What the next decade of planetary science holds: sky and telescope

What the next decade of planetary science holds: sky and telescope

A planetary vision for the next decade.
National Academies of Sciences

The Planetary Science Community has released a report outlining a vision for the next decade. The decade-long survey, the result of years of steering committees, white papers, advisory groups, and conferences, represents NASA’s (and to some extent NSF’s) marching orders for 10 years of planet and exoplanet exploration.

Decennial survey of planetary sciences and astrobiology by the national academies of the Noble Sciences Origins, worlds and life: a key strategy for planetary sciences and astrobiology 2023-2032It’s the third priority wish list of its kind. As always, any important concept will have to go through funding, design and development rounds before hitting the launch pad.

the last decade

A look at the latest ten-year survey entitled visions and travelsShow the impact these efforts can have. This report was included as a top priority in the Mars Astrobiology and Sample Cache Explorer mission, which has become the persistent rover currently exploring Jezero Crater on the red planet. Perseverance is reserving samples as a first step in the Mars Sample Return initiative, for which the return rover will be launched in the 2026 launch window. The second priority of the decade, the Orbiter mission now called the Europa Clipper, is slated to launch in 2024..

visions and travels It also identified themes for smaller missions, designated by NASA as New Horizons and Discovery-class missions. These themes ultimately led to the selection of Dragonfly, the nuclear-powered helicopter that will fly to Saturn’s moon Titan in 2027, and the Lucia and Spirit asteroid missions, as well as the Da Vinci and Veritas Venus missions that will fly at the end of this one. decade.

This year’s champions

Along with the continued development and support of these projects, the latest decade-long survey prioritizes some great and exciting mission concepts.

as a new top priority main missionwhich by definition has a budget of over a billion dollars, the report recommends Probe and Uranus Probe. This would be a large Cassini-style mission to the ice giant and its moons and would involve a probe entering the atmosphere. So far, we’ve only seen Uranus approaching once, during Voyager 2’s brief flight in 1986. Uranus beat Neptune thanks to the flexibility of current launch vehicles and technology for the 2031-2038 launch window, with Jupiter. to help.

Uranus probe design
A concept design proposal from early 2011 for a potential Uranus mission.
Ten-year NASA / NRC survey

The second highest priority among the flagships is an orbiter and lander that will target Saturn’s moon Enceladus, referred to in the report as Enceladus Orbelander. This moon is a dynamic world with an underground ocean that can hold the complex processes needed to sustain life. Cassini has seen plumes emanating from icy geysers during several close flyovers, and Enceladus Orblander can sample and study the lunar surface up close.

Four other main concepts in the works were the Europa lander, the Mercury lander, the Neptune / Triton mission, and a major mission to Venus.

Orbelander's illustration of Enceladus
Artistic concept of an Orbilander on the surface of Enceladus.

As guiding principles, the survey identified 12 key scientific questions in three main themes: origins, worlds and processes, and life and habitability. These questions, which cover everything from how giant planets formed to whether we will encounter extraterrestrial life, will help fuel mission selection.

“To suspect [the decadal] It’s a very compelling vision for space exploration for the next decade and beyond, “says Jonathan Fortney (University of California, Santa Cruz). I think it’s a great combination for getting new data from some of the hottest and fundamentally new areas. for exploration and reconnaissance “.

The role of minor missions

NASA has two smaller mission classes, New Frontiers offers roughly double the budget for Discovery-class missions but with a slower launch cadence. The selection of New Frontiers 5, treated in the last decade and originally scheduled for October 2022, has been postponed to October 2024.

The new ten-year survey covers the next two rounds, New Frontiers 6 and 7, which will take us through 2032. Rather than recommending specific tasks for these competitive selections, the report presents detailed arguments for consideration:

  • Probe and landing of the Centaur asteroid
  • return the sample ceres
  • Comet surface sample return mission
  • Enceladus mission with multiple flights
  • lunar geophysical network
  • Saturn probe
  • Titan in orbit
  • Triton Ocean World Surveyor (added only for New Frontiers 7)
  • Flower explorer on site

The report does not specify any specific theme for the Discovery program, although it recommends NASA continue to select two Discovery-class missions per round. The report also recommends raising the cost cap for exploration missions from $ 500 million to $ 800 million.

Additionally, the decade also recommends raising the cap, from $ 55 million to $ 80 million, for NASA’s Small Innovative Planetary Exploration Missions (SIMPLEx) and very small, low-cost, high-risk projects.

For our next step to Mars, the report prioritizes Mars Life Explorer as the next mission that will take place after the completion of the Mars sample return.

For lunar exploration, the investigation recommends developing Endurance A, a large champion return mission that will visit the moon’s south pole. It will collect approximately 100 kilograms (220 lbs) of samples, which the astronauts will bring back to Earth as part of the Artemis initiative. The report notes that planetary exploration goals should be primary for Artemis and not a secondary goal.

The report also points to NASA’s need to address the technology funding gap for planetary science missions, which has narrowed to just 4% in recent years. To correct this problem and achieve the goals mentioned in the report, the committee recommends NASA’s Division of Planetary Sciences to increase funding to match previous levels, 6-8% of the total budget.

Budget chart for planetary science.
Project costs in the ten-year survey over time.
National Academies of Sciences

planetary defense

NASA’s planetary defense goals are guided by Brown’s Law, which requires NASA to identify 90% of near-Earth asteroids over 140 meters in diameter by 2020. As of 2021, scientists have ranked only one third of this group. The NEO Surveyor mid-infrared space telescope, already under development, will be instrumental in finding more of these potentially threatened space rocks. Although the upcoming Vera C. Rubin Observatory is a complement to NEO Surveyor, it is not a replacement.

The report also urged NASA’s Office of Orbital Debris Program to work with the US Space Command to discover asteroids very close to Earth. Ground radar and other trackers offer the opportunity to characterize small asteroids near Earth, including the next 99942 Apophis close pass on April 13, 2029. The recent loss of Arecibo makes it necessary to update the tracking and space network. particularly urgent. .

Diversity and equality

Initially, this decade-long survey highlights the urgent need to promote diversity and equity in the planetary sciences. “Ensuring the broadest level of participation is essential for producing high-quality science in an environment of fierce competition for limited human resources,” the report said. “The rich and unprecedented diversity of people in the United States is NASA’s most powerful advantage, but only if this diversity is exploited through robust identification and recruitment procedures … and fair reward structures.”

To this end, the report recommends that NASA’s planetary scientific leadership consider that biases can often be pervasive and unintended and that the agency should work to “remove bias from its actions, wherever they can be found.”

The need for plutonium

The report also highlights plutonium-238 production, resumed in 2013, as crucial for the future of deep space exploration. The radiant energy source will be needed for the Uranus and Enceladus missions, which travel too far from the Sun to use solar panels. The report recommends NASA review plutonium needs for the next generation of missions and increase production if necessary.

Geyser Enceladus
Cassini spies on ice sources on Enceladus.
NASA / JPL / Institute of Space Sciences

Satellites vs asteroids near the Earth

Finally, the report cites the impact that the emergence of satellite constellations, such as SpaceX’s Starlink, UK’s OneWeb, and Amazon’s Project Kuiper, will have on efforts to effectively search for asteroids near Earth. Therefore, the report calls on NASA, the National Science Foundation, and the astronomical community to continue monitoring satellite swarms and investigating ways to mitigate their effects on observations.

The next decade promises exciting years of planetary space exploration. I, for example, can’t wait to see Saturn’s crescent moon above Enceladus’s frozen horizon, not to mention new images of Uranus and its moons. Let’s see, by 2042 I will be. . .