Natal Ketu house is the sign where your Ketu was placed during birth time, and from there other houses are calculated clock-wise.
If you were born with Ketu in Libra, then your natal Ketu house is Sagittarius (Dhanus Rasi) and during transit, Sun forming conjunction (in sagittarius), sextile (aspect of 60° which are Aquarius and Libra in this case), square (aspect of 90° which are Pisces and Virgo here), trine (aspect of 120° which are Aries and Leo here), opposition (aspect of 180° which is Gemini 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 Ketu : 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.
Judgement and decision making can be afflicted.
Transit SUN Sextile Natal Ketu : There will be turmoil and dilemma regarding choices to be made.
Good transit for speculations, finding new romantic relationships.
Health will improve this month.
Adventures should be avoided as they can lead to accidents.
Transit SUN Square Natal Ketu : 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 Ketu : 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 Opposition Natal Ketu : 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.