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NASA advisers call for a visit to Uranus, plus more science during moon landings

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A probe that will land on Saturn's moon Enceladus, seen here in false color, is one of the priorities outlined in the new report. NASA/JPL/Space Science Institute hide caption

A probe that will land on Saturn's moon Enceladus, seen here in false color, is one of the priorities outlined in the new report.

A robotic mission to orbit Uranus. A probe that can land on a potentially life-supporting moon of Saturn. And a better plan for astronauts to do high-quality science on the moon.

These are among the top priorities outlined in a new report from an influential group that's advising NASA on where to boldly go in the next decade, from 2023 to 2032.

Every ten years, the prestigious National Academies of Sciences, Engineering, and Medicine brings together committees of space experts to survey the field of planetary science and reach a consensus on the best way for NASA to explore strange new worlds.

Some of the items on their latest wishlist sound familiar, but others are brand new. And while the report paints an optimistic picture of the field overall, there are hints of concern about future budget constraints.

NASA wants to bring home pristine Martian rock samples that a rover has gathered; this artist's conception shows one plan for getting them off the red planet. NASA/JPL-Caltech hide caption

NASA wants to bring home pristine Martian rock samples that a rover has gathered; this artist's conception shows one plan for getting them off the red planet.

Retrieving Mars rocks is "highest scientific priority"

The last time around, in 2011, expert advisers told NASA to gather an interesting selection of rocks on Mars and then work to bring those pristine samples back to Earth for chemical analyses. This could show whether the red planet ever had life. They also argued for a mission to Europa, a moon of Jupiter that seems to have an ocean of water beneath its icy surface.

NASA embraced those goals and has been making progress, but planetary scientists have started to worry that cost overruns might threaten the ability to visit other places in the solar system that beckon.

"Right now in planetary science in the U.S., we're at record levels of funding," says Casey Dreier , senior space policy adviser for The Planetary Society, a nonprofit that promotes space exploration. "But I think at the same time, we are being squeezed by two major missions, Mars Sample Return and Europa Clipper."

Bringing home rocks from the red planet should remain "the highest scientific priority of NASA's robotic exploration efforts this decade," according to the new, 780-page report on the expert group's findings.

"The committee strongly supports Mars sample return. It's a concept that's been around a long time, it has a great deal of scientific validity and support," steering committee co-chair Philip Christensen of Arizona State University told NPR.

But the report also says if the price tag looks to rise substantially above $5.3 billion, or if the cost eats up more than around 35% of NASA's planetary science budget in any given year, NASA should seek additional money from Congress rather than taking funds away from other worthy missions — like ones to Uranus and Enceladus.

In 1986, NASA's Voyager 2 probe flew by Uranus, seen here in an image from the Hubble Space Telescope. NASA/Space Telescope Science Institute hide caption

Ice giants could hold surprises

A trip to Uranus could help scientists understand ice giants.

Unlike rocky planets like Mars and gas giants like Jupiter, the ice giants Uranus and Neptune have never been studied with a dedicated mission to orbit and study them.

Uranus, the seventh planet from the Sun, has only ever been visited by NASA's Voyager 2 probe, which flew by in 1986, coming within about 50,000 miles.

In recent years, detections of planets in alien solar systems show that ice giant planets are "likely the most common class of planets in the universe," says Robin Canup of the Southwest Research Institute, who co-chaired the steering committee. "We saw this mission as delivering absolutely transformative, breakthrough science because we know so little about these systems. We are sure there are going to be lots of surprises once we get there."

An ocean world could have evidence of life

Enceladus, one of Saturn's moons, is another scientifically compelling destination.

It's thought to have an ocean of liquid water under an icy crust, just like Europa, but this moon sends plumes of that material out into space, making it easier to obtain samples that originated deep within. The new report recommends sending a probe that could arrive there in the early 2050's, land on the surface and search for evidence of life in fresh plume material that rains down on it.

"Enceladus is the logical candidate to go to try to look for evidence of life today," says Christensen. "In terms of the ocean worlds, it's by far the most active and the easiest to access."

Making it to the moon again

The advisers say NASA needs to get serious about doing science in its multi-billion effort to return astronauts to the moon, called the Artemis program.

They point out that the failure to do this so far means the scientific return of the astronauts' initial trips "will not be as significant as it could be, and may be minimal."

"We see the Artemis program as being aspirational and transformative, and we want it to be accompanied by transformative science," says Canup.

But the group found there's a lack of organization and accountability at NASA for working high-priority science into the planning for moon landings. Planetary exploration has been done for decades with robots, and it's separated from human spaceflight within the agency's organizational structure.

"Let's do great science at the moon," says Christensen, and bring "the robotic and the human sides of NASA together into a really strong partnership."

Protecting earth and other priorities

The report runs through a bevy of smaller missions around the solar system that have merit, such as visits to the dwarf planet Ceres and to Titan, the largest moon of Saturn.

And it gives a notable shout-out to the effort to protect Earth from potentially hazardous space rocks.

NASA should "fully support" a telescope , called the Near-Earth Object Surveyor, which is designed to search for these dangerous rocks, the report says. That telescope has recently faced budget cuts and delays.

"Protecting Earth is important," says Bethany Ehlmann , a planetary scientist at Caltech who served on the report's steering committee, "and we can achieve good science while doing it."

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• giant planet

Remember Uranus?

You know, the seventh planet from the sun? It could use some attention.

Let’s get it out of the way now. Any comments that might come to mind when you hear the name of the seventh planet from the sun pronounced a certain way—keep them to yourself. No giggles. Absolutely no wisecracks—damn it. No jokes! This is an earnest story about Uranus.

Because this is a big day for Uranus. Once every decade, NASA asks the National Academies of Science, Engineering, and Medicine to bring a bunch of planetary scientists together to decide on the country’s priorities for future missions in the solar system. And the latest report , released today, has put this outer planet front and center. According to the powers that be, the top priority for the next decade of space exploration is spending several billion dollars on a shiny, new flagship mission to Uranus.

Uranus deserves a closer look. Only one spacecraft, Voyager 2, has ever visited the planet, and that was in 1986, with technology developed in the ’70s. The visit was short; Uranus was one stop on the mission’s grand tour of the solar system , and the probe made its observations while on the move. What scientists are recommending now is a mission designed specifically to study everything about the Uranian system, including the planet, its moons, and its rings—yes, Uranus has rings!

Given our history of lowbrow humor with Uranus—which is pronounced Yoor -uh-nus, by the way—one might assume that we’re pretty familiar with our cosmic neighbor. But even with the best space telescopes, it’s difficult to study a planet that is twice as far from Earth as is Saturn, and much smaller than the ringed planet. Although we know more about the universe than ever before, we still don’t understand one of the planets in our very own solar system.

Read: The many mysteries of Uranus

Name any aspect of the Uranian system, and planetary scientists can give you a list of unanswered questions about it. Scientists suspect that Uranus, like Neptune, is made of different kinds of ice, gases, and rock, but they can’t say anything for sure about the composition of its hazy atmosphere or the structure of its interior. Unlike the other planets, Uranus spins on its side, which means summers of constant sunlight and winters of complete darkness; it was probably knocked over by a giant impact many eons ago, but what kind? Planetary scientists have no idea how its magnetic field works, and they really love knowing how magnetic fields work. Those rings—what are they made of? And Uranus’s moons—could some of them have subsurface oceans? The imagery from Voyager showed the sideways planet as a mostly featureless, bluish orb , but telescope observations in the past two decades have captured intriguing bursts of cloud activity in its atmosphere. What’s that all about?

The Uranus mission—if NASA decides to take the space-science community’s suggestion—would mean putting a spacecraft in orbit around the planet, and even dropping a probe into its atmosphere. With Voyager, “it’s almost like if you drove by a person and had a few seconds to look at them,” Jonathan Fortney, an astronomer at UC Santa Cruz, told me. “Do you feel like you’d have a good understanding of who they were?” A spacecraft in residence, by contrast, is akin to “spending years talking to them and getting to know their idiosyncrasies,” he said.

By getting to know Uranus, planetary scientists can learn about a class of planets called ice giants. The space community is already quite familiar with the workings of the terrestrial planets in our solar system, such as Earth and Mars, and NASA is already lining up new missions to Venus. Scientists also have a good handle on Saturn and Jupiter, our gas giants, thanks to dedicated missions that spent years orbiting those planets. But Uranus and Neptune, the ice giants? Those pages in our cosmic understanding are nearly blank.

Read: The most overhyped planet in the galaxy

Which is particularly frustrating for scientists, because ice giants might be one of the most common planets in the galaxy. Research on exoplanets—planets beyond our solar system—has shown that gas giants like Saturn and Jupiter are rare, but worlds about the size of Uranus and Neptune are everywhere . So before anyone can understand the ice giants out there, scientists should examine more closely one of our own. Planetary scientists picked Uranus over Neptune for practical reasons; Neptune, which since 2006 has had the distinction of being the outermost planet in our solar system (well, depending on whom you ask ), is farther. “They’re both absolutely compelling, and they’re not identical,” Amy Simon, a planetary scientist at NASA who studies the ice giants, told me. For example, Uranus, even though it’s closer to the sun, is actually colder than Neptune—and, you guessed it, scientists don’t know why that is, either. But with the rocket systems currently in operation, Uranus is easier to reach .

Any mission to the outer planets still takes quite a bit of time. If a Uranus mission were to launch in 2031, the earliest opportunity suggested by the National Academies report, it wouldn’t reach the planet until the end of that decade. Any later, and the spacecraft would arrive in the 2040s. But planetary scientists are used to playing the long game, Heidi Hammel, an astronomer at the Association of Universities for Research in Astronomy, told me. Hammel worked on the Voyager mission during the Uranus flyby, and by the time this new mission reaches its target, “I’ll be watching from the front porch of the retired-planetary-scientist old-age home,” she joked. Maybe NASA would let her totter into mission control, she said, to watch a new generation of researchers bask in the experience. She knows how wonderful it is to see a world come into view in real time. And she and her colleagues caught only a glimpse of Uranus 36 years ago. This time, if NASA indeed makes a dedicated Uranus mission a priority, humanity can stick around for a while. “I guarantee that when we get there,” Hammel said, “the young scientists working on this are going to see things that they never even imagined.”

NASA really wants to probe Uranus and could start planning next year

But we probably won't reach the planet until the 2040s.

We still have so much to learn about our cosmic neighborhood.

There's no doubt that we've learned a lot about our solar system over the past six and a half decades of spaceflight, but there are still mysteries lurking around every corner. One of the biggest ones is the planet Uranus . Other than a brief flyby by NASA's Voyager 2 spacecraft in 1986, we haven't visited the planet at all.

But that's soon going to change. According to this year's decadal survey by the National Academies of Sciences, Engineering, and Medicine, a flagship orbiter and probe mission to Uranus should be NASA's main planetary science project of the next decade. (A decadal survey is report that polls the scientific community on top research priorities — it's prepared every 10 years.) At a virtual town hall on Aug. 18, Dr. Lori Glaze, director of NASA's Planetary Science Division, announced a very rough timeline for the potential Uranus mission.

Related: Uranus by 2049: Here's why scientists want NASA to send a flagship mission to the strange planet

"We are working towards initiating ... some studies of a Uranus orbiter probe mission no later than fiscal year 2024. We will explore a range of complexity and cost options as part of those studies," she said, later adding that the studies could even commence as early as fiscal year 2023.

The Uranus Orbiter and Probe (UOP) , as this mission concept is known, would see a spacecraft spend several years orbiting the ice giant, with a potential probe making a dive down through Uranus' atmosphere . Not only would this research enhance our knowledge of the planet itself, but it could also give us insight into the evolution of ice giant systems, which are found throughout our galaxy .

Such flagship missions, of course, take plenty of research and planning — the UOP is still just a concept and not a mission quite yet. The kickoff in FY 2024 would simply be the early phases of research to figure out the potential shape of the mission. "We need to make sure that we are putting in place a mission that can be implemented and executed," said Glaze.

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 — Shades of Uranus: Scientists know why the planet and Neptune are different hues of blue — Uranus is belching X-rays and is weirder than we ever thought — Yes, there is really 'diamond rain' on Uranus and Neptune  

Though there's no formal timeline yet, Glaze did indicate that a launch could happen as soon as the early 2030s, which would place the spacecraft's arrival at Uranus sometime in the 2040s or beyond. It will take anywhere from 12 to 15 years for it to traverse the nearly 2 billion miles (3.2 billion kilometers) between Earth and Uranus.

"I think it's fantastic now that we have very clear guidance from the decadal survey on the highest priority next flagship, and the fact that they've specifically identified Uranus as the ice giant to visit," said Glaze. "We're really excited about this."

Follow Stefanie Waldek on Twitter @StefanieWaldek . Follow us on Twitter @Spacedotcom and on Facebook .

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Space.com contributing writer Stefanie Waldek is a self-taught space nerd and aviation geek who is passionate about all things spaceflight and astronomy. With a background in travel and design journalism, as well as a Bachelor of Arts degree from New York University, she specializes in the budding space tourism industry and Earth-based astrotourism. In her free time, you can find her watching rocket launches or looking up at the stars, wondering what is out there. Learn more about her work at www.stefaniewaldek.com .

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Journey to the mystery planet: why Uranus is the new target for space exploration

The last time a probe visited the distant ice giant was in 1986, yet learning more about this cold world could tell us a lot about the galaxy

O n the night of 13 March 1781, William Herschel was peering through his telescope in his back garden in New King Street, Bath, when he noticed an unusual faint object near the star Zeta Tauri. He observed it for several nights and noted that it was moving slowly against background stars. The astronomer first thought he had found a comet but later identified it, correctly, as a distant planet. Subsequently named Uranus , it was the first planet to be discovered since antiquity. The achievement earned Herschel membership of the Royal Society, a knighthood and enduring astronomical fame.

Studies have since shown Uranus to be a very odd world. While the rest of the planets in our solar system spin like tops, Uranus lies on its side. And although it is not the farthest planet from the sun, it is the solar system’s coldest.

Uranus also endures seasons of extraordinary magnitude. Each pole spends decades bathed in non-stop sunlight, before experiencing decades of total darkness. A human being who was born at sunset near the pole disappearing into autumn darkness, would have to wait 42 years to see their first spring sunrise. For good measure, Uranus is the only planet to be named after a Greek rather than a Roman god. (Uranus was the grandfather of Zeus.)

Despite these astronomical oddities and extremes, surprisingly little effort has been made to get up close to Uranus. Only one robot probe has ever visited it – in 1986 – when the US Voyager 2 craft swept past on its grand tour of the solar system. It revealed a massive, featureless, pale blue world with an atmosphere of hydrogen, helium and methane, a rich family of moons and a powerful magnetic field. And that has been that.

Such slight regard is about to change, however. Earlier this year, the US National Academy of Sciences published a report that urged Nasa to launch a Uranus probe as its highest-priority flagship mission for the next decade. The academy publishes a report on US priorities in planetary exploration every 10 years and each decadal survey carries enormous clout – which means Nasa is now under enormous pressure to design and fund such a mission.

For their part, Uranus enthusiasts are delighted. “It is tremendous news,” says planetary scientist Prof Leigh Fletcher, of Leicester University. “There are few places left in the solar system about which we know less than we do about Uranus. The inner planets have been visited many times by probes and so have Jupiter and Saturn. Even tiny, distant Pluto has been surveyed. So a Uranus mission will fill a glaring gap in our knowledge of the processes that shaped our solar system.”

Astronomers divide the sun’s planets into three basic categories. There are Mercury, Venus, Earth and Mars, the rocky inner planets that orbit near the sun. Then, further out there are the gas giants Jupiter and Saturn, huge worlds made mostly of hydrogen and helium. Finally, at the edge of the solar system, there is Uranus and its partner Neptune , respectively the second most distant, and the most distant planet from the sun. These two are called ice giants because they are massive (though not as big as Jupiter and Saturn) and because they are formed from icy material. Crucially, they have high abundances of methane, water and other ice-forming molecules in their atmospheres and interiors. (Beyond these worlds lies Pluto, which was formally declassified as a planet and recategorised as a dwarf planet by the International Astronomical Union in 2006.)

These features were always considered interesting though not sufficiently intriguing to deserve special attention – until astronomers began to study worlds around other stars and found ice giants like Uranus and Neptune were everywhere. “It is really intriguing: when we look at planets around other stars, we find a great many of them are similar to Uranus and Neptune,” adds Fletcher. Or as Jonathan Fortney, a planetary scientist at the University of California Santa Cruz, puts it: “Nature loves to make planets of this size.”

Just why ice giants are widespread in our galaxy is unclear. “However, there is obviously something important about planets like Uranus and Neptune,” says Fletcher. “And crucially we have two great examples of them, the galaxy’s most common planets, right here in our solar system. Yet their composition, their nature, and their origins remain a relative mystery. It is time to put that right.”

Correcting this planetary omission will not be easy, however. Uranus orbits the sun at an average distance of 1.8bn miles (2.8bn km); Neptune at 2.8bn miles (4.5bn km). The former’s relative proximity to Earth therefore makes it the favoured target. Nevertheless, a Uranus mission will still need help reaching its target – in the form of a gravity assist from Jupiter. This sort of manoeuvre has been used on other missions in our solar system and involves a spacecraft sweeping low over a planet that lies on its route. The capsule gains energy from this close encounter and so can carry more instruments and fuel than would otherwise be possible. A rendezvous with Jupiter would therefore result in a Uranus probe that, with more fuel on board, could explore Uranus for longer with a more sophisticated suite of instruments.

But timing is tight. Celestial mechanics dictate that a Uranus mission will have to be launched in 2031 or 2032 to reach Jupiter at the right time to exploit it for a gravity assist. This leaves Nasa with a decade to design the probe, raise the $4bn (£3.3bn) or more that will be needed to build it, complete its construction and then launch it on its 13-year voyage. Given these pressures, and the widespread interest in exploring the ice giants, the project will almost certainly involve the participation of other organisations, such as the European Space Agency .

Most ideas for the mission envisage a main craft that would orbit Uranus, survey the planet while occasionally swinging near some of the its moons and rings for close inspection. A companion probe could also be dropped into the Uranian atmosphere to study its composition.

Apart from finding evidence that might explain why ice giants are common around other stars, the mission would aim to solve many other mysteries about Uranus. Why is the planet so cold, and why is its axis of rotation tilted sideways, almost into the plane of its orbit round the sun, a phenomenon that means its north and south poles lie where most other planets have their equators?

“One theory is that a very large object – a huge asteroid perhaps – hit Uranus some time in the past and knocked it over,” says physicist Prof Patrick Irwin of Oxford University. “Such an event would also explain another strange feature about Uranus: it appears to have almost no internal heat left over from its formation – making it the coldest planet in the solar system.

“Jupiter, Saturn and even Neptune still have some internal heat and emit more energy into space than they gather from the sun. But not Uranus. All its internal heat seems to have disappeared, possibly because that huge impact turned it inside out so that its hot internal contents ended up on the outside and its heat quickly radiated away into space. We need a probe to resolve issues like these.”

It remains to be seen if Nasa can act quickly enough to build and launch a mission as complex as the one needed to study Uranus. Many astronomers are nervous about the tightness of the timetable – although there is one ray of light. In 2011, the National Academy of Sciences published its last decadal survey and urged Nasa that for the next 10 years it should concentrate first on a mission to Mars to start collecting rocks for return to Earth, and second on a probe that would be sent to Europa, the icy moon of Jupiter, to see if it might harbour life. A decade later, the US robot rover Perseverance has already begun the former task, while Nasa’s Europa Clipper is to launch in 2024. “That shows these deadlines can be met and that gives us hope,” says Fletcher.

It remains to be seen how plans for the Uranus mission fare – though there is one intriguing coda to the story of the planet’s selection as a prime destination. As its secondary candidate for a flagship mission over the next 10 years, the National Academy of Sciences has recommended that a spacecraft should be sent to Enceladus. This tiny moon of Saturn behaves in a startling manner. It spews organic-rich plumes of water into space, making it an ideal candidate for sampling in order to search for microbes or other primitive forms of life that might exist on the little moon.

A mission to Enceladus shares many of the complexities that bedevil plans for any mission to a distant gas or ice giant. However, it is also united in a remarkable way to the proposed probe to Uranus. Enceladus was discovered in 1789 – by no less a figure than William Herschel.

Herschel’s discovery remembered

A commemorative stone will be unveiled next month in the garden of 19 New King Street, Bath, to mark the exact spot where William Herschel rested his homemade telescope and first glimpsed Uranus. The event – on 25 August – will form a key part of celebrations, which began this weekend, to mark the 200th anniversary of the death of the German-born astronomer.

Herschel died on 25 August 1822, and the new exhibition at his home – now the Herschel Museum of Astronomy – will include his observation book in which he wrote notes from the night when he first observed Uranus. Also on show will be a catalogue of stars recorded by his sister Caroline, a professional astronomer in her own right, a prolific discoverer of comets, and the first woman to receive a salary as a scientist.

William Herschel was also a gifted musician and could play the oboe, violin, harpsichord and organ and composed numerous concertos and symphonies. His scientific achievements include the first detection of infrared radiation; the observation that the pole caps of Mars vary seasonally; and the later discovery of previously unobserved moons around Saturn.

However, the discovery of Uranus remains his main claim to fame. Intriguingly, Herschel originally wanted to name it after his patron, King George III, which would have made it Georgium Sidus, or George’s Star. However, the moniker was not widely liked outside England and eventually the name Uranus was agreed – although it did not get full international acceptance until the middle of the 19th century.

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• 03 March 2020

Destination Uranus! Rare chance to reach ice giants excites scientists

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Momentum is building among planetary scientists to send a major mission to Uranus or Neptune — the most distant and least explored planets in the Solar System. Huge gaps remain in scientists’ knowledge of the blueish planets, known as the ice giants, which have been visited only once by a spacecraft. But the pressure is on to organize a mission in the next decade, because scientists want to take advantage of an approaching planetary alignment that would significantly cut travel time.

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The seventh planet from the Sun with the third largest diameter in our solar system, Uranus is very cold and windy. The ice giant is surrounded by 13 faint rings and 27 small moons as it rotates at a nearly 90-degree angle from the plane of its orbit. This unique tilt makes Uranus appear to spin sideways, orbiting the Sun like a rolling ball.

The first planet found with the aid of a telescope, Uranus was discovered in 1781 by astronomer William Herschel, although he originally thought it was either a comet or a star. It was two years later that the object was universally accepted as a new planet, in part because of observations by astronomer Johann Elert Bode.

William Herschel tried unsuccessfully to name his discovery Georgium Sidus after King George III. Instead, the planet was named for Uranus, the Greek god of the sky, as suggested by Johann Bode.

Potential for Life

Uranus' environment is not conducive to life as we know it. The temperatures, pressures, and materials that characterize this planet are most likely too extreme and volatile for organisms to adapt to.

Size and Distance

With a radius of 15,759.2 miles (25,362 kilometers), Uranus is 4 times wider than Earth. If Earth was the size of a nickel, Uranus would be about as big as a softball.

From an average distance of 1.8 billion miles (2.9 billion kilometers), Uranus is 19.8 astronomical units away from the Sun. One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this distance, it takes sunlight 2 hours and 40 minutes to travel from the Sun to Uranus.

Orbit and Rotation

One day on Uranus takes about 17 hours (the time it takes for Uranus to rotate or spin once). And Uranus makes a complete orbit around the Sun (a year in Uranian time) in about 84 Earth years (30,687 Earth days).

Uranus is the only planet whose equator is nearly at a right angle to its orbit, with a tilt of 97.77 degrees – possibly the result of a collision with an Earth-sized object long ago. This unique tilt causes the most extreme seasons in the solar system. For nearly a quarter of each Uranian year, the Sun shines directly over each pole, plunging the other half of the planet into a 21-year-long, dark winter.

Uranus is also one of just two planets that rotate in the opposite direction than most of the planets (Venus is the other one), from east to west.

Uranus has 27 known moons. While most of the satellites orbiting other planets take their names from Greek or Roman mythology, Uranus' moons are unique in being named for characters from the works of William Shakespeare and Alexander Pope.

All of Uranus' inner moons appear to be roughly half water ice and half rock. The composition of the outer moons remains unknown, but they are likely captured asteroids.

Uranus has two sets of rings. The inner system of nine rings consists mostly of narrow, dark grey rings. There are two outer rings: the innermost one is reddish like dusty rings elsewhere in the solar system, and the outer ring is blue like Saturn's E ring.

In order of increasing distance from the planet, the rings are called Zeta, 6, 5, 4, Alpha, Beta, Eta, Gamma, Delta, Lambda, Epsilon, Nu, and Mu. Some of the larger rings are surrounded by belts of fine dust.

Uranus took shape when the rest of the solar system formed about 4.5 billion years ago – when gravity pulled swirling gas and dust in to become this ice giant. Like its neighbor Neptune, Uranus likely formed closer to the Sun and moved to the outer solar system about 4 billion years ago, where it is the seventh planet from the Sun.

Uranus is one of two ice giants in the outer solar system (the other is Neptune). Most (80% or more) of the planet's mass is made up of a hot dense fluid of "icy" materials – water, methane, and ammonia – above a small rocky core. Near the core, it heats up to 9,000 degrees Fahrenheit (4,982 degrees Celsius).

Uranus is slightly larger in diameter than its neighbor Neptune, yet smaller in mass. It is the second least dense planet; Saturn is the least dense of all.

Uranus gets its blue-green color from methane gas in the atmosphere. Sunlight passes through the atmosphere and is reflected back out by Uranus' cloud tops. Methane gas absorbs the red portion of the light, resulting in a blue-green color.

As an ice giant, Uranus doesn’t have a true surface. The planet is mostly swirling fluids. While a spacecraft would have nowhere to land on Uranus, it wouldn’t be able to fly through its atmosphere unscathed either. The extreme pressures and temperatures would destroy a metal spacecraft.

Uranus' atmosphere is mostly hydrogen and helium, with a small amount of methane and traces of water and ammonia. The methane gives Uranus its signature blue color.

While Voyager 2 saw only a few discrete clouds, a Great Dark Spot, and a small dark spot during its flyby in 1986 – more recent observations reveal that Uranus exhibits dynamic clouds as it approaches equinox, including rapidly changing bright features.

Uranus' planetary atmosphere, with a minimum temperature of 49K (-224.2 degrees Celsius) makes it even colder than Neptune in some places.

Wind speeds can reach up to 560 miles per hour (900 kilometers per hour) on Uranus. Winds are retrograde at the equator, blowing in the reverse direction of the planet’s rotation. But closer to the poles, winds shift to a prograde direction, flowing with Uranus' rotation.

Magnetosphere

Uranus has an unusual, irregularly shaped magnetosphere. Magnetic fields are typically in alignment with a planet's rotation, but Uranus' magnetic field is tipped over: the magnetic axis is tilted nearly 60 degrees from the planet's axis of rotation, and is also offset from the center of the planet by one-third of the planet's radius.

Auroras on Uranus are not in line with the poles (like they are on Earth, Jupiter, and Saturn) due to the lopsided magnetic field.

The magnetosphere tail behind Uranus opposite the Sun extends into space for millions of miles. Its magnetic field lines are twisted by Uranus’ sideways rotation into a long corkscrew shape.

• NASA Planetary Photojournal: Uranus
• National Space Science Data Center Photo Gallery: Uranus
• Uranus 3D Model
• Uranus Poster - Version A
• Uranus Poster - Version B

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Science News

U.s. planetary scientists want to explore uranus and enceladus next.

In the new decadal survey, researchers also recommend prioritizing a Mars sample-return mission

In the new decadal survey setting priorities for U.S. planetary exploration, researchers recommend sending an orbiter and probe to Uranus. This infrared composite image of the two hemispheres of the ice giant was taken with the Keck Telescope in Hawaii.

Lawrence Sromovsky/Univ. of Wisconsin–Madison, W.M. Keck Observatory

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By Liz Kruesi

April 20, 2022 at 9:14 am

The continuing search for life beyond Earth is driving many of the priorities for what’s next when it comes to U.S. planetary exploration. In a new report that could shape the next 10 years of planetary missions, Mars, Uranus and Saturn’s moon Enceladus have come out on top.

This report is the latest decadal survey for planetary science and astrobiology . Every 10 years, experts convened by the National Academies of Sciences, Engineering and Medicine compile a look at the state of the field and pull together a list of recommended priorities for the next decade of exploration. The new survey, which covers 2023 to 2032, will be used by NASA, the National Science Foundation and others to help guide which projects are pursued and funded.

The survey is meant in part “to identify the key scientific questions that are the most important” to pursue in the next decade and assess how best to answer them, astrophysicist Robin Canup said April 19 during a news conference after the report was released. Canup, of the Southwest Research Institute in Boulder, Colo., is a cochair of the steering committee for the decadal survey.

At the top of the list, the report recommends continuing the Mars sample-return effort by developing a mission that will retrieve, as soon as possible, the rock and soil samples that NASA’s Perseverance rover is collecting and storing ( SN: 9/10/21 ). This multipart sample-return mission was also the top priority of the previous decadal survey , released in 2011 ( SN: 3/7/11 ). Those samples could hold hints of past signs of life on the Red Planet.

The report also suggests that the next Mars mission, after the sample-return one, should look for signs of life in the ice as well as gaseous biosignatures in the atmosphere. That one is farther down the priority list, though.

Next in the line after the Mars sample-return mission is a large, several-billion-dollar mission to send an orbiter and probe to Uranus to explore the planet, its ring system and its moons. Uranus and the solar system’s other ice giant, Neptune, were visited once, in the late 1980s, when Voyager 2 flew by each.

The time has come to go back , scientists say ( SN: 2/10/16 ). “I’m really thrilled to see that they picked a mission to go back and follow up on those incredible discoveries and those wonderful images that Voyager took,” says planetary scientist Linda Spilker of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., who was not involved in the decadal survey. Spilker began her career with Voyager.

What’s more, better understanding the ice giants in our solar system could help scientists decipher the mysteries of faraway worlds. In the hunt for planets outside our solar system, the most common type of known exoplanets are those like Neptune and Uranus.

A mission to Uranus “will be transformative,” says planetary scientist Amy Simon of NASA Goddard Space Flight Center in Greenbelt, Md., and a member of the decadal steering committee. “We’re sure there’s going to be fantastic discoveries.”  

This mission could launch in June 2031 or April 2032, the report suggests. After swinging by Jupiter to use the giant planet’s gravity to fling it faster, the spacecraft would arrive at Uranus 13 years after its launch. Once there, the orbiter would drop a probe in the atmosphere, sampling its composition as never before.

The next highest priority is sending an “orbilander” to Saturn’s moon Enceladus , a world known to have easily accessible liquid water ( SN: 5/2/06 ). NASA’s now-defunct Cassini mission discovered in 2005 that this small moon spews geysers of water into space, and more recent research suggests that water coming from subsurface locales has salts, possibly indicating warm pockets of water interacting with rock — and brewing an environment that may host life ( SN: 8/4/14 ).

This proposed spacecraft would arrive at the moon in the early 2050s, where it would first spend 1.5 years orbiting Enceladus, flying through its watery plumes to sample the liquid. Then the spacecraft would land on the surface for a two-year mission.

“If you want to go and look for life, Enceladus is a very good place to do it,” says planetary scientist Francis Nimmo of the University of California, Santa Cruz, and a member of the decadal steering committee.

Life on other planets isn’t the only thing on planetary scientists’ minds. The report also recommends continuing work on a mission to find and characterize near-Earth objects, like asteroids and comets, in an effort to protect life on the only planet where it’s known to exist.

Two medium-sized missions should be funded in the next decade too, the report recommends. While the survey doesn’t specify targets for these missions, nine higher-priority locales are singled out, including Venus, Saturn’s moon Titan and Neptune’s moon Triton.

The decadal survey also considered the state of the fields of planetary science and astrobiology — namely decreasing funding opportunities and how to improve diversity, equity, inclusion and accessibility efforts. For the latter, the committee looked at whether the community has diverse representation through their members.

“The thing that became abundantly clear is that NASA has done a terrible job of collecting those kinds of statistics,” Nimmo says of demographics in planetary science. For now, the recommendation is to better survey the scientific community, he says.  “We’re not going to be able to solve anything until we actually have better statistics.”

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Why we should send a spacecraft to explore Uranus

What would a mission to explore the 7th planet from the Sun reveal, and how would it get there?

Should we send a spacecraft to explore Uranus? Missions to Mars, Jupiter, Saturn and Pluto have been a resounding success, so why not launch a probe dedicated to studying the 7th planet from the Sun?

The actual mechanics of getting a spacecraft to Uranus is not difficult, although the journey could take some 17 years to complete.

The real problem in sending a probe to Uranus is operating a spacecraft in the icy darkness of the outer Solar System where the planet resides.

But sending a spacecraft to explore Uranus is worth it.

Space probes are usually powered via solar panels but, out at Uranus , a probe would receive just 3% of the sunlight it would get at Earth.

“We would need solar panels between one and two IMAX screens in length,” says Dr Chris Arridge of Lancaster University , who was part of the team that proposed the Uranus Pathfinder (UP) mission to the European Space Agency in the early 2010s.

Its aim was to undertake a complete survey of Uranus, its rings and satellites, but unfortunately UP never got off the ground.

A more realistic possibility than solar panels on a Uranus orbiter would be using a nuclear element that stays warm as it decays. The heat could be used to generate electricity and power the spacecraft.

Once at Uranus, it’s important that a probe is able to transmit data back to scientists on Earth. These problems are challenging, but not impossible to overcome.

• Did you know it's possible to see Uranus with the naked eye? Find out how to see Uranus in the night sky.

What instruments would a Uranus spacecraft need?

Deciding on what instrumentation to include on a spacecraft is rather like going into a massive sweet shop full of expensive chocolates, only to find you have a few pence in your pocket.

Space is at a premium, and only instruments that can be employed across a number of investigations are going to make the final cut.

First of all, a camera is essential. A picture tells a thousand words and a high resolution camera would provide us with stunningly detailed images of the Uranian atmosphere and its rings , while allowing us to map and scrutinise Uranus's moons .

Looking at Uranus in the infrared would reveal details about the composition of the atmosphere at various depths, and allow scientists both to look for aurorae – we already know they exist – and establish how they are generated.

Uranus has the lowest self-luminosity of all the planets in the Solar System, and its cold temperature would imply that it is some three billion years older than it is thought to be.

A magnetometer (a device for studying magnetic fields) is another must-have.

Magnetic fields can give us a window into the interiors of a world, since planets generate magnetic fields in a variety of ways, depending on their composition and size.

Uranus’s field is one the strangest of them all (see Uranus's biggest mysteries below) and working out how it is generated would tell us a lot about its hidden depths.

The magnetometer could also be deployed to help investigate the ice giant’s moons, and another exciting prospect: the search for subsurface oceans under the icy crusts of the two largest satellites, Titania and Oberon.

The idea that moons this far out from the Sun may have liquid oceans is not as far fetched as it seems.

Both moons seem to be composed of equal amounts of rock and ice, and infrared spectroscopic observations have revealed crystalline water on the surfaces of each of them.

If such a discovery is made, it will have implications on how habitable a planetary system can be, and what makes a planet habitable .

Other tools would be useful on a Uranus spacecraft. A microwave instrument would help scientists to fathom the planet’s interior workings and composition, and another to measure Uranus’s temperature and luminosity would also be very helpful.

Ice giants like Uranus are suitably different from the inner rocky planets or the gas giants. They have their own story to tell about how planetary systems form and evolve.

“There is only so much we can do from the ground and a mission like this would really help to answer questions that have puzzled us for decades,” says Arridge.

The Voyager 2 encounter raised new questions beyond the reach of Earth-bound telescopes.

For example, Uranus’s strange magnetic field seems to reconfigure itself every eight hours as the planet rotates. Why this happens is still unknown.

What could we learn from studying Uranus?

Uranus exploration would also allow us to answer more fundamental questions regarding the formation of the Solar System and how it came to be in its current configuration.

Ice giants like Uranus and Neptune are in a class of their own, being suitably different from the inner rocky planets or the gas giants. They have their own story to tell about how planetary systems form and evolve.

Understanding their nature also has wider ranging implications. Many of the exoplanets we’re finding appear to be of similar size to Uranus and Neptune.

If we hope to understand these exoplanets, we need to work out how the ones in our own Solar System work first.

Days and seasons on Uranus are very strange, with each pole experiencing 42 years of darkness followed by 42 years of sunlight.

No doubt the Uranian system will hold many surprises. It may turn out that the planet and its rings are far more dynamic than we ever believed.

Think of the satellite Mab within Uranus’s μ-ring, which is similar to Saturn’s E-Ring.

NASA's Cassini mission at Saturn showed how the moon Enceladus creates the E-Ring: its majestic fountains dump water ice into the system.

Mab is tiny – just 50km across– and so it seems most unlikely that a moon so small could have any internal activity, and yet if it did this would establish exciting new boundaries as to what we thought might be geologically possible.

Uranus's biggest mysteries

Strange axial tilt.

Many planets in the Solar System have an axial tilt. Earth’s is 23.5º and this is what gives rise to our seasons. Uranus, on the other hand, has an axial tilt greater than a right angle, a whopping 98º.

This means the days and seasons on Uranus are very strange, with each pole experiencing 42 years of darkness followed by 42 years of sunlight.

Lack of internal heat

Most planets have an internal heat source. On Earth it is what drives our plate tectonics and volcanism.

The gas giants have greater internal heating and give out much more thermal energy than they receive from the Sun, as does Neptune. Strangely Uranus appears to have very little internal heating.

Strange Magnetic Field

The magnetic field of Uranus is strange in two ways. First, it does not pass straight through the centre like other planetary magnetic fields. As a result, the magnetic field in Uranus’s northern hemisphere is stronger than in it is in the south.

Furthermore, the field is inclined by some 59° from the axis of rotation. Why this is the case is still not certain.

Bashed up Satellites

Many of Uranus’s satellites show a high degree of cratering and impact scars. Indeed, Miranda (pictured above) has a surface that resembles a ‘patchwork quilt’ of different terrains.

The favoured explanation is that Miranda may have been broken up and reformed several times during its history. Quite why there is so much impact scarring on the Uranian moons is still unclear.

This article originally appeared in the October 2014 issue of BBC Sky at Night Magazine.

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From Earth to Uranus: How Long Would it Take to Reach the Ice Giant?

Last Updated: September 29, 2023

When considering the planets, Uranus mostly fades to the background except perhaps for a chuckle at its modern pronunciation or questions regarding how it ended up on its side. When we consider nearby bodies in space, we often wonder and dream about visiting them. 

But, how long would it take to get there? Let’s dive into the various factors to determine how long it would take to travel to Uranus!

The basics of space travel

When calculating travel time you use two basic measurements: the distance and the speed of the vehicle. The average distance between Earth and Uranus is 1.8 billion miles (2.9 billion kilometers), ranging from 1.6 billion miles (2.6 billion kilometers) at their closest to 1.98 billion miles (3.2 billion km) at their farthest. It’s so far away (19.8x further from the Sun than Earth) that it was only discovered in 1781 by William Herschel, making it the first planet to be discovered with a telescope as it cannot be seen with the naked eye (unless you have 20/20 vision and know EXACTLY where to look). However, just as it is here on Earth, travel time highly depends on the route you take.

Related Article: How Far Away Is Uranus From Earth Right Now?

There are typically four factors when considering a more precise flight duration to any astronomical object:

• Whether or not the spacecraft is sent to other celestial objects either for scientific studies and/or a gravity assist using a slingshot flight maneuver. While a quick flyby mainly for a gravity assist will dramatically increase speed and decrease travel time, time spent studying that planetary system becomes a little more complicated in terms of its actual impact on average velocity and travel time.
• The launch vehicle capabilities as much of the speed of the aircraft (disregarding gravity assists and thruster adjustments) will be determined by the speed the rocket can attain after escaping Earth’s gravity, which requires a minimum of 7 miles/ 11.2 kilometers per second (25,000 mph or just over 40,000 km/ hr) just to reach Earth’s escape velocity. As a baseline, the Apollo spacecraft reached a speed of 8 km/sec.
• Slowing down requires time by either reverse-firing thrusters in space or utilizing atmospheric re-entry if landing. A flyby will be shorter than an orbit insertion (which is the best we can do for Uranus since we can’t land on it since there is no surface) or landing on the surface of an object like a moon.
• A planet is not a fixed point in space like a house since it is constantly moving around the Sun. So, we can’t only plan to reach the end destination based on the distance when we launch, but where it will be by the time we reach it. This calculation also has to be done for any gravity assists that will be planned along the trip.

While theoretical flight plans are helpful, what real flight plans can we compare to better understand more realistic travel times to Uranus?

Past missions to Uranus

Only one spacecraft has visited Uranus: Voyager 2. The Voyager spacecraft (1 and 2) were created to perform a “Grand Tour of the Outer Solar System”. Due to budget and other concerns, the missions were whittled down, but still took advantage of a rare planetary alignment to study the outer solar system before heading into interstellar space. Both carried a copy of the Golden Record, a 12-inch/ 30 centimeter diameter gold-plated copper disc that contained a message from humanity to space including examples of life on Earth, greetings, and music as well as instructions on how to play the samples.

Both spacecraft weighed 1,592 pounds (721.9 kilograms) and were launched on top of a Titan IIIE-Centaur rocket. This rocket system was also used to launch the Viking probes and the Helios spacecraft. Voyager 1’s mission focused on studying Jupiter and Saturn before launching toward interstellar space while Voyager 2 completed more of the Grand Tour of the Outer Solar System originally proposed for the project, targeting Jupiter, Saturn, Uranus, and Netprune before launching into interstellar space.

Despite being named Voyager 2, it actually launched earlier on August 20, 1977, versus Voyager 1’s launch date of September 5th, 1977, and is still the only spacecraft to have studied all four of our solar system’s gas giants at close range.

Mission Log of Relevant Key Dates for Voyager 2:

The Voyager spacecraft reached a speed of 17 km/ sec with the aid of gravity assists

So, launch to flyby of Uranus was from Aug. 20, 1977 to Jan. 24, 1986 (eight years, five months) for Voyager 2, but it’s important to remember that it included a gravity assist from Jupiter and a unique line-up of planets that helped to greatly reduce the travel time to each planet.

Related Article: How Much of Space Have We Explored So Far?

Other missions that did not go to Uranus but have tangential Uranus data

NASA briefly considered sending Cassini (the spacecraft that studied Saturn) to Uranus after its primary mission was completed. Travel time from Saturn to Uranus was calculated at a decade. Instead, its primary mission of studying the ringed planet and its moons was extended until its planned plummet into the planet’s atmosphere.

The New Horizons spacecraft’s mission is focused on the dwarf planet Pluto, its moons, and the Kuiper Belt, an icy asteroid belt past Neptune. It is often cited in estimations of space travel because it’s one of the most recent and therefore most advanced propulsion systems, particularly when considering travel to the outer solar system.

The New Horizons spacecraft weighed 1,054 pounds (478 kilograms) and utilized the Atlas V 551 launch vehicle. New Horizons launched on January 19, 2006, and after reaching initial Earth orbit, accelerated the spacecraft to a velocity of about 10.1 miles per second (16.26 km/ s) or 36,400 miles per hour (58,536 kilometers per hour), the highest launch velocity attained by a human-made object relative to Earth. It crossed the orbit of Uranus on March 18th, 2011 while it was in hibernation mode to get to Pluto as quickly and efficiently as possible. Remember that this 5-year trip is not accurate because it did not stop at Uranus which would require extensive maneuvers over the course of months (7 months from approach phase to close approach of Pluto).

Future Missions to Uranus

Missions to Uranus have been proposed over the years, but often tabled in favor of other missions that are deemed of higher scientific value. When planning a mission to the outer solar system, finding an ideal window can take up to a century since Uranus orbits the Sun once every 84 Earth years.

The Uranus Orbiter and Probe is a proposed joint NASA and ESA mission to study Uranus, including deploying a probe into its atmosphere to gather data. Experts estimate the trip to take 12-15 years, primarily depending on the launch date which would determine the distance between the two planets.

The original proposed flight plan listed a launch date of 2031 or 2032 utilizing a Falcon Heavy expendable launch vehicle which would take 13.4 years to reach Uranus (in 2044 or 2045) utilizing a gravity assist from Jupiter, after which it would study the mysterious planet and its moons for a primary mission of 4.5 years (potentially open for an extension or secondary mission depending on the state of the craft). The end of the ideal launch window is 2038, which would necessitate a 15-year journey due to the position of Uranus. NASA has just recently (2023) pushed the launch back due to a decrease in plutonium production, meaning a mid-to-late 2030s launch is more likely.

If we could reach Uranus by 2049, we have the chance to have the most contrast with Voyager 2’s data during the planet’s southern hemisphere’s summer, if it can arrive before southern spring begins in 2049.

Other Considerations

Parker solar probe.

The Parker Solar Probe currently holds the record for the fastest spacecraft at 364,745 mph 587,000 km/hr in 2021. Theoretically, at its 2021 speed, Parker could reach Uranus in about 206 days, but part of the reason Parker’s speed is so high is that it is falling into the Sun’s gravity versus trying to escape it so this speed wouldn’t actually be achievable on a trip to Uranus.

Crewed spacecraft

None of these missions has human occupants. We need to go slower to accommodate our fragile bodies. In fact, the fastest that humans have ever traveled in space is 24,791 mph (39,897 km/ hr), which was achieved by the returning Apollo 10 astronauts in May 1969.

It takes an average of 6 hours to three days for astronauts to travel on a Soyuz rocket to the International Space Station which sits at an altitude of about 253 miles (408 km). However, SpaceX launches to the ISS currently average 24 hours with the SpaceX Crew-4 mission in May of 2022, clocking in at less than 16 hours. 

The new NASA SLS system designed to bring humans back to the moon has a top speed of over 6 miles/9.7 km per second which roughly equates to over 21,600 mph or 34,920 km/hr, but that may change as the missions continue to develop and as technology continues to improve in both engines and protecting the human body.

A spacecraft with humans onboard would likely take 14-17 years to reach Uranus in the near future (considering the distances between the two planets). It is important to remember that the ongoing and upcoming missions to return humans to the moon also prepares us to go to Mars by the 2040s. These future missions will help us adapt and innovate to further innovate human exploration of the solar system.

Theoretical Light Speed

Uranus sits at about 1.8 billion miles (2.9 billion kilometers) away The calculation is highly dependent on the speed achieved, the route, the number of “stops”, the number of gravity assists, and the approach procedure in which we slow down. Do we go straight to Jupiter or utilize gravity-assist maneuvers from other planets, especially to save on fuel?

Based on previous and planned upcoming spacecraft missions to Uranus, it would likely take 12-15 years for a probe to travel that distance, at least factoring in a launch in the next decade or so. For humans, it would likely take closer to 14-17 years to safely travel there due to what our bodies can withstand, but that number will likely decrease due to innovations by the time we are actually considering sending a human to the pale blue seventh planet or one of its moons.

If one thing is clear from calculating the time it would take to get to Uranus, it is that human ingenuity allows us to accomplish amazing feats and surpass even what were once our greatest achievements. Even within the next decade or two, this timetable could be very different depending on the current state of technology, and that is the beauty of scientific progress.

Written by Sarah Hoffschwelle

Sarah Hoffschwelle is a freelance writer who covers a combination of topics including astronomy, general science and STEM, self-development, art, and societal commentary. In the past, Sarah worked in educational nonprofits providing free-choice learning experiences for audiences ages 2-99. As a lifelong space nerd, she loves sharing the universe with others through her words. She currently writes on Medium at  https://medium.com/@sarah-marie  and authors self-help and children’s books.

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More From Forbes

Hit and run tourism: what does it mean to ‘visit’ a country.

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Mount Everest, Nepal which is suffering from overtourism—400 people have been to every ... [+] country/territory in the world

Hit and run tourism is everywhere on the news, with people bemoaning the bad behaviour of tourists converging on one picture or sculpture before rushing onto the next, or taking selfies in inappropriate locations and then moving on, leaving behind mounds of litter and noise. What's clear is that there are ways that tourists can be motivated to change their behavior and some traveler groups are trying to create consensus around what it actually means to visit a country.

More People Are Visiting Every Country In The World

There's a small group of people who have visited every country in the world—about 400 or so, as reported by CNN . In 2023, though, 50 people joined this group, more than ever before, and they can all say they have been to all 195 UN-recognized countries and territories.

There are more organizations welcoming these travelers too. The Travelers Century Club was the first to launch in 1954—its members need to have visited 100 or more countries and territories. Now there are also two others, Nomad Mania and Most Traveled People.

Most people in these clubs don't suddenly decide to travel to every country in the world. Many, such as Rauli Virtanen who is believed to be the first person to have traveled to every country in the world, are already incredibly well traveled before they decide to make it a mission.

Many, as Virtanen acknowledges, can only travel the world because they are fortunate to have the right passports coupled with enough wealth (or jobs that pay for travel expenses).

Travel, however, has always been a competitive sport—whether that be Ernest Shackleton getting to the Antarctic, Edmund Hillary and Tenzing Norgay climbing Mount Everest or Amelia Earhart crossing the Atlantic. Today's equivalent is probably to visit every country. Ugandan-American travel influencer Jessica Nabongo became the first Black woman to document her travels to every country in 2019 and Gunnar Garfors is the first person to visit every country in the world twice.

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Apple s iphone 16 pro design revealed in new leak, charlotte shooting 4 officers killed while serving warrant, more and more people are complaining of 'hit and run' tourism.

Now that visitor numbers are springing back to pre-pandemic levels, some of the old travel nuisances have also returned. Gion district in Kyoto, Japan, is reporting that tourists are causing a nuisance when trying to take photographs of the women Geishas and that while on-the-spot fines exist, they are unenforceable.

Milan's mayor wants to ban gelato and alcohol sales after midnight to preserve the city's tranquility and Japanese authorities are to build a big wall blocking the view of Mount Fuji from a gas station because of badly-behaved tourists stopping for a selfie and leaving litter everywhere.

The same kind of tourism is happening because of Netflix's Emily in Paris. The show portrays a side of Paris that critics say is stereotypical, and simply untrue (could 'Emily' afford the apartment she has on her salary?) but more insidiously for critics, it has encouraged a form of Parisian tourism that is only interested in a form of collection, identical to the character. The photo eating the same pain au chocolat in the same boulangerie. Tick. The photo drinking the same chocolat chaud in the same 18th century tearoom. Check. For some travelers, the only way to live an experience is by taking a picture and then posting it.

So, What Does It Really Mean To Travel To A Country?

So maybe the real question is, what does it mean to 'visit' a country? Is it spending time there, even if we never speak a word of the language? Never speak to a local? Nomad Mania members suggest that 'a visit' should normally constitute things such as passing through immigration, staying a night, and traveling in a moving vehicle.

The Director of the Galleria dell’Accademia in Florence, best known for housing Michelangelo’s David, notes that there are also different ways that people can be encouraged to pass through some of the world's most famous—and most Instagrammable—locations. Writing in The Guardian , Cecilie Hollberg suggests several things that have worked to reduce such 'hit and run' tourism in her museum—holding exhibitions in winter, extending opening hours, getting the local residents involved, changing signage and museum trajectories so that visitors don't all head straight for selfies with David, as well as reducing the numbers in tour groups.

In the age of the climate crisis, it might also depend on how we travel. Torbjørn “Thor” Pedersen set off from Denmark in 2013 to visit every country without flying and he finally arrived in his final country, the Maldives, in May 2023 after 9 years and 203 countries/territories and returned to Denmark by ship. Some travel challenges it seems can be slow burn and meet current Instagram trends.

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By Catie Edmondson ,  Martín González Gómez ,  Kayla Guo ,  Robert Jimison ,  Albert Sun and Karen Yourish

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Source: Office of the Clerk, U.S. House of Representatives

The House passed a long-stalled foreign aid package on Saturday that gives funding to Ukraine, Israel and Taiwan, with a majority of lawmakers backing money for American allies across the globe. The package, which now goes to the Senate, is almost certain to become law.

The Senate passed similar legislation in February. But in the face of distinct bases of opposition to different elements of the legislation, which threatened to tank the package as a whole, Speaker Mike Johnson advanced the foreign aid using a convoluted strategy: It split the package into three parts, each of which received its own vote, added a fourth bill with Republican priorities as a sweetener and melded it all together again once everything passed.

The plan, laid out in a rule that passed on Friday, was concocted to capitalize on the pools of support for each part of the $95 billion package, while preventing opposition to any one piece from taking down all of them.

How Different Factions Voted

Note: Progressive Democrats are members of the House Progressive Caucus. Hard-right Republicans include members who were supported by the House Freedom Fund during the 2022 midterms, opposed Kevin McCarthy’s election as speaker in January 2023, or voted to oust Mr. McCarthy from the speakership last October. The fund is the campaign arm of the House Freedom Caucus, a hard-right faction founded in 2015.

A majority of Republicans voted against Ukraine aid on Saturday, in a reflection of the stiff resistance within the G.O.P. to continuing to aid Ukraine against President Vladimir V. Putin of Russia’s invasion. The coalition that voted against the bill extended from right-wing members of the House Freedom Caucus to leadership, such as Representative Elise Stefanik of New York, the No. 3 House Republican. On Israel aid, on the other hand, most Republicans voted “yes.”

Thirty-four right-wing Republicans also opposed aid to American allies in the Indo-Pacific, while Representative Rashida Tlaib, Democrat of Michigan, declined to take a yes-or-no position and voted “present.” Representative Bob Good, Republican of Virginia and the chair of the House Freedom Caucus, was one of the 21 members of his party who voted against the Israel package. Echoing one of the many grievances shared by hard-right Republicans who opposed all of the aid measures, Mr. Good said his support for “Israel’s right to defend itself remains unshakeable” but that he disagreed with a measure that would add to the nation’s debt.

While all Democrats voted in favor of aid to Ukraine and all but Ms. Tlaib supported funding to Taiwan, 37 left-leaning Democrats defected to vote against the Israel aid bill. They said before the vote that they opposed unfettered aid to Israel that could be used in its offensive in Gaza. The opposition to the Israel aid represented a minority of Democrats, but reflected the deep resistance to unconditional aid and the divisions in the party on Gaza. Representative Jamie Raskin of Maryland represented a notable new “no” vote among Democrats, and other standouts included Representatives Donald S. Beyer Jr. of Virginia, Earl Blumenauer of Oregon and John Garamendi of California.

Still, 37 “no” votes, while a break from Washington’s ironclad support for the Jewish state, fell short of the opposition bloc progressives had hoped to muster. Thirty-nine Democrats had voted “no” on Friday on the rule to allow the foreign aid package to come to the House floor, a target that progressives just missed on Saturday on the Israel bill. Fourteen of those Democrats voted on Saturday in favor of aid to Israel, while 12 Democrats who voted to allow the package on the floor on Friday then cast votes against the funding itself.

Twenty-five Republicans voted against the fourth bill, which included measures that could lead to a ban on TikTok in the United States and that would redirect funds from seized Russian assets to help aid Ukraine. Democrats put up a big vote — 174 — in favor of this bill, which was intended to sweeten the overall package for conservatives.

How Every Member Voted

An earlier version of this article incorrectly identified the political party of a group of representatives who notably voted “no” on new aid for Israel. They are Democrats, not Republicans.

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