Pluto, the dwarf planet named after the Roman god of the underworld, is the furthest from the Sun and sits at the darkest reaches of the solar system. The dwarf planet has been in the news a lot lately as new information about Pluto has slowly trickled into NASA and its astronomers. With these new discoveries about Pluto’s atmosphere and land mass, scientist are examining if Pluto has ever been a host for water or living organisms.
Pluto was discovered by Clyde Tombaugh in 1930. Pluto was initially labeled as the ninth planet from the Sun. Since 1992, the status of Pluto being a “planet” was called into question. This is due to several other planets of similar shapes and sizes discovered orbiting within the same area of Pluto. In 2005, the International Astronomical Union classified Pluto into the new category of “dwarf planet.” The dwarf planet has five equally dwarf moons that orbit its atmosphere: Charon, Styx, Nix, Kerberos, and Hydra. Gizmodo reports that in July 2015, the New Horizons spacecraft managed to reach Pluto on a ‘flyby’ mission and managed to observe Pluto, its moons, and obtain each of their measurements.
Earlier this year the Lunar and Planetary Sciences Conference revealed Pluto shrinks and expands its atmosphere over time. According to the Guardian, this is due to the arctic and tropic regions that cause drastic changes in the planet’s climate. When the New Horizons spacecraft flew by Pluto in August 2015, new details about the planet began to surface. At the conference, the biggest announcement came from MIT and the Southwest Research Institute. Their research reveals in addition to the arctic and tropic regions on Pluto, there is an exaggerated axial tilt. This tilt is what causes the planets’ climate and atmosphere to change over time, thus denoting the planet has seasonal changes just like Earth.
These radical changes to atmospheric pressure on the dwarf planet Pluto suggest dramatic changes to circulation in Pluto’s atmosphere. They could explain how haze works on Pluto and the rate at which the atmosphere is escaping. What’s more, high pressure is what allows certain elements, like nitrogen (which is common on Pluto), to take on a liquid state. This finding thus strengthens the suggestion that liquid nitrogen may have once existed on the surface.
Also at the conference, NASA researcher, Orkan Umurhan presented photographs of glacial activities including landforms, liquid flow, and erosion happening on the surface of Pluto. Umurhan has assessed two causes for this change in atmosphere
“it’s either a slow, gradual process, or it’s erosion caused by flowing liquid nitrogen—a scenario supported by the work of his colleagues. ”
National Geographic states that the New Horizons spacecraft has also found a spot of terrain that appears to have been shaped by a liquid, and this is in the formation of lake. This formation is 20 miles long and it is not clear if the liquid under the surface is nitrogen, H20, neon, molecular oxygen or helium.
It is baffling to scientists that liquid even exists on Pluto. Cnet confirms temperatures on Pluto’s surface to average -400 Fahrenheit. However, during the planet’s 248-year orbit around the Sun, Pluto is wetter at various points planetary rotation. This proves that Pluto is not always cold. The last time temperatures were above zero is around 800 million years ago, suggesting the dwarf planet has now entered a phase of extreme change.
National Geographic also reports the New Horizons trip has been extended, but it still has a long way to go. Pluto, its Moons, and the Kuiper belt are soon to be explored extensively. As new information is received by NASA, more will be revealed to the public. However, NASA may not anything new until 2019 (Pluto is 4.67 billion miles from Earth). What is next for the dark, cold, dwarf planet? We will find out soon.
[Photo by NASA/JHUAPL/SWRI via Getty Images]