NASA’s Parker Solar Probe is on track to make history with the closest-ever approach to the Sun, as it plunges into the star’s outer atmosphere, enduring extreme temperatures and radiation.
The spacecraft, which launched in 2018, is set to reach its record-breaking closest point to the Sun on Christmas Eve, coming within 3.8 million miles (6.2 million kilometers) of the Sun’s surface. While this may seem far, NASA’s Nicola Fox puts it into perspective: “We are 93 million miles away from the Sun, so if the Sun and Earth were a meter apart, Parker Solar Probe would be just four centimeters from the Sun—that’s incredibly close.”
During this flyby, the probe will face intense heat, with temperatures reaching up to 1,400°C (2,500°F), as well as extreme radiation that could damage its electronics. However, it is protected by a 11.5 cm (4.5 inches) thick carbon-composite shield designed to withstand such conditions. The spacecraft’s strategy is to make the close pass quickly, traveling at speeds of 430,000 miles per hour—faster than any human-made object before it.
While the probe’s closest approach is a major milestone, the real goal of this daring mission is to unlock some of the Sun’s long-standing mysteries. Scientists hope that by passing through the Sun’s outer atmosphere, known as the corona, they can uncover why it is millions of degrees hotter than the surface of the Sun itself, which is around 6,000°C. Dr. Jenifer Millard, an astronomer at Fifth Star Labs, explained, “The corona is really, really hot, and we have no idea why.”
The mission also aims to improve our understanding of solar wind, the stream of charged particles that erupts from the corona and can impact Earth’s magnetic field. When these particles interact with the atmosphere, they create auroras, but they can also disrupt electronics, power grids, and communication systems. Understanding these phenomena is crucial for safeguarding technology on Earth.
As the spacecraft will be out of communication with Earth for several days during its flyby, NASA scientists are anxiously awaiting a signal, expected on 28 December at 05:00 GMT, to confirm if the probe has survived its fiery close encounter with the Sun. Dr. Nicola Fox, NASA’s head of science, admitted feeling nervous but expressed confidence in the spacecraft’s resilience. “It’s a tough, tough little spacecraft,” she said, noting that the team had designed it to withstand these extreme conditions.
If the Parker Solar Probe successfully completes this challenge, it will continue its mission, providing valuable data about our Sun for years to come.
