Suddenly the Imperium of Mankind seems a lot less impressive...

[Xenith]

One Million inhabited worlds =/= One million potentially inhabitable worlds.

There are still worlds in the Imperium that, while habitable, are uninhabited.

[Wolfshade]

Or are inhabited by non-Imperials, or are still cut off from the rest of the imperium by warp storms since the age of darkness

[YorkNecromancer]

It's like the Soviet Union suddenly shrinking to the size of Monaco.

There's a reason why:

[url]http://tvtropes.org/pmwiki/pmwiki.php/Main/ScifiWritersHaveNoSenseOfScale[/url]

[fuzzbuket]

my problem with imperial maps is the fact that all the space maps are 2d. just let that sink in, the imperium of man is like a frisbee. why cant it be spherical ?

[DWest]

Actually, the 2d makes sense; if you look at a spiral galaxy like the Milky Way, once you zoom out far enough to have the whole thing on a single page, the thickness of the disc becomes insignificant, until you get to the very core, a.k.a the place where the big scary black hole driving the thing is.

[Mr Mystery]

Apologies, but replied = TLR.

Billions of worlds the same size does not equate to billions of inhabitable worlds!

[walrusman999]

One would think that with the technology they have they could potentially colonize worlds that arn't necessarily inhabitable by manipulating their atmosphere to make it habitable. But then there is the fact that the IoM has a horrible problem with logistics and so inhabiting new worlds is potentially impossible since they probably couldn't pull the resources together to inhabit a new world.

Also I agree that they should stop Exterminating every planet that isn't already controlled by the IoM.

For the Emperor!

[Dlatrex]

Ugh. Should I really try to defend the indefensible?

Let's take a look at some star-charts of questionable validity. The modern imperium of man is of course centered on Terra, and broken up into 5 segement(um)s. Now Ultima Segmentum is the most sparsely populated of the imperial segements (with the notable cluster of Ultramar) so let's ignore it for the moment. With just the remaining 4 segements, the imperium 'covers' roughly 31% of the galaxy by area. We might assume Ultima segmentum is only populated at 1/5th the density of the remaining 4 segments (generous), which means we’re probably looking at an equivalent territory of about 42% of the galaxy. We’re already down 7.14 Billion worlds! Making progress!

[Dlatrex]

So right now the Imperium of Man looks like it covers between 40%-70% of the galaxy by area. So who does it get to share all this territory with? Let's look at the Xenos/Heretic's maps.






These are deceptive as mostly they show imperial ‘incursions’ with each of the threats. Chaos and Orks seem to compete for most populous, but given that Orks seems to move much more slowly than the other empires, they are likely the largest owner of worlds outside the imperium.

Let’s see if we can Math-Fu the remainder:

Start with 7.14 billion worlds:
Assume that right off the bat ½ of them are undiscovered/uninhabited, stuck in the eye of terror, or inhabited by some other xenos not mentioned.

3.57B

Assume that the Imperium shares 50% of its 'sovereign area' evenly with the 5 intruding powers (Chaos, Tyranids, Necrons, Orks, and Eldar protected/exodite worlds)

2.14B

And take into account the standard error at the Administratum (20%)

1.71 Billion

…

Ok I tried. Even being very generous it is likely that the Imperial almanac is short it’s estimate by a factor of 1,000 given what we now know about the galaxy. Let’s hand-wave this and assume that over the next 40 millennia warp-storms destroyed 95% of the habitable worlds.

OH and as a PS, I did not forget about the Tau: at 300 light years across, the Tau Empire covers roughly 0.000330579% of the Galaxy.

[dark messenger]

Let's not forget that even at the very height of it's power, when Emperor and his Primarch sons were stomping on aliens, most of the Milky Way galaxy (as we know it) remained well outside the Imperium's borders.
Do not think of the Imperium as a connected web of worlds all extending to Terra. It's more strong clusters of inhabited space that withhold against the rest. Without warp travel and the Astronomican there would be no Imperium.

Kinda makes it more impressive what the xeno races have managed to achieve! Really makes humanity look bad (and that's me saying that as an avid IoM supporter)
Consider also that the IoM has the technology to "Terraform" planets and regularly do. As many planets suffer Exterminatus so an equal amount are discovered or graded and put to use as fully functioning worlds of the Imperium.

If it was comparable to the real life galaxy, then I have to say that it's still impressive for humans if we do indeed achieve what was accomplished in 40K. If we get cracking on it, we should be colonising our own Sol system within the next few centuries...
So where's the Emperor hiding then?