I'll try to suggest some thoughts on it if I understand the gist of your question.

Flying 'blind' in space and expect to hit your target planet/moon would for all practical purposes result in a deceased astronaut. 

So you find yourself travelling in space at 25-50 Km/sec.? toward Saturn with short range radar and no radio contact, no inertial navigation, no (DSN) deep Space network, no laser range finder, no on-board computer. 
With a Sextant, on-board celestial charts, astronautic tables, dead reckoning and a set of functioning eyeballs would not be enough. By the time you've done the necessary calculations you would most likely overshoot your target orbiting endlessly within the solar system till you run out of on-board oxygen or get caught in a 'gravitational well' at the end of which would be a 'hard rock' impact normally reserved for comets and meteorites. Even with the short range radar this might not offer avoiding a space object trajectory of a potentially lethal collision with your spacecraft.

I think Apollo 13 (maybe other instances) had to use a sort of 'pip' screen in order to gauge Earth re-entry window but they had considerable assistance besides the astronauts were trained for contingencies. 

Short answer: doing math, a precise telescope, allot of triangulations and knowing where you started and where are you going.


Space is actually a pretty navigation-friendly environment as there is likely nothing nearby. Remember, in space, think vectors and vectors are (supposed to be anyway) easy to calculate and don't change much.

There is also one or two very strict points of reference that can be handy if you recognise it: the sun of the solar system. Having two stars is actually very handy, as their distance is unlikely to change much. Gas giants may be also of help. If you have high-detail and precise IR and radiation sensors, then you can also establish further points of reference, like a gas giant.

If you are able to figure out the distance of the two suns, you will be quickly be able to find out your own as well as your speed. Heck, if you have enough knowledge and time for the mathematics, you can also figure out the solar system a bit, like the mass of the suns and planets you use as point of reference. This is assuming you don't know where you are but have time on your hands.

Radar would actually be useless, unless you are very near a planet. It's not due to the time it takes to go back and forth, but because the radar will quickly disperse by the time it gets back to you. The most useful application I can think of for a powerful radar, is adjusting orbit. I think.

This section of Atomic Rocket may be of help: http://www.projectrho.com/rocket/rocket3af.html

Popular Sci-Fi of the day showed "Dan Dare" flying spaceships around by the seat of his pants like a crop duster pilot would but I would imagine it is a lot harder than that, especially if you have to account for every M/s of your available deltaV.

Many of those authors of the time (and today's time especially) underestimated or not given too much thought of the complications of navigation. Remember, imagining is not quite as meticulous as actually making it. Besides that, navigation is actually quite a boring task. Zapping space bugs is far less so, and the authors have to make a living.

Furthermore, most sci-fis have some kind of FTL drive that can actually simplify matters considerably.


(I am guessing the use of an almanac plus sightings of visible planets plus atomic clock, but It would all be pretty hard, especially without a computer)

Actually, you CAN'T go without a computer. Even if the very first manned spaceflights, there were primitive and simple (relative to today's) computers that were at hand, and flight control had access to allot of brainpower and supercomputing.

The mathematics of precise orbit computation is very challenging, and I have definately not mastered it (you could get a masters degree in mathematics just for the purpose!) I have looked at several programs that can do the job, such as STK (satellite toolkit) but the $10,000 package price has thus far deterred me from running out with my credit card!... smile

I recall that there are two programs out there for orbit calculations. Look around in the link I provide for info, in the "suggested reading section".

-- Edited by Andrew at 21:59, 2008-01-17

EDIT: if you would like to learn and try spaceflight for yourself (virtually of course) try this software: http://orbit.medphys.ucl.ac.uk/orbit.html

I myself haven't got around the learning curve and deceided to not meedle until the next update, whence I may finally have a chance to try out my X52 to its full potential.


-- Edited by Andrew at 22:03, 2008-01-17