Think the summer sun has been hot for you? Parker Solar Probe, NASA’s newest spacecraft, has you beat.
On Saturday, the Parker Solar Probe will then begin a long journey to the Sun, eventually flying closer to the Sun than any other spacecraft in history. It will arrive within 3.8 million miles of the solar surface. If Earth was at one end of a yard-stick and the Sun on the other, Parker Solar Probe will make it to within four inches of the solar surface.
Zooming through space in a highly elliptical orbit, Parker Solar Probe will reach speeds up to 430,000 miles per hour. That’s fast enough to get from Philadelphia to Washington, D.C., in a second. During its seven-year mission, Parker Solar Probe will complete 24 orbits of the Sun.
But getting there is tougher than you might think.
Why? Here’s what NASA says:
The Sun contains 99.8 of the mass in our solar system. Its gravitational pull is what keeps everything here, from tiny Mercury to the gas giants to the Oort Cloud, 186 billion miles away. But even though the Sun has such a powerful pull, it’s surprisingly hard to actually go to the Sun: It takes 55 times more energy to go to the Sun than it does to go to Mars.
The answer lies in the same fact that keeps Earth from plunging into the Sun: Our planet is traveling very fast – about 67,000 miles per hour – almost entirely sideways relative to the Sun. The only way to get to the Sun is to cancel that sideways motion. Since Parker Solar Probe will skim through the Sun’s atmosphere, it only needs to drop 53,000 miles per hour of sideways motion to reach its destination, but that’s no easy feat. In addition to using a powerful rocket, the Delta IV Heavy, Parker Solar Probe will perform seven Venus gravity assists over its seven-year mission to shed sideways speed into Venus’ well of orbital energy.
These gravity assists will draw Parker Solar Probe’s orbit closer to the Sun for a record approach of just 3.83 million miles from the Sun’s visible surface on the final orbits. Though it’s shedding sideways speed to get closer to the Sun, Parker Solar Probe will pick up overall speed, bolstered by Sun’s extreme gravity – so it will also break the record for the fastest-ever human-made objects, clocking in at 430,000 miles per hour on its final orbits.
Wait?! Why Won’t the Parker Solar Probe Melt?