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  • The recent reigning Queen of everything, once saidIf you like it, then you shoulda put

  • a ring on it”, well I like the Earth, why wasn’t a ring put on it?

  • Hey everyone, Julia here for Dnews.

  • A researcher from the University of Rochester, Eric Mamajek, recently took another look at

  • some odd readings from a star 420 million light years from Earth. The starlight emanating

  • from the faraway solar system seemed to dim frequently indicating a planet passing in

  • front of it. In most cases like this, the dimming lasts a few hours, however this star’s

  • dimming was lasting a few months.

  • His interpretation? A scaled up version of Saturn. A big planet with HUGE RINGS. This

  • planet would be about 10-40 times the size of Jupiter. Its rings? EVEN BIGGER. If they

  • exist, they would span the width of here to the sun. That’s 93 million miles. It’s

  • so big, it leaves many scientists skeptical.

  • So while they still puzzle over that mystery, let’s take a look at why planetary rings

  • form at all.

  • Four of the planets in our solar system have rings, the gas giants, Jupiter and Saturn,

  • and the ice giants Uranus and Neptune. Their rings aren’t a giant solid disk, theyre

  • a bunch of smaller rings made up of smaller particles, like bits of rock and dust and

  • even ice.

  • Saturn’s big ring is made up of thousands of smaller wide rings of ice that reflect

  • a lot of sunlight, so theyre super visible to us on Earth, I mean with a telescope of

  • course. Galileo first discovered Saturn’s rings in 1610. Jupiter, Uranus, and Neptune’s

  • rings are thin and dusty, so theyre not as visible to us and took a little longer

  • to find. Jupiter’s rings weren’t discovered until 1979 by the Voyager 1 space probe and

  • Neptune’s weren’t found until a decade later, by the Voyager 2 space probe.

  • Planetary rings form in a few ways: Possibly in the early days when the planets were forming

  • from a mass of space dust, this debris never made it into the final planet, so it just

  • kind of hangs out in orbit. Or the rings might form when planetary satellites, like a moon,

  • get too close and get pulled apart by the planet’s gravity. These two theories could

  • explain Saturn’s rings. Most of the other planet’s dusty, thin rings formed when their

  • moons were hit by something and that impact kicked up dust and particles.

  • The earth had a ring too once. It just coalesced into the moon. So why don’t Saturn’s rings

  • turn into a moon? The rings are simply too close to the planet. They are within what

  • is called The Roche Limit named after a French astronomer, Edouard Roche, who calculated

  • this theoretical limit in 1848. Inside the limit, the debris remains as rings. Outside

  • of the limit, debris coalesces into larger bodies, like a moon. When a satellite, like

  • a moon, gets too close to the planet and it can’t withstand the tidal forces caused

  • by the planet’s gravity, it disintegrates. Our moon is out side of the Earth’s Roche

  • limit, so it remains spherical. But what if it fell into the Roche Limit? What if the

  • Earth had rings like Saturn? It would look pretty awesome, something like this.

  • What do you think? how cool would it be if earth had rings? let us know in the comments

  • below!

The recent reigning Queen of everything, once saidIf you like it, then you shoulda put

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為什麼地球沒有環? (Why Doesn’t Earth Have Rings?)

  • 162 16
    Wayne Lin 發佈於 2021 年 01 月 14 日
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