At 3:31 a.m. on Sunday, NASA’s newest spacecraft launched from Cape Canaveral, Florida.

A hot ticket: The probe is on a nearly seven-year mission that will take it closer to the sun than any other spacecraft has yet traveled. It will study the sun as never before, giving us clues into how and why our closest star behaves the way it does.

By the numbers: The probe will get to within 3.9 million miles of the sun’s surface and will become the fastest-traveling spacecraft to date, hitting speeds of 430,000 miles per hour. On its close approach, it will face temperatures of nearly 2,500 degrees Fahrenheit.

Why it matters: There is still a lot we don’t understand about the sun. The probe’s data will allow researchers to study the source and properties of solar wind, which can disrupt satellites and astronauts, as well as some long-debated mysteries about the heat of the sun’s corona.