The sun holds countless mysteries, some of which are likely to remain unanswered. Yet we are now one step closer to understanding the star at the center of our solar system, thanks to the Parker Solar Probe, which recently completed its closest-ever solar approach.
At its nearest point, on Christmas Eve, the NASA spacecraft passed within 3.8 million miles (6.1 million km) of the sun’s surface, yet survived its close encounter and appears to be operating normally. Late on Thursday, December 26, the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, received a beacon tone signaling that the probe was back in communication after a plunge into the sun’s outer atmosphere, also known as the corona.
Incredibly, the probe was able to withstand extreme radiation and temperatures exceeding one million degrees Fahrenheit. Thanks to the low density of the corona, the heat shield “only” became heated to around 1,800 °F (980 °C) thanks to its rapid speed and 4.5-inch-thick layers of carbon composite foam, carbon plates, and white ceramic paint. Due to the sun’s gravitational pull, the probe, which is roughly the size of a car, reached an incomprehensibly fast speed of 430,000 miles per hour (690,000 km/h), setting a record for a human-made object. For reference, if you could somehow fly that fast, you could get from London to New York in less than 30 seconds.
Scientists hope that the data collected by the Parker Solar Probe will help shed some light on the longstanding mystery of why the sun’s outer atmosphere is far hotter than its surface. They also hope to learn more about the origin of the charged particles streaming from the Sun into space, known as solar wind.
Although passing by the sun is nothing new for the Parker Solar Probe (it had already done this 21 times), the Christmas Eve flyby was the closest it has ever gotten to the solar surface. It will remain in its current oval-shaped orbit for the rest of its mission.
Kissing the sun:
- By comparison, Mercury orbits the sun at a distance of around 36 million miles. The Earth orbits the sun at around 93 million miles.
- The Parker Solar Probe was launched in 2018. It completed seven flybys of Venus in order to achieve its optimal orbit around the Sun.
- The mission control team hopes to receive a more detailed status update from the probe on January 1 and the complete data and images by late January, when it has moved farther away from the sun.
