The Oort Cloud is the most distant region in our solar system, and it's jaw-droppingly far away,extending perhaps one-quarter to halfway from our Sun to the next star.
To appreciate the distance to the Oort Cloud, it’s helpful to set aside miles and kilometers and instead use the astronomical unit, or AU — a unit defined as the distance between Earth and the Sun, with 1 AU being roughly 93 million miles or 150 million kilometers.
For comparison, Pluto's more elliptical orbit carries it between about 30 and 50 astronomical units from the Sun. The inner edge of the Oort Cloud, however, is thought to be located between 2,000 and 5,000 AU from the Sun, with the outer edge being located somewhere between 10,000 and 100,000 AU from the Sun.
If those distances are difficult to visualize, you can instead use time as your ruler. At its current speed of about a million miles a day, NASA's Voyager 1 spacecraft won't enter the Oort Cloud for about 300 years. And it won’t exit the outer edge for maybe 30,000 years.
Even if you could travel at the speed of light (about 671 million miles per hour, or 1 billion kilometers per hour), a trip to the Oort Cloud would require that you pack for a lengthy expedition.
When light leaves the Sun, it takes a little over eight minutes to reach Earth, and about 4.5 hours to reach Neptune’s orbit. Just under three hours after passing Neptune’s orbit, the Sun’s light passes beyond the outer edge of the Kuiper Belt.
After another 12 hours the sunlight reaches the heliopause, where the solar wind — a torrent of charged particles flowing away from the Sun at about a million miles per hour (400 kilometers per second) — smooshes up against the interstellar medium. Beyond this boundary is interstellar space, where the Sun’s magnetic field holds no sway. The sunlight has now been traveling away from the Sun for about 17 hours.
Less than one Earth day after leaving the Sun, the sunlight has already traveled farther from the Sun than any human-made spacecraft. Yet somehow it will be another 10 to 28 days before that same sunlight reaches the inner edge of the Oort Cloud, and perhaps as much as a year and a half before the sunlight passes beyond the Oort Cloud’s outer edge.