Natal Rahu house is the sign where your Rahu was placed during birth time, and from there other houses are calculated clock-wise.
If you were born with Rahu in Libra, then your natal Rahu house is Libra (Thula Rasi) and during transit, Sun forming conjunction (in libra), sextile (aspect of 60° which are Sagittarius and Leo in this case), square (aspect of 90° which are Capricorn and Cancer here), trine (aspect of 120° which are Aquarius and Gemini here), opposition (aspect of 180° which is Aries here) are discussed in this article.
Conjunction is transiting through same sign as in birth chart, sextile is transiting 3rd or 11th house, trine is transiting 5th or 9th house, opposition is transiting 7th house from natal sign.
Transit SUN conjunct Natal Rahu : You will try to be in harmony with existing trends and social attitudes.
Good time to gain popularity, recognition and gains through display of artistic talents.
You will be highly creative.
Benefits in speculation, romance and education of kids.
Transit SUN Sextile Natal Rahu : You are mentally attuned to current day customs and beliefs.
Social activities, leadership qualities are highlighted.
You need to create balance in between old belief system and new trends.
Transit SUN Square Natal Rahu : This transit has similar results to Sextile as above.
This time, you will be able to blend traditional values with modern outlook.
People will expect you to perform at your peak.
Transit SUN Trine Natal Rahu : There will be turmoil and dilemma regarding choices to be made.
Good transit for speculations, finding new romantic relationships.
Health will improve this month.
Transit SUN Opposition Natal Rahu : Not good time for social relations and health. Financially it will be better than previous month.
Need to practice anger management and stay away from unnecessary meetings, gossips.
Headaches, Migraines can occur frequently.