Short answer
Ashtama Shani is Saturn passing through the 8th sign from your Moon sign; Ardhashtama Shani (also called Kantaka Shani) is Saturn in the 4th. As of November 2026, with Saturn in Meena, Simha Moon signs have Ashtama Shani and Dhanus has Ardhashtama Shani. Both shift when Saturn enters Mesha on 3 Jun 2027.
How ChiChakra reads this
Count your Moon sign as 1 and go forward to the sign Saturn is in. Each stretch lasts as long as Saturn stays in one sign, roughly two and a half years. Traditionally the 8th is linked with delays, sudden changes and stamina, and the 4th with home, property, comfort and peace of mind.
Who has it, and when it moves
Simha: Ashtama Shani now. It eases when Saturn enters Mesha on 3 Jun 2027, comes back while Saturn returns to Meena (21 Oct 2027 – 24 Feb 2028), then ends.
Dhanus: Ardhashtama Shani now, on the same timetable.
Next in line: from 3 Jun 2027, Saturn in Mesha gives Kanya Ashtama Shani and Makara Ardhashtama Shani, settling from 24 Feb 2028.
If it's yours: keep plans realistic, protect your energy, double-check property and paperwork, and allow extra time rather than extra worry.
Good to know
Neither is Sade Sati, though the two are often confused. A Moon sign shows the general climate; your birth chart shows how strongly Saturn lands for you, and personal readings are coming (waitlist).