One Simple Reason Why Touching The Sun Is So Hard
“It doesn’t simply take a suite of clever instruments to measure the Sun up close, although the Parker Solar Probe has those. It isn’t enough to have a thick, carbon-composite shield to withstand the incredible radiation and temperatures present in close proximity to the Sun, although the Parker Solar Probe has those, too. It also requires an incredibly complex, intricate plan to insert yourself into a stable orbit that’s capable of bringing you closer to the Sun than anything else ever has before.”
If there’s one law of physics that most people know, it’s Newton’s first law. Objects at rest remain at rest, and objects in motion remain in uniform motion, unless they’re acted on by an outside force. This applies not just to straight-line motions, but to orbiting motions as well. It isn’t just momentum that’s conserved in physics, but angular (or rotational) momentum, too. In order to touch the Sun, the Parker Solar Probe has to somehow get rid of a tremendous amount of angular momentum, and rockets alone aren’t powerful enough to do it. The trick? You have to use the other planets in the Solar System, and give up your angular momentum to them. The Parker Solar Probe will pass close by Venus a record seven times in order to do this, coming within less than 4 million miles of the Sun when they’re all over.