Vrishchikam, or Vrischikam Masam, is the fourth month in traditional Malayalam calendar and is highly auspicious month for Ayyappa Devotees. The 41-day Sabarimala Vratham starts on Vrischikam 1 which is popularly known as Mandala Kalam. The
remains open continuously for 41 days starting from Vrishchikam month. In 2012, Vrischikam month is from November 16 to December 15. As per Malayalam Calendar this is Kolla Varsham 1188. Sabarimala Ayyappa Temple
Some of the other important auspicious days in the month include Triprayar Ekadasi, Guruvayoor Ekadasi and Trikarthika. Vrischikam 1 is known as Mandala Kala Arabham or beginning of the Sabarimala season.
The month is mainly noted for the Sabarimala Mandala Kalam and the inflow of millions of Ayyappa devotees to the hill shrine.
The corresponding month in Tamil Calendar is Kartik or Karthigai.