Scientists have figured out that Pluto’s size is approximately 2,370 km (or 1,473 miles) in diameter, which is much larger than previously thought. Such a conclusion was made on the basis of images obtained with the "Long Range". The results of the study confirm what scientists supposed: Pluto is more than any other known object in the solar system beyond the orbit of the planet Neptune.
“There have been many debates on the size of Neptune since 1930. We can finally put this matter aside,” said Bill McKinnon, a scientist at Washington University in Sain-Louis.
Due to the size of the planet, it can be concluded that its density is much less than previously thought, and the amount of ice on the planet exceeds all guesses. Also, the lower layers of the atmosphere of Pluto, called the troposphere, are much smaller than expected.
Satellite Charon
Measurement of the size of the planet was carried out for decades due to problematic factors of the atmosphere. Observing the New Horizons, observing Charon’s satellite, confirmed the previous estimate of 1208 km (or 751 miles) over the entire surface of the object.
The Lorry apparatus also managed to get closer to two satellites of Pluto - Nyx and Hydra.
"We knew that from the moment when we developed a motion project for vehicles, we had the opportunity to study two small moons in detail just a few days before the closest approach to orbit," said scientist Alan Stern, the principal investigator at the New Horizons project. from Southwestern Research Institute in Boulder, Colorado. "Now our objects are deeply influenced by Pluto, so the time has come." Nyx and Hydra were discovered by the Hubble telescope in 2005. Even for Hubble, they were flashes of light, and this is how they looked for New Horizon during the last week of their mission with Pluto. Now the latest images made by LORRI show them not as points, but as full moons that can be measured. Nyksta’s size is estimated at about 35 km (or 20 miles) over the entire surface, and the Hydra is 45 km (or 30 miles). Such large sizes push scientists to the conclusion that the size of a huge area is related to the amount of ice on their surface.
What about the other moons of Pluto - Kerber and Stix? They are much smaller and less dense than Nikta and Hydra, so it is quite difficult to measure them.
But soon, when the New Horizon will pass close to their orbit, it will measure the approximate dimensions and send data to Earth, thereby scientists will determine specific figures.
