Time for some answers. I'm not starting a separate thread as there is no identity to guess.
As far as possible I will compare the facts about the two and suggest astrological reasonings - but alternative or extended explanations are welcome. I'm going to use the 21.15 Chart for Gates
Appearance
Bill gates is stated to be 5ft 10, and of normal build ( although from pictures he seems to be slimmer now and when he was young than during his microsoft exec years). He has a roundish face. His hair is fairish with a possible hint of redness.
Mystery twin ( MT hereafter) is 2-3 incles taller, and very slim/lean with a lean face. Both have blue eyes. MT doesn?t wear glasses ( though I can?t recall if he has contact lenses). Quite intense eyes. Although Gates is fairer, MT is not particularly dark.
I take these differences to be generally indicative of their Ascendant. With Gates represented by his Cancer ascendant and perhaps the Moon in Aries, whereas MT is much more described by the Leo Ascendant with Jupiter rising - though there is not hint at all of any portliness due to Jupiter just height. I imagine that the Saturn square also contributes to the leaness, though why that means less weight rather than less height I am not sure. The Sun as Asc ruler also in Scorpio probably contributes to the intensity of the eyes etc.
Background
Gates family was upper middle class; his father was a prominent lawyer. MT?s family were probably more normal middle class, with a relatively confortable upbringing. Gates has 2 sisters. MT has one.
I am struggling to identify where I would find childhood conditions in the chart
Gates has 2 sisters. MT has one.
This should come from 3rd house but on that I woudl expect MT to have more siblings.
Health
As far as I am aware neither have had any significant health issues.
I presume the lack of aspects in MT'c chart from the 6th house ruler Saturn to Sun moon Mars and Mercury help this.
In Gates' chart the 6th hosue ruler is Jupiter and again we find no close aspects to the personal planets other than Venus. Nevertheless with Jupiter on the Asc we could expect 6th house issues to be more prominent.
Progession and vocation
Many of you had a look at this area for MT using the 10th house ruler.
The problem is that we don't all get to fulfil our vocations- so the 10th house is only part of the picture. It is less easy to say what the rest of teh picture is though. Sun? Ascendant ruler?
Obviously Gates was into software writing
Is this in his 10th? Well Jupiter rules the 10th and is in the 3rd of communications ( he could literally be big in communications?) but I think the Moon is at least as important here - being his chart ruler and in 10th house.
The Moon is in Mars ruled Aries and Mars is very important for mathematical logic (not to be confused with arithmetical manipulation which is the domain of Mercury) and is here in conjunction with Mercury anyway.
Further we should also consider that he now has a new vocation - as a philanthropist. This is much more descriptive of Jupiter in Pisces I woudl think.
What about MT?
Estebon's guess of Music and other similar thoughts based on the Taurus MC were totally logical. I don't know why it is not that simple - maybe the presence of Saturn in conjunction with the MC ruler and based opposite the MC restricted the opportunities to follow the true vocation and meant that another part of the chart had to be accessed by the native.
PallasAthene did get it right after I hinted at a different approach with
writer or journalist specialising in travel.. possibly foreign affairs, like a foreign correspondent. With mars, war zones?? Or adventure travel.
Not adventure travel, but he has definitely been a journalist /foreign correspondent.
So I am presuming that in the absence of the ability to embrace Venus, the chart ruler or Sun ( in this case they are the same) came into play. (there are other possibilities re directions at the point of starting career etc). So with the Sun in 3rd MT is a journalist. Whilst he isn't necessarily a war corespondent - he has worked on some war related assignments.
Enough of the differences though. Interestingly most of MT's career has been spent with a global communications company with also has a significant technology division. So there is actually quite an overlap in the nature of their work.
It is even amusing that in Gates last few years as CEO of Microsoft he focussed on security and MT is currently a security correspondent.
( I guess that would be the Scorpio influence
)
Sphere of influence
I asked if anyone could compare these, but it was hard to explain what I meant without giving away the information. I meant is this a person confined to their local neighbourhood or is their reach broader. We can now see that as an international jouranlist it may be wide. In fact he has lived in Asia, Middle east and more than one country in Africa. Many of the countries in fact that Gates foundations now seek to help. And in fact MT's presence there has been physical rather than financial.
So in terms of where they have had influence they are similar. What, of course, is missing with MT is the level of eminence that Gates has.....
Wealth
....And the money! MT is a typical comfortable professional but not at all 'wealthy' by western standards. Indeed I rented a room from him in order that he could earn a little extra cash for various reasons. If we go with the 2nd house for this , we see Mercury conjoining Mars and opposing the Moon - money comes and goes perhaps? Enough to expplain his normal situation. Gates, on the other hand, has the Sun in the 5th ruling his 2nd, and thus the influence of Jupiter in Leo to benefit from. Still, so do many people - we should be looking to something more for the fabulous wealth. I can't see this- must be a part, or house cusp aspect that I can't see.
relationships and children
Although their Ascendants, and thus the sign of 7th house differ the 7th house ruler in both case is Saturn. Which is obviously in both cases in conjucntion with Venus.
Gates got married quite late 1994 (so he was 38).
He then conventionally had three children :
? Daughter Born in 1996.
? Son Born in 1999.
? Daughter Born in 2002
MT's situation is more complicated ( maybe the subtle difference of Aquarius rather than Capricorn). The suggestion that he would have conventional relationship history is not bourne out.
He married even later. ( a tick for Pallas for getting this)
But....
He and his ex girlfriend had a daughter late 1998
They married Dec 2001, ( mainly for convenience of daughter I think)
But he met his future wife soon after and they had a son in 2007
and he married 2nd wife in June 2008 and a further son was born in
Oct 2009. Both his wives are African. The second is much (20 years) younger - which presumably is one of the options for Saturn and Venus together. She's now a stay at home wife but wasn't at first -she's strong but not controlling as someone suggested ( at least I don't see that!!). She's also very pretty/striking.
But comparing his situation with Gates doesn't really explain why Gates is married to someone nearer his own age....Still compared to the rest of the population there is are some similar themes.
Hope that gives enough feedback on MT . If not ask, though I don't know everything and wouldn't post anything too personal about him.