Space, New Hypotheses About “Planet 9”

Is there a “Planet 9” in our solar system? This is something that astronomers have been studying for some time, in the search for what is also known as the “Ghost Planet” or “Planet X.” Updated information on this hypothetical celestial body, still “elusive” to our cosmic observations, was received from a study conducted by Harsh Mathur of Case Western Reserve University and Katherine Brown of Hamilton College and published in the Astronomical Journal under the title “Modified Newtonian Dynamics as an Alternative to the Planet Nine Hypothesis.”

“A new class of Kuiper belt objects (KBOs) that lie beyond Neptune (…) show orbital anomalies that have been interpreted as evidence for an undiscovered ninth planet,” says the abstract of the paper. “We show that a modified gravity theory known as MOND (Modified Newtonian Dynamics) provides an alternative explanation for the anomalies using the well-established secular approximation.”

The theoretical physicists who wrote the study analyzed the influence that our galaxy, the Milky Way, can have on the outermost region of the solar system in accordance with the laws of “Modified Newtonian Dynamics.” The theory is based on the hypothesis that Newton’s law of universal gravitation is not always true. In other words, it has limits where the gravitational acceleration becomes small enough, then MOND predicts that a different gravitational behavior will prevail.

Thus, the MOND theory was applied to the study of the outermost solar system to explain anomalies that previous studies had found to be compatible with the existence of a planet nine.

“Historically,” conclude the authors, who in any case admit that they were working with a limited amount of data, “claimed gravitational anomalies in the solar system have almost invariably proven to be spurious under closer examination (…), but they have also led to the discovery of Neptune and helped establish general relativity. It is possible that the Kuiper Belt anomalies are evidence of Planet Nine, or that they are spurious (…); alternatively, they may be evidence for a modification of Newtonian gravity.”