Just when you think humanity has the technology for a thorough probe of Uranus, abnormal winds is forcing scientists to rethink everything we thought we knew about this distant gaseous giant.
New peer-reviewed research published in Nature Astronomy suggests that the atmosphere of the solar system’s seventh planet has “anomalous characteristics” caused by intense solar winds. The information analyzed by astronomers was collected during the 1986 flyby of Voyager 2, humanity’s only probe into the gaseous giant Uranus.
“The data collected about Uranus was a little confusing and didn’t make sense,” said Max Gilbraith, planetarium coordinator for the University of Wyoming. “You could say that the first time we tried to probe Uranus, it was kind of weird, and we're hoping it can be more successful if we try again with this new information.”
If NASA and human civilization want to successfully and scientifically probe Uranus in this century, they’ll need to take this study seriously. Excessive winds or not, Uranus is overdue for its probe, and the best window of opportunity in our lifetimes for a thorough and scientifically sophisticated probe is opening soon.
An Awkward First Time
Voyager 2’s 1986 flyby was humanity’s only mission to delve deeper into the mysteries of Uranus up close and personal. The data it sent back baffled astronomers.
“The data made it appear as though the magnetic pole and the axis of rotation of Uranus were not aligned, even though they should be,” Gilbraith said. “They went back through the data, and it looked like a particular set of circumstances made the magnetosphere of Uranus appear that way.”
The research team discovered that Uranus had undergone “an intense solar wind event” that compressed the planet’s magnetic field shortly before Voyager 2 arrived. Since the frequency of these events is so low, less than 4%, the team concluded that Uranus is probably more similar to the Solar System’s other gas giants than astronomers realized.
The short version, according to the researchers, is that “the unlucky scientists caught Uranus on a particularly gusty day.”
“We've learned how the magnetic fields of gas giants work,” Gilbraith said. “Now, we can use what we’ve learned from Jupiter and Saturn as we go into a new mission to Uranus.”
This is invaluable information for the scientists planning the next generation of planetary exploration. Learning that Uranus was having an unusually strong episode of wind makes the next probing mission less daunting but not less complicated.
Investigating A Windy Uranus
Astronomers don’t underestimate the power of wind, especially potent gusts emanating from the distant Uranus.
“The bigger the planet, the more wind you can have,” said Cowboy State Daily meteorologist Don Day. “It's a whole physics thing with all the gravity, the density of the atmosphere, and all of those things. And from all their observations, Uranus has a lot of wind. Up to 500 mph.”
Wind is one of the many reasons Wyoming doesn’t have a rocket launch pad and likely never will. It’s not rocket science – it’s rocket science.
“I think people take for granted what's needed to launch a rocket safely,” Day said. “They go through all these different layers of the atmosphere with different wind speeds and directions. Conditions must be just right, and the wind can cause a lot of problems. A lot of launches are canceled because of wind.”
Latitude is another critical consideration. Planetary physics for rocket launches is more favorable closer to the equator, which explains why the Kennedy Space Center is located in Florida.
“When you go lower in latitude, you start to get into zones where the natural state of things is to have less wind,” he said. “That's why people who launch rockets tend to do it at those lower latitudes.”
The Uranus Orbiter and Probe will only have to contend with the intense atmosphere of the planet from a distance but will be close enough to learn its secrets. Nevertheless, the potent winds in and around Uranus aren’t to be underestimated.
“If there's an atmosphere, you're going to have wind,” Day said. “It can get really complicated on our planet, let alone Uranus.”
Caustic Cold
Uranus and Neptune are the most distant planets from Earth and remain largely unknown despite their size and importance. Gilbraith said the Uranus Orbiter and Probe would reveal a wealth of knowledge about the seventh planet, making all astronomers giddy about the potential.
“A Uranus mission would be really exciting,” he said. “We could finally understand what’s going on with the atmospheric science of this gas planet, its internal structure, and what sort of cool materials and different molecules might be in Uranus that we don't encounter on Earth.”
Uranus also has an extremely dark ring system and 28 natural satellites. Gilbraith said astronomers suspect many strange things could be happening on the bodies adjacent to Uranus.
“All the gas planets have icy moons around them,” he said. “Uranus’s icy moons could be experiencing gravitational forces differentially stretching and squeezing their surfaces. That creates friction and heat, which creates volcanism or pyrovolcanism, which would be geysers and stuff like that.”
Many astronomers believe there might also be subsurface oceans of water on these moons. That could mean that, of all places, Uranus might be a safe harbor for other life forms in our solar system.
“There could be life in those oceans,” he said. “Critters surviving around geysers on the moons in orbit around Uranus. The mission would allow us to understand Uranus and all the weird things that might be happening out there.”
Patient Probing
A Uranus probe is one of NASA’s highest-priority objectives for the 2030s. The Uranus Orbiter and Probe will study the planet and several of its moons using the same methods as the Galileo and Cassini missions, which studied Jupiter and Saturn, respectively.
There is a plan — and a $4.2 billion budget — to achieve this goal, and time is of the essence. Gilbraith said NASA has a limited window of opportunity to successfully probe Uranus.
“To get a probe from Earth and Uranus, Jupiter and Saturn have to line up to provide a gravitational transfer,” he said. “That will give it the proper oomph to reach Uranus in a reasonable amount of time. You only get that opportunity once every 50 years.”
If the Uranus Orbiter and Probe launch from Earth in 2031 (which is unlikely, according to NASA), it will still take a decade for the payload to reach the planet. The first results of the expensive probing wouldn’t get back to Earth until the 2040s.
Time is running out. If NASA misses the 2032 launch deadline, it won’t have another opportunity to probe Uranus until 2091.
NASA hopes to get its funding request granted in 2025. Assuming they get the funds, the agency would have less than seven years to build and launch the Uranus Orbiter and Probe.
“You need a lot of patience and preparation if you're going to probe Uranus,” Gilbraith said.
Andrew Rossi can be reached at arossi@cowboystatedaily.com.
