Dog days Dog days The dog days or are the hot, sultry days of summer. They were historically the period following the heliacal rising of the star system Sirius, which Greek and Roman astrology connected with heat, drought, sudden thunderstorms, lethargy, fever, mad dogs, and bad luck. They are now taken to be the hottest, most uncomfortable part of summer in the Northern Hemisphere. The English name is a calque of the Latin "" (."the puppy days"), itself a calque of the Greek "kynádes hēmérai" (, "dog days"). The Greeks knew the star α Canis Majoris by several names, including Sirius (,
Sirius "Aa" ("glowing"), "Hoku-kauopae", "Kau-ano-meha" (also "Kaulanomeha"), "Standing-alone-and-sacred", "Hiki-kauelia" or "Hiki-kauilia" (the navigational name), "Hiki-kau-lono-meha" ("star of solitary Lono", the astrological name), "Kaulua" (also "Kaulua-ihai-mohai", "flower of the heavens"), "Hiki-kauelia", "Hoku-hoo-kele-waa" ("star which causes the canoe to sail", a marine navigation name), and "Kaulua-lena" ("yellow star"). The people of the Society Islands called Sirius variously "Taurua-fau-papa", "Taurua-nui-te-amo-aha", and "Taurua-e-hiti-i-tara-te-feiai". Other names for Sirius included "Palolo-mua" (Futuna), "Mere" (Mangaia), "Apura" (Manihiki), "Taku-ua" (Marquesas Islands), and "Tokiva" (Pukapuka). In the cosmology of the Tuamotus, Sirius had various names, including "Takurua-te-upuupu", "Te Kaha" ("coconut fibre"), "Te Upuupu", "Taranga", and "Vero-ma-torutoru" ("flaming and diminishing"). The