So, lets start with 1st of our planet through signs post. A thing to remember here is that these posts are strictly meant for the particular planet position. Like, today we are looking at Sun in Aries, so the description given here may change for you if your Sun is although in the sign of Aries but with conjunction with or aspected by other planets.

So, lets see what Sun can do in the sign of Aries. 1st lets see what these 2 things represent -

Sun represents King, Government, Father, Authority, Career, Top Positions, Ego, Self Esteem etc.

Aries is the sign of our individuality, our aggression, our actions, our competitive ability etc. Aries is ruled by Mars and it is consisted of 2 and half Nakshatras named Ashwini, Bharani and Krittika.

1st of all Sun is exalted in Aries, which means Sun is at its highest peak in the sign of Aries or at the most powerful state. But that highest peak is at 10 degrees of Aries. So, if someone is born with Sun at 10 degrees of Aries, he will get the best results of Sun (best example - Sachin Tendulkar). Sun is powerful within 5-15 degrees of Aries. In other degrees, Sun is not exalted but still in its sign of exaltation, so still powerful but not as powerful as at 10 degrees.

So, why Sun is exalted in Aries? Sun is King, Authority, Government and in the sign of Aries, Sun gets an opportunity to reach the peak of authority through individual efforts and hard work. That's why, Sun feels great here as everyone treats him like a King. 1st major impact of Sun in Aries is that this person's father not only be in position of great authority but father will also instill the best of the virtues in the person. The person will be very confident and eager to take the lead roles. He will always be leading others, as that makes him gain confidence. These people desire to be at the top position in their choice of field. They should never satisfied with mediocre success as they are meant for the top positions. As Sun represents Government, these people get benefits from Government. So, all in all, one of the greatest position to have in any horoscope. The only care these people should take is not to become too much authoritative about themselves or their achievements.

Now there are many people who are born with Sun in Aries, as Sun is in Aries for about one month (14th April to 14th May) every year, but all of them don't reach up to the top position of their field? So, where does it make a difference?

This is where the degrees, nakshatras come in to consideration. As I told, Sun will be most powerful when it is within 5-15 degree. Then, when it is in Ashwini Nakshatra, the results of Sun will be impacted by Ketu's position in horoscope as Ketu is lord of Ashwini. If it is in Bharani Nakshatra, then results of Sun will be impacted by Venus' position in horoscope as Venus is lord of Bharani. Similarly, If it is in Krittika Nakshatra, then results of Sun will be impacted by Sun's own position in horoscope as Sun is lord of Krittika.

Also, it is very important to see the condition of the lord of sign when we are seeing the results of planets through sign. So, Sun is exalted in Aries, Great!!!!! But what if Aries' lord Mars is debilitated in the sign of Cancer?  So, it is important to see the condition of the lord of a sign to judge the result of any planet in that sign. Like, in this case, to know the true results of Sun in Aries, it is very important that we must look at the condition of Mars in horoscope.

Like this, Sun's results may differ for individual though from outside it looks like same Sun in Aries.