Credit: NASA
Looks like game over for the Planet Nine idea. Unavoidable observational biases may be at least partly to blame.
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Planet Nine is a theoretical, undiscovered giant planet in the mysterious far reaches of our solar system, says The Conversation (via Phys.org)
The presence of Planet Nine has been hypothesized to explain everything from the tilt of the sun’s spin axis to the apparent clustering in the orbits of small, icy asteroids beyond Neptune.
But does Planet Nine actually exist?
Discoveries at the edge of our solar system
The Kuiper Belt is a collection of small, icy bodies that orbit the sun beyond Neptune, at distances larger than 30 AU (one astronomical unit or AU is the distance between the Earth and the sun).
These Kuiper Belt objects (KBOs) range in size from large boulders to 2,000 km across. KBOs are leftover small bits of planetary material that were never incorporated into planets, similar to the asteroid belt.
The discoveries from the most successful Kuiper Belt survey to date, the Outer Solar System Origins Survey (OSSOS), suggest a sneakier explanation for the orbits we see.
Many of these KBOs have been discovered to have very elliptical and tilted orbits, like Pluto.
Mathematical calculations and detailed computer simulations have shown that the orbits we see in the Kuiper Belt can only have been created if Neptune originally formed a few AU closer to the sun, and migrated outward to its present orbit.
Neptune’s migration explains the pervasiveness of highly elliptical orbits in the Kuiper Belt, and can explain all the KBO orbits we’ve observed, except for a handful of KBOs on extreme orbits that always stay at least 10 AU beyond Neptune.
Continued here.
via Tallbloke’s Talkshop
May 26, 2020 at 07:54AM
Iowa Climate Science Education 