A spacecraft is about to fly into the sun’s atmosphere for the first time

Almost no one ever writes about the Parker Solar Probe no longer.

Of course, the spaceship got some attention when it was launched. It is, after all, the fastest object that man has ever built. At its maximum speed, goosed by the gravitational pull of the sun, the probe reaches a speed of 430,000 miles per hour, or more than one-sixth of 1 percent the speed of light. That kind of speed will get you from New York City to Tokyo in less than a minute.

And Parker Solar Probe also has the distinction of being NASA’s first spacecraft named after a living person. At the time of its launch, in August 2018, physicist Eugene Parker was 91 years old.

But in the six years that the probe has been zipping through space and flying from the sun? Not so much. Let’s face it, the astrophysical properties of the sun and its complicated structure are not something that most people think about every day.

However, the small probe – mass less than a metric ton, and its scientific load is only about 110 pounds (50 kg) – is about to make its star. Quite literally. On Christmas Eve, the Parker Solar Probe will make its closest approach to the sun. It will be just 3.8 million miles (6.1 million km) from the sun’s surface, flying into the solar atmosphere for the first time.

Yes, it will be quite warm. Scientists estimate that the probe’s heat shield will withstand temperatures of more than 2,500 degrees Fahrenheit (1,371 C) on Christmas Eve, which is almost the polar opposite of the North Pole.

Going straight to the source

I spoke with NASA’s chief science officer, Nicky Fox, to understand why the probe was tortured like this. Before moving to NASA headquarters, Fox was the project scientist for the Parker Solar Probe, and he explained that scientists really want to understand the origins of the solar wind.

This is the stream of charged particles emanating from the sun’s outermost layer, the corona. Scientists have wondered about this particular mystery for more than half a century, Fox explained.

“Simply put, we want to find the birthplace of the solar wind,” he said.

In the 1950s, before we had satellites or spacecraft to measure the properties of the sun, Parker predicted the existence of this solar wind. The scientific community was quite skeptical about this idea – much ridiculed Parker, in fact – until the Mariner 2 mission began to measure the solar wind in 1962.

When the scientific community began to embrace Parker’s theory, they wanted to know more about the solar wind, which is such a fundamental component of the entire solar system. Although the solar wind is invisible to the naked eye, when you see an aurora on Earth, this is the solar wind interacting with the Earth’s magnetosphere in a particularly violent way.