February 16, 2011

Tyche, the new ninth planet

John Matese and Daniel Whitmire, astrophysicists from the University of Louisiana at Lafayette, think data gathered from NASA’s Wise telescope will reveal a ninth planet orbiting in the Oort cloud, captured from another solar system by the sun’s gravity.

Whether it would become the new ninth planet would be decided by the International Astronomical Union (IAU). The main argument against is that Tyche probably formed around another star and was later captured by the Sun’s gravitational field. The IAU may choose to create a whole new category for Tyche, Professor Matese said.

Tyche will almost certainly be made up mostly of hydrogen and helium and will probably have an atmosphere much like Jupiter’s, with colourful spots and bands and clouds, Professor Whitmire said. “You’d also expect it to have moons. All the outer planets have them,” he added.


  1. Casey on February 16th, 2011 at 10:34 am

    “All the outer planets have them.”
    Don’t fall prey to the pressure to have moons too soon, Tyche. You’re different.

  2. Tycho on February 16th, 2011 at 11:22 am

    I wonder why they strayed from the usual nomenclature of planets. Tyche seems to be paying tribute to Tycho Brahe, instead of the mythological gods like Mars, Pluto, Venus, etc.

  3. Deron Bauman on February 16th, 2011 at 11:24 am

    To the Greeks, Tyche was the goddess responsible for the destiny of cities. Her name was provisionally chosen in reference to an earlier hypothesis, now largely abandoned, that the Sun might be part of a binary star system with a dim companion, tentatively called Nemesis, that was thought responsible for mass extinctions on Earth. In myth, Tyche was the good sister of Nemesis.

  4. Cindy Scroggins on February 16th, 2011 at 5:59 pm

    My maiden name is Hyche. I’m pretty sure they were aiming to name it after me and made a typo.

  5. Kyle Anderson on February 16th, 2011 at 6:01 pm

    I agree with others… that Tyche is most likely the large dark object predicted for many years as the culprit (Nemesis) perturbing cometary nuclei in and around the Oort cloud and sending them Earthward. Its mass, if confirmed, may indicate that it is more stellar than planetary, like a brown dwarf or proto-star.

  6. Tycho on February 16th, 2011 at 8:04 pm

    Well there we have it. Next time I will do better to do some digging!

    Thanks, Deron.

  7. Daryl Scroggins on February 16th, 2011 at 8:40 pm

    What I like to imagine is that the first visitor to our system–from another planetary system–will be a planet with a rich, but dead, archeology. What a lesson that could be: the story without the immediate threat; the call to humility, and perhaps greatness as well.