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 (known colloquially as the "Dog Star"), which
Hellenistic astrology connected with
heat,
drought
A drought is a period of drier-than-normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, ...
, sudden
thunderstorms,
lethargy,
fever
Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with Human body temperature, body temperature exceeding the normal range caused by an increase in the body's temperature Human body temperature#Fever, s ...
,
mad dogs, and bad
luck. They are now taken to be the hottest, most uncomfortable part of summer in the
Northern Hemisphere
The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar ...
.
Etymology

The English name is a
calque
In linguistics, a calque () or loan translation is a word or phrase borrowed from another language by literal word-for-word or root-for-root translation. When used as a verb, "to calque" means to borrow a word or phrase from another language ...
of the
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
(), itself a
calque
In linguistics, a calque () or loan translation is a word or phrase borrowed from another language by literal word-for-word or root-for-root translation. When used as a verb, "to calque" means to borrow a word or phrase from another language ...
of the
ancient Greek
Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...
().
[.] The Greeks knew the star α Canis Majoris by several names, including
Sirius "Scorcher" (, ''Seírios''), Sothis (, ''Sôthis'', a transcription of
Egyptian ''
Spdt''), and the Dog Star (, ''Kúōn'').
[.] The last name reflects the way Sirius follows the
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The first constellati ...
Orion into the night sky.
History
Sirius is by far the
brightest proper star in the
night sky
The night sky is the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon.
Natural light sources in a night sky include moonlig ...
, which caused
ancient astronomers to take note of it around the world. In
Egypt
Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northe ...
, its
return to the night sky became known as a precursor to the
annual flooding of the
Nile
The Nile (also known as the Nile River or River Nile) is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa. It has historically been considered the List of river sy ...
and was worshipped as the goddess
Sopdet. In
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
, it became known as the precursor of the unpleasantly hot phase of the summer.
Greek poets even recorded the belief that the return of the bright star was responsible for bringing heat and fever with it; it was also associated with sudden
thunderstorms. In
Homer
Homer (; , ; possibly born ) was an Ancient Greece, Ancient Greek poet who is credited as the author of the ''Iliad'' and the ''Odyssey'', two epic poems that are foundational works of ancient Greek literature. Despite doubts about his autho ...
's ''
Iliad
The ''Iliad'' (; , ; ) is one of two major Ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the ''Odyssey'', the poem is divided into 24 books and ...
'', probably composed in the but representing an earlier tradition,
Achilles
In Greek mythology, Achilles ( ) or Achilleus () was a hero of the Trojan War who was known as being the greatest of all the Greek warriors. The central character in Homer's ''Iliad'', he was the son of the Nereids, Nereid Thetis and Peleus, ...
's approach toward
Troy
Troy (/; ; ) or Ilion (; ) was an ancient city located in present-day Hisarlik, Turkey. It is best known as the setting for the Greek mythology, Greek myth of the Trojan War. The archaeological site is open to the public as a tourist destina ...
, where he will slay
Hector, is illustrated through an extended metaphor about the baleful effects attending the return of
Sirius:
The rising of Sirius during this period has been calculated as 19 July (
Julian).
[.] Writing about the same time,
Hesiod considered the worst and hottest part of the summer to be the days ''before'' Sirius returned to the night sky. During this period, Sirius was invisible from the earth but it was apparently understood to still be in the sky, augmenting the power of the sun:

This effect of the combination of Sirius' light with the Sun's was understood to have an effect on plants, animals, and women, as well as men:
About a century later,
Alcaeus repeated the theme, advising his listeners to "steep your lungs in wine" before the arrival of the star since "women are at their foulest but men are weak since they are parched in head and knees". In the 3rd century,
Aratus' ''Phenomena'' describes the time as Sirius blighting the bark of trees with its heat during the time it rises and sets with the sun.
The
Kean priests of
Zeus
Zeus (, ) is the chief deity of the List of Greek deities, Greek pantheon. He is a sky father, sky and thunder god in ancient Greek religion and Greek mythology, mythology, who rules as king of the gods on Mount Olympus.
Zeus is the child ...
as Rainmaker and Lord of Moisture observed annual sacrifices before the rise of Sirius to prevent scorching drought.
[.] This practice was credited to the culture hero
Aristaeus.
[ ]Aristotle
Aristotle (; 384–322 BC) was an Ancient Greek philosophy, Ancient Greek philosopher and polymath. His writings cover a broad range of subjects spanning the natural sciences, philosophy, linguistics, economics, politics, psychology, a ...
mentions the proverbial heat of the dog days as part of his argument against an early formulation of evolution
Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...
in his ''Physics
Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...
''.
The Romans continued to blame Sirius for the heat of the season and attendant lethargy and diseases. In his ''Georgics
The ''Georgics'' ( ; ) is a poem by Latin poet Virgil, likely published in 29 BCE. As the name suggests (from the Greek language, Greek word , ''geōrgiká'', i.e. "agricultural hings) the subject of the poem is agriculture; but far from bei ...
'', Vergil notes vintners' efforts to protect their work during the time "when the Dog-star cleaves the thirsty Ground". Seneca's Oedipus complains of "the scorching dog-star's fires". Pliny's '' Natural History'' notes an increase in attacks by dogs during July and August, and advises feeding them chicken manure to curb the tendency. In the early 20th century, historians still noted the "discouraging heat" and "oppression" of the dog days of the Roman summer.
The period has long featured in western medicine. The 1564 English ''Hope of Health'' counseled that purging ( bloodletting and induced vomiting) should be avoided during the "Dogge daies" of summer because "the Sunne is in Leo" and "then is nature burnt vp & made weake". The 1729 British ''Husbandman's Practice'' claimed that "The Heat of the Sun is so violent that Men's bodies at Midnight sweat as at Midday: and if they be hurt, they be more sick than at any other time, yea very near Dead". It therefore advised men to "abstain all this time from women" and to "take heed of feeding violently". In the 1813 ''Clavis Calendria'', the dog days are a time wherein "the Sea boiled, the Wine turned sour, Dogs grew mad, Quinto raged with anger, and all other creatures became languid; causing to man, among other diseases, burning fevers, hysterics, and phrensies".
Even after astrology
Astrology is a range of Divination, divinatory practices, recognized as pseudoscientific since the 18th century, that propose that information about human affairs and terrestrial events may be discerned by studying the apparent positions ...
and its influence on health and agriculture waned in importance, the "dog days" continues to be vaguely applied to the hottest days of the summer, with its attendant effects on nature and society. In North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
, it became proverb
A proverb (from ) or an adage is a simple, traditional saying that expresses a perceived truth based on common sense or experience. Proverbs are often metaphorical and are an example of formulaic speech, formulaic language. A proverbial phrase ...
ial among farmers that a dry growing season through the dog days was preferable to the trouble of a wet one:
Because "July is typically one of the quietest months of the year for stock trading", the term is sometimes used for the lethargic summer markets.
Span
Various computations of the dog days have placed their start anywhere from 3 July to 15 August and lasting for anywhere from 30 to 61 days.[ They may begin or end with the cosmical rising or heliacal rising of either Sirius in ]Canis Major
Canis Major is a constellation in the southern celestial hemisphere. In the second century, it was included in Ptolemy's 48 constellations, and is counted among the 88 modern constellations. Its name is Latin for "greater dog" in contrast to C ...
or Procyon (the "Little Dog Star") in Canis Minor and vary by latitude
In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...
, not even being visible throughout much of the Southern Hemisphere.[ Sirius observes a period of almost exactly 365¼ days between risings, keeping it largely consistent with the Julian but not the Gregorian calendar; nonetheless, its dates occur somewhat later in the year over a span of millennia.][
In antiquity, the dog days were usually reckoned from the appearance of Sirius][ around 19 July (Julian)][ to relieving rains and cool winds, although Hesiod seems to have counted the worst of summer as the days leading up to Sirius's reappearance.][
In Anglo-Saxon England, the dog days ran from various dates in mid-July to early or mid-September. Canonical "dog daies" were observed from July 7 to September 5 in the 16th-century English ]liturgies
Liturgy is the customary public ritual of worship performed by a religious group. As a religious phenomenon, liturgy represents a community, communal response to and participation in the sacred through activities reflecting praise, thanksgiving, ...
. They were removed from the prayer books at the restoration of the monarchy in 1660 and their term shortened to the time between July 19 and August 20.[.] During the British adoption of the Gregorian calendar in 1752, they were shifted from July 30 to September 7.[
Many modern sources in the ]English-speaking world
The English-speaking world comprises the 88 countries and territories in which English language, English is an official, administrative, or cultural language. In the early 2000s, between one and two billion people spoke English, making it the ...
move this still earlier, from July 3 to August 11,[ ending rather than beginning with or centering on the reappearance of Sirius to the night sky.
]
Scientific basis
Although Sirius is the brightest proper star in the night sky, it is away from Earth and has no effect whatsoever on the planet's weather or temperature. Although the star continues to return to the night sky in late summer, its position continues to gradually shift relative to the Sun and will rise in the middle of winter
Winter is the coldest and darkest season of the year in temperate and polar climates. It occurs after autumn and before spring. The tilt of Earth's axis causes seasons; winter occurs when a hemisphere is oriented away from the Sun. Dif ...
in about 10,000 years.
The effects of summer heat and rainfall patterns are real, but vary by latitude and location according to many factors. For example, London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...
, UK, is slightly farther north than Calgary
Calgary () is a major city in the Canadian province of Alberta. As of 2021, the city proper had a population of 1,306,784 and a metropolitan population of 1,481,806 making it the third-largest city and fifth-largest metropolitan area in C ...
, Canada, but has a milder climate from the presence of the sea and the warm Gulf Stream
The Gulf Stream is a warm and swift Atlantic ocean current that originates in the Gulf of Mexico and flows through the Straits of Florida and up the eastern coastline of the United States, then veers east near 36°N latitude (North Carolin ...
current. A medical institution has reported a connection between Finland
Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...
's dog days and increased risk of infection in deep surgery wounds, although that research remains unverified.
In popular culture
It is possible that Saint Roch, the legendary medieval patron saint of dogs celebrated by the Catholic Church
The Catholic Church (), also known as the Roman Catholic Church, is the List of Christian denominations by number of members, largest Christian church, with 1.27 to 1.41 billion baptized Catholics Catholic Church by country, worldwid ...
on 16 August, owes some of his legacy to the dog days. From the period of his self-proclaimed protectorate over the island, the Danish adventurer Jørgen Jørgensen is remembered in Iceland
Iceland is a Nordic countries, Nordic island country between the Atlantic Ocean, North Atlantic and Arctic Oceans, on the Mid-Atlantic Ridge between North America and Europe. It is culturally and politically linked with Europe and is the regi ...
as Jørgen the Dog-Day King ().
In western literature, apart from the Greek and Roman works mentioned above, the dog days appear in John Webster's 1613 play '' The Duchess of Malfi'', Charles Dickens
Charles John Huffam Dickens (; 7 February 1812 – 9 June 1870) was an English novelist, journalist, short story writer and Social criticism, social critic. He created some of literature's best-known fictional characters, and is regarded by ...
' 1843 novella '' A Christmas Carol'', R.H. Davis's 1903 short story "The Bar Sinister", J.M. Synge's 1909 poem "Queens", and Richard Adams's 1972 novel '' Watership Down''. They feature in the children's novels '' Tuck Everlasting'' (1973), and '' Dog Days'' (2009) from the '' Diary of a Wimpy Kid'' series.
'' Dog Days'' is also the title of a Japanese anime
is a Traditional animation, hand-drawn and computer animation, computer-generated animation originating from Japan. Outside Japan and in English, ''anime'' refers specifically to animation produced in Japan. However, , in Japan and in Ja ...
series that premiered in 2011. The story revolves around a boy named Shinku Izumi, who is summoned to an alternate world where the inhabitants have animal ears and tails.
In film, '' Dog Day Afternoon'' (1975) and ( German for "Dog Days"; 2001) evoke their oppressive seasonal settings. The 2010 videogame Kane & Lynch 2: Dog Days utilizes the term to a similar effect.
In music, there are Head of David's " Dog Day Sunrise", covered by Fear Factory in 1995; Florence and the Machine's 2009 " Dog Days Are Over";[.] and Within Temptation
Within Temptation is a Dutch symphonic metal band founded in April 1996 by vocalist Sharon den Adel and guitarist Robert Westerholt. They have been classified by critics as gothic metal and symphonic metal, although each album contains other infl ...
's 2013 "Dog Days"; as well as the album '' Dog Days'' by the US southern rock band Atlanta Rhythm Section; in the title track from Taylor Swift
Taylor Alison Swift (born December 13, 1989) is an American singer-songwriter. Known for her autobiographical songwriting, artistic versatility, and Cultural impact of Taylor Swift, cultural impact, Swift is one of the Best selling artists, w ...
's 2020 album '' Evermore'', Bon Iver, who is featured on the song, mentions "the violence of the dog days".
'' Dog Days'' is also the title of a 2012 opera by composer David T. Little and librettist Royce Vavrek, based on the short story by Judy Budnitz.
"Dog-day" promotions are also a common feature in baseball
Baseball is a bat-and-ball games, bat-and-ball sport played between two team sport, teams of nine players each, taking turns batting (baseball), batting and Fielding (baseball), fielding. The game occurs over the course of several Pitch ...
, used by American ballparks to boost ticket sales during mid-afternoon games.
See also
* Silly season
* Star lore
Notes
References
Bibliography
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* .
* , excerpted by th
University of Toronto Library
* .
* .
* , reprinted in 1914 as Vol. XLVII, Pt. 4, of the ''Harvard Classics'' series.
External links
* {{Wiktionary-inline
Canis Major
History of astrology
Roman calendar
Summer