Getting Close to the Sun

December 9, 2017
Jeffrey Kluger for TIME, adapted by TIME for Kids editors
CLOSE ENCOUNTER An illustration shows the Parker Solar Probe approaching the sun.

No spacecraft will ever land on the sun. Why? The sun is a flaming ball of gas. The gas reaches thousands of degrees Fahrenheit (F). But next year, a ship from Earth will fly closer to the sun than any ship before it. The mission is a big development for scientists. It could also be a big deal for everyone else.

In September 2018, NASA plans to launch the Parker Solar Probe. It will travel nearly 90 million miles. It will fly within 3.8 million miles of the sun. Within two months of launching, the probe is expected to reach the sun’s corona. That’s the sun’s outer atmosphere of fiery gases.

It will cost $1.5 billion to build, launch, and operate the unmanned ship. The mission will help us better understand our sun and other stars. The closest star system to ours is 24 trillion miles away. But the sun is just 93 million miles away. That is well within our reach.

A Speedy Journey

The probe will use Venus’s gravity to edge closer to the sun. Ultimately, the ship will be so close that it will travel around the sun in just 88 days. That is a quick trip. It takes Earth 365 days to orbit the sun.

Temperatures in the corona can reach millions of degrees. The probe will remain in regions where things get no hotter than 2,500°F. That’s still hot for a spacecraft. A 4.5-inch-thick carbon-composite heat shield will protect its camera and scientific instruments.

A Star Quest

Our sun is special to us. But as a star, it’s rather common. The better we understand how it works, the better we understand all stars of its size and color.

Perhaps most important is what the probe may reveal about solar storms. They can cause trouble. During solar storms, charged particles stream through the solar system. They can disable communications satellites. They can also shut down electrical grids. One study says that a powerful solar storm could cause up to $2 trillion in damage in the U.S. alone.

Understanding solar storms might allow us to predict them and protect ourselves. That could make even a mission with a billion-plus price tag one of NASA’s great bargains.