The dwarf planet Pluto’s icy “beating heart” of frozen nitrogen controls its winds and possibly other features on the surface, according to research released by NASA.
The NASA study was published in the December 2019 Journal of Geophysical Research, and builds off of data taken from NASA’s 2015 New Horizons mission, which captured footage of the heart-shaped ice structure named Tombaugh Regio on the surface for the first time.
The study found that frozen nitrogen – in the shape of a heart – covers Pluto’s surface, and a thin layer of the nitrogen turns into vapour during the day.
At night, the vapour is again frozen into ice, which pumps nitrogen winds around the surface, and gives rise to the sequence being labeled a “heartbeat” due to the shape of the structure and cyclical nature of the event.
Researchers ran several simulations of the phenomenon and found that the “heartbeat” pushes the nitrogen winds in the opposite direction that the planet is spinning, known as “retro-rotation.”
Because Pluto orbits far from the sun, its seasonal cycle is much longer than that of Earth – with one Pluto year approximately equivalent to 248 Earth years – according to the study. The surface of Pluto receives very little energy from the sun because of its distance, which results in slow surface events – all of which had to be accounted for when researchers did their simulations, which had their calculations spanning several Pluto years.
The study posits that the unique phenomenon of retro-rotation is the cause of “dark wind streaks….and differences in ice composition and colour” that have been observed in the Sputnik Planitia basin and other areas on Pluto’s surface.
Researchers noted in their study that their work confirms that despite a “frozen surface and tenuous atmosphere, Pluto’s climate is remarkably active.”