A team of NASA scientists is asking for a change. They have proposed a planets redefinition, one that could change the view of our Solar System. If their definition is approved, Pluto could once again be considered a planet. And so would our Moon and over 100 other space bodies.
Scientists have long since been debating on what actually makes a space body a planet. And such discussions seem to have only intensified since Pluto’s demotion back in 2006. Once considered the ninth planet in our Solar System, its status was questioned.
Back in 2005, the IAU took a formal step on the matter. It released an official definition for the term ‘planet’. The IAU is the International Astronomical Union.
But now, a team of scientists is asking for a planets redefinition. One that could change the meaning behind the term. And which would bring significant changes if applied.
The definition change proposal will be presented during the Lunar and Planetary Science Conference. This will be taking place in between March 20 to 24. It will be held at the Woodlands Waterway Marriott Hotel and Convention Center in the Woodlands, Texas.
This planets redefinitions proposal was titled as follows. “A Geophysical Planet Definition”. And the team that advanced it is being led by Alan Stern. He is the principal investigator of the NASA Pluto mission, New Horizons.
Presently, a planet has to meet the following requirements. 1. It has to be a celestial body orbiting around the Sun. 2. It has to have sufficient mass as to develop a self-gravity. This will help it gain a hydrostatic equilibrium or nearly round shape. 3. It also has to have cleared the area around its orbit.
The key and biggest definition change is targeting point 1. As such, researchers are hoping to remove the respective rule. This would mean that cosmic bodies won’t necessarily need to orbit the Sun. Not in order to be considered a planet.
Instead, Stern and his colleagues are proposing the following. They are asking for an intrinsic physical properties evaluation. This would analyze the cosmic body itself. And not its interaction with other stars.
Pluto was demoted due to this latter. The dwarf planet has yet to clear its orbit’s neighborhood.
According to the researchers, their proposed planets redefinition will be soon submitted to the IAU. And it will be focused on emphasizing the intrinsic properties. Their geophysical definition is based on the space body’s direct physics. And not on the physics of its interaction with other objects, as it is now.
Besides offering a new definition, the researchers also demote the current one. They considered it to be “inherently flawed”. And for several reasons. As such, they consider their definition to hold more “merit” in terms of the analyzed properties.
A planets redefinition would reinstate Pluto to its former status. But it may also elevate other space bodies to it as well. Even our satellite, the Moon, would fit the new classification. As well as other Solar System moons. For example, Europa, Enceladus, Ganymede, and Titan.
The IAU will have to take quite a significant decision. One that will be heavily analyzed. If the authority does decide to change the planet definition, it will most likely take quite some time. The reason behind the change, be it this proposal or another, would not matter.
The matter would still stand as the IAU would have some serious deliberating to do. Only then would such a decision become official. Complete details about the planets redefinition can be read in the proposal. It also remains to be seen if the IAU will seriously take into consideration the need for a definition change.
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