Planetary Distances

[Starkers]

Hi, I don't post in Science and Technology very often but I had a question I was hoping someone could help with. Basically I'm wondering if there's any accessible resource that can advise of the distance between planets?

There's a lot of info on the distance between the Sun and the Earth and between the Sun and the other planets, but what I'm looking for is the distance between particular planets, specifically Mars and Uranus (it's for a writing project.) Obviously just subtracting the distance between the Sun and Mars from the distance between the Sun and Uranus wouldn't be remotely accurate due to the orbital position of the planets.

Just to further complicate matters ideally I'm looking for the distance between planets in sixty or so years but I'll take the position now if it's the best I can get.

I asked this question on Twitter and someone directed me here but I have no idea how accurate it is.

Any help would be really appreciated

 

[Kamen Rider Blade]

Wolfram Alpha is a legit source for math & science.

 

[Starkers]

Wolfram Alpha is a legit source for math & science.

Thank you. That's good to know.

 

[XCV330]

Long shot, but if you have a planetarium in your area, you could call the staff and ask. They almost certainly have access to Stellarium and can look it up quickly. Another option would be to just get Stellarium.

 

[Jedi Marso]

That's a dynamic question because the planets are always in motion around the sun, and the closer they are, the faster their orbits are. So on any given day, the answer to your question varies. With programs like Celestia you can choose an exact date and time, and it will position the planets where they will be. The you can zoom in to the location of one planet, focus on another, and it will give you the exact distance. It's been a few years since I used the software, and I can't remember if it gives the answer in miles or astronomical units- it may depend on scale. One astronomical unit (1 AU) is the Earth-Sun distance, or 93 million miles. IIRC, Celestia is freeware.

 

[Jedi Marso]

Actually, your question made me curious, because I used to use Celestia for just the same thing you asked about, when I was writing a book a few years ago. Like the Expanse, it used a lot of real-world distances and times, and I used a nomogram chart to calculate travel times based on constant accelerations and those distances.

Your question is easy to answer using Celestia: On this date and time, 2082, Mars and Uranus are 19.778 AU apart, or 1,839,354,000 miles apart. If you want that in KM, multiply the number of miles by 1.6. A radio signal travelling between Mars and Uranus at this time would take about 168 minutes to travel between the two, or 2.8 hours.

 

[Asbo Zaprudder]

One also has to factor in the position of the destination at the arrival time will be different from that at the start time. In The Expanse with the somewhat magical Epstein Drive, one can more or less just thrust constantly toward or away from the expected position with a turnover at midway. In real life, Hohmann transfer orbits, bi-elliptic transfer, low-thrust transfer, or the Interplanetary Transport Network (ITN) would have to be used.

 

[Starkers]

Long shot, but if you have a planetarium in your area, you could call the staff and ask. They almost certainly have access to Stellarium and can look it up quickly. Another option would be to just get Stellarium.

Thanks for this. I'll look that up.

That's a dynamic question because the planets are always in motion around the sun, and the closer they are, the faster their orbits are. So on any given day, the answer to your question varies. With programs like Celestia you can choose an exact date and time, and it will position the planets where they will be. The you can zoom in to the location of one planet, focus on another, and it will give you the exact distance. It's been a few years since I used the software, and I can't remember if it gives the answer in miles or astronomical units- it may depend on scale. One astronomical unit (1 AU) is the Earth-Sun distance, or 93 million miles. IIRC, Celestia is freeware.

Thanks for this. I think it's fair to say that I don't necessarily want something ultra accurate, but I don't want something that bears no relation to reality either.

Actually, your question made me curious, because I used to use Celestia for just the same thing you asked about, when I was writing a book a few years ago. Like the Expanse, it used a lot of real-world distances and times, and I used a nomogram chart to calculate travel times based on constant accelerations and those distances.

Your question is easy to answer using Celestia: On this date and time, 2082, Mars and Uranus are 19.778 AU apart, or 1,839,354,000 miles apart. If you want that in KM, multiply the number of miles by 1.6. A radio signal travelling between Mars and Uranus at this time would take about 168 minutes to travel between the two, or 2.8 hours.

That's reasonably similar to the figure Wolfram Alpha gave (admittedly I'd put 2070 in) but looks like getting Celestia and Stellarium as well might be useful. As well as needing to guestimate how long it would take a ship to reach Uranus the signal time for a radio message to travel between the two points will also be a factor.

One also has to factor in the position of the destination at the arrival time will be different from that at the start time. In The Expanse with the somewhat magical Epstein Drive, one can more or less just thrust constantly toward or away from the expected position with a turnover at midway. In real life, Hohmann transfer orbits, bi-elliptic transfer, low-thrust transfer, or the Interplanetary Transport Network (ITN) would have to be used.

I think this is the next thing to work out once I have an approximate distance. To be honest the meat of the story will be set on one of Uranus' moons, but again I want the journey there to reflect reality to at least some degree, even if it'll still be somewhat hypothetical situation. Definitely more Expanse than Star Wars.

 

[BK613]

I haven't checked but I wouldn't be surprised if Atomic Rockets had the math for planetary transfer orbits already set up on their website somewhere...

 

[Starkers]

I haven't checked but I wouldn't be surprised if Atomic Rockets had the math for planetary transfer orbits already set up on their website somewhere...

Thank you, definitely useful stuff here!

http://www.projectrho.com/public_html/rocket/spacemaps.php

http://www.projectrho.com/public_html/rocket/orbits.php

 

[BK613]

Thank you, definitely useful stuff here!

Yea, for those interested in the science-y side of science fiction, that website is a rabbit hole and a half.

 

[Starkers]

I really shouldn't' have looked while at work