Launched in 2018, NASA's spacecraft will spend the next 6 years in the star-king's orbit – to catch his behavior very closely.
By Guilherme Eler
Dec 7, 2019, 4:48 pm
Built to have high heat and radiation resistance, the Parker spacecraft left Earth in August 2018 with the simple mission of “touching the sun” – or rather flying over our largest star in unprecedented proximity. In a maneuver made a few months ago, the vehicle was at a distance of 24 million kilometers from the solar surface, enough to complete the feat. And also to provide unprecedented information to astronomers. The first findings of the probe were compiled in four articles, published in the journal Nature last Wednesday (4).
There are two main goals for the Parker mission: to explain the nature of the solar winds and to give clues as to why the temperature of the sun's extended atmosphere, also known as the corona, is so much higher than its surface.
Solar winds are nothing more than an orderly flow of ionized particles (read protons and electrons) emitted by the sun. These particles have very large energy, capable of breaking the star's gravity and falling into space – even reaching Earth. When they show up around here, they can cause phenomena like aurora borealis and even damage satellite communication, GPS and power transmission networks.
About the origin of the solar winds, Parker discovered something interesting: they don't always come from the same point as the sun. Astronomers knew in advance that what we call the solar wind is actually a mixture of two types of "gale." There are the fastest winds – which can reach 700 km / second and originate from the "coronal holes", species of volcanoes in the region of the poles that are throwing particles of the type – and the slowest, whose speed is 500 km / second. , and, until then, had unknown origin. According to Parker data, slow solar winds come from holes in the Sun's “Ecuador region”. These solar belt structures had never been observed by scientists.
Also according to Parker information, instead of simply being radiated into space, solar wind particles are released by the sun through constant explosions. This brings us to the question of the solar atmosphere, and its extremely hot nature. As a rule, the temperature of a celestial body is usually higher according to the proximity of the nucleus.
But that's not the case with the sun: while thermometers can exceed 5.500 degrees Celsius on the surface, the corona is much warmer. It is estimated that, over there, the temperature will reach millions of degrees. What Parker's information indicates is that the fact that the solar wind is blown up as explosions directly into the atmosphere, which makes it absorb large amounts of energy, may explain the temperature difference.
Another interesting aspect detailed in the studies, finally, was the unexpected amount of cosmic dust detected in the solar corona region. This rock dust, which generates an increasingly dense cloud according to its proximity to the Sun, is believed to be nothing but remnants of asteroids and comets, dissolved by passing too close to the star. The closer to the star, the thinner the cloud of debris became.
Although Parker's initial Icarus flight was a success, it should not stop there. The spacecraft keeps spinning around the sun with an irregular orbit – which sometimes takes it farther from the sun and sometimes brings it closer – and should stay that way for the next six years. According to NASA, the mission has so far accomplished only three of the 24 planned stages. In the next few chapters of the solar corona expedition, Parker is expected to be a mere 6 million kilometers from the Sun's surface – enough, it is hoped, to further expand how much we know about our nearest star.
“Watching the sun closely, rather than just studying it from a gigantic distance, has provided unique insights into important solar phenomena – and how they affect the earth. This gives us ammunition to understand stars from other galaxies as well, ”said Thomas Zurbuchen, head of the science division at NASA's Washington headquarters, in statement. "It's just the beginning of an exciting phase of heliophysics (solar physics study), with Parker at the forefront of new discoveries."