Brigade XO wrote:At this point all Manticore and Torch really know is that Harvest Joy did not come back through the wormhole and nobody has heard anything from there from any other place. There is at least one wormhole which had been dubed a "killer" from which nothing has returned. Nobody is looking at sending another ship -of any kind- through this one at the present time.
Amoung the scenarios mentioned in the book is that it is POSSIBLE (but we know different) that the Harvest Joy either came out with damage which is keeping them from going anywhere, especially back through the wormhole. An alternative is that while they may have hyperspace ability, the other end of this wormhole may be so far away from anything in known space that they are going to have to travel for YEARS to get back to Human civilization. There is also the possibility that they ended up so far away that they can't find a reference point or two to let them even start to travel in the direction which may take them to human space.
JohnRoth wrote:This doesn't make astrographic sense. As long as you can see several of the closer galaxies (e.g. Magellenic Clouds), and have the ability to measure arcs between known reference points in them to fractional sub-second of arc precision, you can locate yourself within the galaxy.
It's called triangulation. In case you're wondering about how far triangulation can take you - I've seen a press release in the last couple of weeks where someone has extended Hubble's ability to triangulate out to around 10,000 ly with some very clever image analysis. They're proposing using it to nail down the distance to a number of Cephid variables to refine the cosmological distance ladder.
Ordinary ships wouldn't carry sensors with the needed precision, but the Harvest Joy certainly did. Or if it didn't, someone should sue the designers.
Tenshinai wrote:It makes perfect sense, under certain conditions. Rare but not impossible conditions.
Like having all the regular primary navigation stars hidden by other stars or stellar objects.
Because no, you don´t generally just try to match up a 3D stellar map with everything you can see, because that isn´t very effective.
Instead you try to find specific stars that you can positively identify regardless of your position in relation to them.
Or you could be on the inside of a gaseous area, or such an area could hide or distort all stars you have properly mapped.
Or the wormhole could be a major anomaly and put you REALLY far away.
OK, let's take this apart piece by piece. First, the point I was trying to make is that you
don't start out by trying to locate "beacon" stars. That takes way too long because you've got to look at a lot of stars and make spectroscopic measurements. You start by trying to localize where you are
first, and then refine it by locating those "beacon" stars.
You start with the Milky Way - that's obvious from anywhere and it gives you an immediate orientation. Then you look for the Magellenic clouds. They ought to be clearly visible from anywhere in the galaxy - they're big, they're bright, and they're visible by naked eye.
Once you've got yourself localized and oriented, you can decide which "beacon" stars to look for, and you know the general direction, usually to within a couple of degrees. If your sensors have enough precision, you probably don't need to do spectroscopic analysis: most of the "beacon" stars will be the only really bright star of that color in the expected patch of sky. Some more angular measurements, a little bit of trigonometry, and there you are.
Total elapsed time, given the appropriate instruments, computer support and references? About five seconds.
So why does just about everyone start off with the "beacon star" thing?
It's tradition! And that tradition most likely started before the astronomical community realized that these fuzzy patches were outside of our own galaxy!
Yes, it's possible you've wound up in a dusty area. You survey what you can see so you can get back to the wormhole terminus, then move a couple of dozen light years to see if you can find a clear area to locate yourself. Lather, rinse, repeat.
Or else you've been equipped with a set of infra-red sensors in anticipation of exactly this situation.
There are some other special cases, but there aren't any that can't be solved by one of those strategies --- assuming they're solvable at all. If your hyper generator failed, or you came out next to a black hole, white dwarf or pulsar or inside of a hypergiant, you've got more serious problems than figuring out your location.