A spacecraft has finally gotten close enough to the sun to gather clues about some lingering questions. //

It sounds counterintuitive, but it’s actually harder to reach the sun than it is to leave the solar system altogether. //

“To get to Mars, you only need to increase slightly your orbital speed. If you need to get to the sun, you basically have to completely slow down your current momentum,” //

No existing rocket technology is powerful enough to cancel out the Earth’s motion like that, so the Parker probe is getting an assist from other planets. The spacecraft has been flying way out to Venus and looping around, trimming its orbit each time to shed some of the Earth’s momentum and bring itself closer to the center of the solar system.