I'm a screenwriter and I'm currently writing a sci-fi short about a journey from Earth to Pluto.

The title of the script is "Three Billion Miles To Pluto" and i wanted to know if that was accurate. I've read that, at it's closest, it's around 2 billion miles from Earth...so I guessed that at some point in its orbit, it would be 3 billion.

But there's another factor...in the script, the ship (called "The Hades") makes a brief stopover at a research station in orbit above Mars, so I'm wondering if anyone could tell me if a journey from Earth (actually, the moon) to Mars to Pluto could still take place within a distance of 3 billion miles.

Thanks for the help...it's a small thing that the audience wouldn't notice, but I'd like to be as accurate as possible.

Pluto is 5,763,920,000 km (38.5AU) from the earth which is the same as 3,581,533,842.361. I am not sure if this is on Pluto's closet approach to Earth or not, but I would say that it probably comes closer at times making it fall within a three billion mile trip. I hope this helps.

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Pluto's orbit is inclined quite a bit from the orbits of the planets. Also it's more elliptical. That may be one of the reasons why it really is not a planet. Maybe it got captured somehow or it got perturbed a lot. It's awfully small. Its distance from the Sun (and the Earth) varies quite a bit, perhaps +- 25 percent. A couple decades ago it actually got inside the orbit of Neptune. Now Pluto's getting farther away and dimmer.

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Pluto is 5,763,920,000 km (38.5AU) from the earth which is the same as 3,581,533,842.361.

I presume you mean miles … Where did you get the original figure? (See below.) Right now Pluto is 32.0 AU from here, and 31.4 AU from the Sun.

BTW, aside from including units ;) it would be better to report the last figure as 3,581,530,000, as it’s a pretty safe bet that the trailing zeros in the original are ‘padding’. Giving a result to the 0.001 mile implies that the distance is known to within a ‘stride’, about five feet (1.6 m).

I am not sure if this is on Pluto's closet approach to Earth or not, but I would say that it probably comes closer at times making it fall within a three billion mile trip.

Yes, Pluto’s perihelion is 30.2 AU, or 2.76 billion miles.* But you only get an opportunity to catch it there once in 248 years; its average distance from the Sun is nearly 40 AU, 3.7 billion miles, and its aphelion is 48.5 AU, 4.58 billion miles.

@Vadakin, if you tell us in what year the story takes place, we may be able to estimate how far away Pluto is expected to be at that time. As for the stopover near Mars, a favourable situation of the planet—one that wouldn’t make for much of a detour—would arise every couple of years. Even in the worst case, though, the trip would only be lengthened (in distance) by something like 10%: the variation in Pluto’s distance will be the dominant consideration.

* According to NASA’s Planetary Fact Sheet.

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I don't have an exact year for the story though it's certainly no sooner than 50 years from now given that there is a launch site on Earth's moon and an orbital space station above Mars, and possibly a colony on the planet itself.

In terms of the technology, well the ship makes the journey in 10 months, so the ship is pretty fast and the crew spend most of their time in stasis.

The ship's engine is an "Ion Drive" but don't ask me how it works because I pretty much went with standard sci-fi where an Ion Drive is standard.

I kept the exact year vague for the purposes of the story, but I would say between 100 and 200 years from now.

The ship's engine is an "Ion Drive" but don't ask me how it works because I pretty much went with standard sci-fi where an Ion Drive is standard.

Lousy acceleration but economical for long hauls. If you land it on anything with significant gravity, it’ll never take off again without boosters. It would probably need auxiliary thrusters for getting in & out of orbit and other such manoeuvres. Unless ion-drive technology vastly improves beyond what is currently envisioned, of course.

I kept the exact year vague for the purposes of the story, but I would say between 100 and 200 years from now.

A little over a hundred years from now Pluto will be at aphelion, which means that it will approach us again over the following century. I figure the distance will become less than 3,500,000,000 mi. (making your title apt, taken to the nearest billion miles) sometime around 2190, remaining ‘within range’ for the next eighty years or so.

Lousy acceleration but economical for long hauls. If you land it on anything with significant gravity, it’ll never take off again without boosters. It would probably need auxiliary thrusters for getting in & out of orbit and other such manoeuvres. Unless ion-drive technology vastly improves beyond what is currently envisioned, of course.

Well it launches from the moon and *SPOILER* never actually makes it to Pluto, so i shouldn't have to worry too much about gravity

A little over a hundred years from now Pluto will be at aphelion, which means that it will approach us again over the following century. I figure the distance will become less than 3,500,000,000 mi. (making your title apt, taken to the nearest billion miles) sometime around 2190, remaining ‘within range’ for the next eighty years or so.

2217 AD then. Far enough into the future so that reaching Pluto within 10 months might be a possibility, without being too far into the future, with teleporters and warp drives. Thanks for the info.