Our knowledge of planets like Mars and Jupiter has advanced by leaps and bounds in recent years, but that didn’t just happen as if by magic. Scientists have sent missions to these worlds, like the Juno Jupiter probe and Perseverance Mars rover. But poor Uranus never gets any attention, and a new report from the National Academies of Sciences (NAS) says it’s time that changed. In the group’s Decadal Survey, a Uranus probe is listed as the top priority.
Uranus, in case you are unfamiliar, is the seventh planet, orbiting between Saturn and Neptune. This unassuming blue-gray ball of gas was only visited once — by Voyager 2 in 1986. The spacecraft passed within about 50,000 miles of the cloud tops, but it didn’t spend any appreciable time near the ice giant. NASA leveraged a planetary alignment to send Voyager 2 past Jupiter, Saturn, Uranus, and Neptune — a course known as the Grand Tour.
The NAS has placed the Uranus Orbiter and Probe (UOP) at the very top of its wishlist for the next decade of scientific exploration. This mission would consist of a spacecraft that can remain in orbit of Uranus for several years instead of blasting past on its way out of the solar system. There would also be a probe that can enter the planet’s atmosphere, giving us a better idea of the composition. Currently, scientists believe that Uranus is made up of helium and hydrogen gas, rock, and various types of ice (and it probably smells bad). Our understanding of the ratios and structure of those materials is almost nonexistent, though, which demonstrates the critical need for further study.
So, we have precious little data on Uranus, and that could complicate our study of other solar systems. With the James Webb Space Telescope about to come online, we may finally be able to get a better look at nearby exoplanets, and many of these alien worlds appear to be ice giants like Uranus. If we have a similar planet in our own celestial neighborhood, it would be silly not to take a closer look.
It takes a long time to plan a complex mission like the proposed UOP. The need for a Uranus probe was also noted in the previous Decadal Survey, but it was the number three priority after a Mars mission designed to look for signs of ancient life and a probe to study Jupiter’s moon Europa. We got the Mars mission (Perseverance), and NASA plans to launch the Europa Clipper in a few years to take care of number two. That puts the UOP at the top of the list in the new survey. Hopefully, this will push the agency to take a closer look at Uranus in the coming decade.
The NAS says a Uranus mission could realistically be launched between 2023 and 2032. Other priorities in the report include the need for an Enceladus “Orbilander,” which could examine Saturn’s moon for evidence of life. Like Europa, scientists believe Enceladus has a subsurface ocean, but it regularly releases plumes of water that a landed probe could analyze. We got both of the top recommendations from the last Decadal Survey, so maybe we’ll see both of these missions in the works by 2032.