The Rising Sign as the name suggest is defined in astrology as the constellation emerging at east on the horizon at the moment of birth. According to astrology the ascendant is very important in the characterization of an individual and this explains the interest that there has always been around its calculation. In literature and on the internet there is a lot of material about the ascendant, as a starting point you can look at wikipedia:
If you are not interested to the computation way of ascendant but you only want to know yours, you can do it here: Calculate Ascendant!
Often can arise the curiosity to know how to calculate the ascendant, looking on the internet there are several sites that explain how to do it but for one reason or another I have not found any site that explains it in full details and so I decided to write this little tutorial using same case explained step by step.
The purpose of ascendant calculation it's to find the 'Sidereal Time' of the own birth, the sidereal time or 'stars's time' is defined as the time the earth needs to make one complete rotation around the stars and so it's useful to determine where are the stars in a given time, so knowing this figure at the time of the birth of a person it's possible 'to see' which are the rising costellation at east. For further information about sideral time you can look at:
We can start doing the 'shopping list', in other words look at which are the data we need to cumpute the ascendant calculation, do not be afraid because we will see together how to find most of the necessary informations:
1) Exact time of birth
2) There was summer time?
3) Latitude and longitude of the place of birth
4) The Time Zone
5) The tables with the constellations positions or 'houses table'
Ok! Let's start with an analysis of those data:
1) the exact time of birth is crucial for a correct calculation of ascendandt, the best way to know would be to ask the parents the exact time of birth but this is not always possible, so we can use the one on birth certificate but often it is not completely accurate because it refers to the time written by the doctor and it can be rounded... but we be satisfied
2) the information about summer time must be considered because it moves the time of one hour and you can undestand that this is essential to calculate the ascendant... for my site I build an archive of all summer time for the past years but each country has its history so I had to delegate to you to find this information on internet if you are not birth in Italy... I'm sorry
3) the latitude and longitude of a place are the coordinates to locate its position on the Earth's sphere, I think that the best way to understand these two quantities is to observe this picture:
we need to know latitude and longitude for our calculation because the appearance of the sky changes moving from one point to another and from one hemisphere of the globe to the opposite.
Today know the latitude and longitude of a place is much easier than in the past ... and we have several options:
-use gps antennas, the ones used for navigation systems ... often the navigation software has the ability to display latitude and longitude of the current position
a small window with the valuable information of latitude and longitude will appear.
-use sites that use google maps and automate the research for latitude and longitude as example the excellent:
-use data available on-line. For my site I have gathered the full details of all the Italian country and the coordinates of the major city in the world ... excellent starting points if you decide to follow this way are these sites:
4) The tables with the astral informations which we'll used are referred to Greenwich so we need to solve the question 'what time it was in Greenwich when I was born?' We therefore need to know our timezone... very useful is the image hosted on the pages of wikipedia about time zones:
for my site I had to build a database with the timezone of the main cities of the world, even here in web fortunately there is help ... I can suggest you these links:
one last thing about latitude and longitude remember that these quantities are expressed in degrees and minutes (sixtieth of a degree) we'll re-find this information below
5) Once we have reported ideally at the Greenwich meridian at the time of our birth, we can finally see the sky on the horizon and look at the emerging constellation to the east, this is a very poetic way but it is not the most comfortable, fortunately we are in aid the tables that contain this information... in the literature there are many books devoted to this purpose but, once again, we have the internet as an alternative solution, as example on this site you can find these tables that,obviously, depend on latitude:
you can see that the tables are shown only for latitudes greater than zero and thus for the north hemisphere, if we want to calculate the ascendant for someone born in the sud hemisphere it's enough to consider the table associated with the latitude without the minus sign and the reverse the results.
For my site, of course, I had to store all those informations.
Now that we know something more about ascendant we can move on to real calculation... without wasting time let's start with an example step by step and let's analyze the details of the calculation.