’s most important resource – the people who drive its science and planetary exploration missions,” Philip Christensen, Arizona State University planetary scientist and co-chair of the steering committee, said. “Ensuring broad access and participation in the field is essential to maximize scientific excellence and safeguard the country’s continued leadership in space exploration.”
One second new section covered planetary defense, a growing area of focus for NASA that involves identifying, tracking, and assessing the risk to Earth posed by asteroids in our vicinity. The agency already has research programs to detect these asteroids and is working to build a new spacecraft, called the NEO Surveyor, to identify these near-Earth objects, all of which have been endorsed by the decade.
In addition, the 10-year survey requires NASA to make use of the 2029 flyby of the large asteroid Apophis. During this encounter, the asteroid will definitely not collide with Earth, but such a close flyby of such a large asteroid offers scientists a unique opportunity to practice planetary defense and study any changes the flyby causes to the asteroid itself.
The planetary defense program launched its first dedicated mission, the Double Asteroid Redirection Test (DART) last autumn; this year, the spacecraft will collide with an asteroid’s moon to test humans’ ability to move a menacing asteroid out of Earth’s danger zone. Following this mission and the NEO Surveyor mission, the ten-year survey notes that NASA’s next priority should be to launch a rapid-response spacecraft to explore a nearby asteroid, a sort of dress rehearsal for disaster.