Why do some planets have rings?

Saturn

We know many planets that have some kind of ring system. And the most well-known of those planets is Saturn. All gas giants in our solar system have a ring system that orbits them. So there are many theories about the origin of those rings. 

There is the possibility that forming of the rings is unique. So that means there are more than one reasons why some planets have rings. But if we are thinking about the gas giants in our solar system we must realize that those planets are more distant than Earth. 

So solar wind in that area is weaker than in the Earth's distance. And that means the particle (or ion) flow from the Sun would not blow those particles away. That explains why Earth has no rings. The reason for that is the solar winds. That are blowing sand or some other particles away from the Earth's orbiter. 

"The backlit (of Saturn's) E ring, with Enceladus, silhouetted against it. The moon's south polar jets erupt brightly below it." (Wikipedia/Rings of Saturn)

There may be many things that are forming ring systems for planets. There are three of those theories. And maybe there are many other reasons why some planets have rings. And some have not. 

*Plasma- or Van Allen rings of the planets are capturing sand bites that travel at the solar system. 

*In the case of Saturn, the shepherd moons are also playing their role in forming and anchoring the ring system. The shepherd moons are moons. That is orbiting the ring system on both sides of it. And the gravitational fields anchoring the objects in their places. 

*The Van Allen belts could capture small particles. And that explains why Uranus' rings seem to have no shepherd moons. The Van Allen ring or plasma ring can capture very light and slow-speed objects. So that means there could be many reasons why some planets have rings. 

*If the planet's distance is high enough from the Sun solar wind would not blow that dust away. 

*Destruction of the ancient moon can explain ring systems that involve large particles. 

*That moon could be destroyed by cosmic impact. Or tidal forces of the planet and its other moons can destroy that ancient moon. 

The planets with ring systems 

a) Jupiter's rings

a) "A schema of Jupiter's ring system showing the four main components. For simplicity, Metis and Adrastea are depicted as sharing their orbit. (In reality, Metis is very slightly closer to Jupiter.)" (Wikipedia, Rings of Jupiter) 

a2)

"Metis orbiting at the edge of Jupiter's main ring, as imaged by the New Horizons spacecraft in 2007" (Wikipedia/Rings of Jupiter)

b) Saturn's rings

"Side view of Saturn system, showing Enceladus in relation to the E Ring" (Wikipedia/Rings of Saturn)

b2)

"The full set of rings, imaged as Saturn eclipsed the Sun from the vantage of the Cassini orbiter, 1.2 million km distant, on 19 July 2013 (brightness is exaggerated). Earth appears as a dot at 4 o'clock, between the G and E rings." (Wikipedia/Rings of Saturn)

c) Uranus rings

"The scheme of Uranus's ring-moon system. Solid lines denote rings; dashed lines denote orbits of moons". (Wikipedia/Rings of Uranus)

"The scheme of Neptune's ring-moon system. Solid lines denote rings; dashed lines denote orbits of moons".

d) Neptune rings

d2) "Rings of Neptune imaged by the James Webb Space Telescope's NIRCam instrument" (Wikipedia/Rings of Neptune)

*There is the possibility that the planet capture the large dwarf planet and then the tidal forces will rip that dwarf planet in pieces. 

*In that case. The shepherd moons or moons that are orbiting the planet at both sides of the ring system are anchoring those objects in their places with their gravitational effects. 

And that means there is a possibility the plasma rings or Van Allen rings of giant planets capture dust, asteroids, and comets that travel in solar systems. And at least in cases where the ring system is formed of sand or other way saying small-size particles. That is the reason why some gas planets have rings. 

Another reason could be the ancient moon that is broken by cosmic impacts. That thing can be a reason, for planets like Saturn have larger objects in their rings. When that hypothetical moon is destroyed. The particles that are remaining of that ancient moon left to orbit Saturn. 

In some of this theory's other versions, Saturn collided with an asteroid cloud that could be the remnant of some ancient dwarf planet and some of those remnants remained to orbit that planet as the well-known ring system. 

https://scitechdaily.com/why-are-some-planets-surrounded-by-rings/amp/

https://en.wikipedia.org/wiki/Rings_of_Jupiter

https://en.wikipedia.org/wiki/Rings_of_Neptune

https://en.wikipedia.org/wiki/Rings_of_Saturn

https://en.wikipedia.org/wiki/Rings_of_Uranus

https://en.wikipedia.org/wiki/Tidal_force

By the way...

The idea of the solar ring- or ring-shaped solar panels is taken from the planetary rings and one hoax theory. 

There is one UFO theory that I want to mention here. That theory is that the Uranus ring system is the solar panels that are orbiting the gas planet. Today that theory is crushed, but it gave an idea that maybe in the future Earth and some other planets or space colonies will get their power from solar panels that orbit the planets. 

The energy will transport to those colonies in the form of radio- laser or microwaves. That kind of solar ring or extremely thin silicone panels might solve the energy problems of the future. If those solar rings or ring-shaped solar panels are rotating or orbiting the Earth or some other planet the gravitational and centripetal force would have the same power, and they would anchor that solar panel in place. But that thing requires that the panels will move all the time. 

It's possible that between the center planet and the inner edge of the silicone panels is the frame. The orbiting silicone panel delivers energy to that stable frame. And that frame sends energy to the receiving stations on Earth. 

Image: Pinterest

https://astronomyandtechnology.blogspot.com/

How to get to Jupiter orbiter in 1 year?

From Pinterest

The Pioneer 10 flew to Jupiter in about a year. The Galileo probe used almost 2000 days for that journey. And the reason for that was simple. The Galileo probe was the orbital mission. And it should slow down its speed for reaching the orbiter. 

The total flight time of the Galileo probe was more than six years. The reason for that is simple. Galileo's flight time to Jupiter was announced from the last gravitational assists. 

While it made its mission, the Galileo probe made two gravitational assist flybys with Earth and one with Venus. As I wrote before. But is it possible to send the orbital probe to Jupiter or other planets in less than two years? There are two theoretical ways to make that thing. 

1) Main craft makes the flyby and sends the parasite probes to orbital trajectory. 

Sometimes is introduced an idea of an interplanetary or even interstellar mission is a combination of the flyby and orbital missions. The system includes two types of probes. The main probe would fly through the solar system at a very high speed. And its parasite- or sub-probes will send to orbital trajectories. 

The idea is introduced in the "Daedalus" plan. The plan was to create a massive, unmanned probe that makes flyby of the planets or other stars. And during that flyby, it sends its smaller sub-probes that use ion or nuclear engines to slow down. In that version, the smaller probe uses nuclear thermal propulsion or some other power system, to decrease its speed to a level where it can reach the orbital trajectory.

"Daedalus" (Wikipedia, Project Daedalus)

2) The other craft will dock to the main mission unit during the gravitational assist maneuver. 

This idea is a little bit more conventional than "Daedalus". The idea is to use a similar mission profile to the "Galileo probe". The larger craft will put to make gravitational assist flybys to Earth and Venus. Then the smaller probe will drive at the front of the craft. And then the larger device that is loaded with gravitational energy will drive to catch up with the smaller probe. 

The larger probe can fly between the Earth and Venus for many years. And then the other probe will dock to it. The reason, why the Galileo probe didn't use the sun as a gravitational sling. Is that the connection between the probe and mission control is cut. When it's on another side of the sun. But the modern artificial intelligence makes it possible that the probe can find Earth independently and re-establish a connection. 

If we would use that gravitational sling with manned space missions. There is a problem that the crew must wait on Earth for a very long time before their docking capsule will launch. 

When we are talking about the long-term space missions the crews are extremely well selected. Their social relations are the key element for mission success. And if one of those members will injure by accident that would be a catastrophe. 

https://www.universetoday.com/128259/long-take-get-jupiter/

https://en.wikipedia.org/wiki/Project_Daedalus

https://writingsaboutmysteries.blogspot.com/