In 2018, NASA launched the Parker Solar Probe to collect data on the star that gives us life.
In addition to getting unbelievably close to the Sun -- only 15 million miles away, the solar probe is also the fastest man-made object ever.
The Parker Solar Probe was the first initiative to study solar energetic particles (SEP) and solar winds up close. Let’s take a look at some of the probe’s fascinating discoveries.
What Are Solar Winds and SEPs?
The intense heat from the Sun splits the hydrogen and helium atoms into free electrons and ions, known as plasma. This constant stream of ionized plasma along with the Sun's magnetic field flows through our entire solar system and is known as the solar wind.
Solar winds originate in the corona, the outermost part of the Sun's atmosphere, and travel at speeds of 200-500 miles per second. Fortunately, our Earth's magnetic field shields us by redirecting the gusts of particles around our planet.
Solar energetic particles (SEP) are high energy particles from the Sun -- such as electrons, protons, and heavier ions, that travel close to the speed of light. These rare outbursts originate at the site of an existing solar flare or as a result of shock waves from a Coronal Mass Ejection (CME) -- read our earlier article here.
These SEP particles can reach the Earth within an hour, disrupt communication and power, and pose a threat to satellites and astronauts in orbit.
The Probe's Findings
Scientists had believed until now that solar winds travel in straight lines from the Sun, based on observations from the Earth.
However, the probe has shown that solar winds are anything but uniform, with sudden turbulence and changes in magnetic fields. The probe also recorded a phenomenon known as switchbacks -- zig-zag patterns where the charged electrons and magnetic field lines turn towards the Sun and flip back again.
With Parker's help, scientists hope to understand how solar winds originate and flow out from the Sun's corona. It is well known that the Sun rotates as it releases the hot plasma, and these circular winds change to linear winds as they get further from the Sun. As Parker gets closer, scientists will be able to see how turbulent the solar winds get, and the distance at which they become linear.
Scientists have also long imagined a dust-free zone around the Sun, and the Parker Solar Probe found evidence supporting this. It is known that dust particles exist in space because they reflect visible sunlight. The Parker Solar Probe verified the belief that the Sun vaporizes cosmic dust particles because of its intense heat. In fact, there is a 3.5 million mile (or 5.6 million kilometers) dust-free zone circling the Sun.
Why is this important? The data from Parker enables researchers to better understand the impact of solar activity on space weather, recognize patterns of severe solar storms, and develop ways of protecting spacecraft and astronauts. By January 29, 2020, the probe will get even closer to our star and hopefully, reveal more secrets.
Sources: NASA, skyandtelescope, NYTimes, Nature