Good evidence for 9th planet in solar system
Good evidence for 9th planet in solar system This artistic rendering provided by California Institute of Technology shows the distant view from Planet Nine back towards the sun. (R. Hurt/Infrared Processing and Analysis Center/Courtesy of California Institute of Technology via AP/Thinkstock)
Good evidence for 9th planet in solar system
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Scientists have reported they finally have "good evidence" for Planet X, a true ninth planet on the fringes of our solar system.
The gas giant is thought to be almost as big as Neptune and orbiting billions of miles beyond Neptune's path - distant enough to take 10,000 to 20,000 years to circle the sun.
This Planet 9, as the two California Institute of Technology researchers call it, hasn't been spotted yet. They base their findings on mathematical and computer modeling, and anticipate its discovery via telescope within five years or less.
The two reported on their research Jan. 20 in the Astronomical Journal because they want people to help them look for it.
"We could have stayed quiet and quietly spent the next five years searching the skies ourselves and hoping to find it. But I would rather somebody find it sooner, than me find it later," astronomer Mike Brown told The Associated Press.
"I want to see it. I want to see what it looks like. I want to understand where it is, and I think this will help."
Once it's detected, Brown insists there will be no Pluto-style planetary debate. Brown ought to know. He's the so-called Pluto killer who helped lead the charge against Pluto's planetary status in 2006. (It's now officially considered a dwarf planet.)
His colleague in this latest Planet 9 report, also from Caltech in Pasadena, is planetary scientist Konstantin Batygin.
"For the first time in more than 150 years, there's good evidence that the planetary census of the solar system is incomplete," Batygin said, referring to Neptune's discovery as Planet 8.
The two shaped their prediction on the fact that six objects in the icy Kuiper Belt, or Twilight Zone on the far reaches of the solar system, appear to be influenced by only one thing: a real planet.
Brown actually discovered one of these six objects more than a decade ago, Sedna, a large minor planet way out there on the solar system frontier.
"This is a prediction. What we have found is a gravitational signature of Planet 9 lurking in the outskirts of the solar system," Batygin said. "We have not found the object itself," he stressed, adding that the actual discovery when it happens will be "era-defining."
Added Brown: "We have felt a great disturbance in the force."
Depending on where this Planet 9 is in its egg-shaped orbit, a space telescope may be needed to confirm its presence, the researchers said. Or good backyard telescopes may spot it, they noted, if the planet is relatively closer to us in its swing around the sun. It's an estimated 20 billion to 100 billion miles from us.
The Caltech researchers prefer calling it Planet 9, versus the historical term Planet X. The latter smacks of "aliens and the imminent destruction of the Earth," according to Brown.
The orb - believed to be 10 times more massive than Earth and 5,000 times more massive than dwarf Pluto - may well have rings and moons.
The last real planet to be discovered in our solar system was Neptune in 1846. Pluto, discovered in 1930, was once the 9th planet but is now considered a dwarf planet in the Kuiper Belt. It was visited by Earth for the first time last July. NASA's New Horizons spacecraft accomplished the first-ever flyby.

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Why wasn't this planet discovered before?
Write your answers in the comments section below

  • erino-6-bar
    1/28/2016 - 11:14 p.m.

    This planet was not discovered before because the planet has never been spotted. In fact, the scientists who discovered it had based their findings off of only "mathematical and computer modeling," which shows that, despite there being much evidence that suggests the planet does exist, there is still a chance it does not exist. Since there is no absolute proof, it seems logical that it would take a very long time to discover this so called 'planet-x.'

    I was fascinated by this article because the thought that in only a few years, kids could be learning about this new planet is simply astounding.

  • holdeno-3-bar
    1/28/2016 - 11:30 p.m.

    This planet was not discovered before because it is very hard to spot by telescope. When guessing where Planet 9 may lie, scientists said "it's an estimated 20-100 billion miles away from us" (par. 14) In comparison, Pluto and Earth are only 4.67 billion miles away from each other at most! This planet is so far away from the confines of our solar system that telescopes need a very precise line of sight to spot it, which is why it hasn't been found before now.
    I am skeptical about the existence of Planet Nine because no visual evidence exists to support it.

  • sagew-mea
    1/29/2016 - 11:56 a.m.

    It is so far out that very little light makes it that far. It also Is on an elliptical orbit so it is rarely in sync with earth.

  • jacobm1-mea
    1/29/2016 - 11:59 a.m.

    The reason we have not found it before it because he has technology we didn't have 10 years ago. Plus it very far away.

  • lanes-mea
    1/29/2016 - 01:27 p.m.

    This planet was not discovered before because we did not have enough technology to see that far and it was just recently noticed that the kuiper belt is being effected by its gravitational pull.

  • wesleya.-cam
    1/29/2016 - 02:47 p.m.

    The planet wasn't discovered because of the distance of the planet was very distant. If it takes 10,000 to 20,000 years to circle our sun one time, it is VERY far away. This planet is also a gas giant, making it harder to detect. It also hides behind some other planets in our system and it is behind them. We cannot see it which makes us think there is not a planet there. The article also mentions how the planet supposedly has an egg shaped rotation instead of a circular. That may make it harder to detect.

  • summerf.-cam
    1/29/2016 - 02:53 p.m.

    This planet wasnt dicovered before, because it hasnt even been spotted before. The only way they ¨think¨ theres a ninth planet is cause of computer and mathematically modeling. The scientist wanted to tell everyone so people could help them find the planet. What if theres really no ninth planet after all? All this hard work and research down the drain but, what if there really is an ninth planet, I guess well have to find out.

  • laviniap.-cam
    1/29/2016 - 02:56 p.m.

    We are far more evolved in our world. Technology has influenced this change, even discovering the ninth planet. Discovering Planet 9 in the early 1900's wouldn't have been as accurate as it is now. Without the help of telescopes, mathematicians, or even something as simple as an area to look at the sky, Planet 9 wouldn't have even been found.

  • noellem-jon
    2/01/2016 - 09:49 a.m.

    This planet wasn't discovered before because there is no sold proof of it. Scientists are saying there is a planet 9 based off of "mathematical and computer modeling". So there is a chance this planet does not exist.

  • jelahw.-cam
    2/01/2016 - 07:25 p.m.


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