Mars, 1st century, found in the Forum of Nerva (Capitoline Museums, Rome)

Religion in ancient Rome
Marcus Aurelius (head covered) sacrificing at the Temple of Jupiter
Practices and beliefs
libation · sacrifice · votum · temples · festivals  · ludi · funerals · auspice Imperial cult · mystery religions
Priesthoods
Pontifex · Augur · Vestal · Flamen Fetial · Epulones · Arval Brethren
Deities
List of Roman deities Twelve major gods Capitoline Triad · Aventine Triad underworld gods · indigitamenta Deified emperors: Divus Julius  · Divus Augustus
Related topics
Roman mythology Glossary of ancient Roman religion Religion in ancient Greece Etruscan religion Gallo-Roman religion Decline of Hellenistic polytheism
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Mars (Latin: Mārs, adjectives Martius and Martialis) was the Roman god of war and also an agricultural guardian, a combination characteristic of early Rome.^[1] He was second in importance only to Jupiter, and he was the most prominent of the military gods worshipped by the Roman legions. His festivals were held in March, the month named for him (Latin Martius), and in October, which began and ended the season for military campaigning and farming.

Under the influence of Greek culture, Mars was identified with the Greek god Ares, whose myths were reinterpreted in Roman literature and art under the name of Mars. But the character and dignity of Mars differed in fundamental ways from that of his Greek counterpart, who is often treated with contempt and revulsion in Greek literature.^[2] Mars was a part of the Archaic Triad along with Jupiter and Quirinus, the latter of whom as a guardian of the Roman people had no Greek equivalent. Mars' altar in the Campus Martius, the area of Rome that took its name from him, was supposed to have been dedicated by Numa himself, the peace-loving semi-legendary second king of Rome. Although the center of Mars' worship was originally located outside the pomerium, or sacred boundary of Rome, Augustus brought the god into the center of Roman religion by establishing the Temple of Mars Ultor in his new forum.^[3]

Although Ares was viewed primarily as a destructive and destabilizing force, Mars represented military power as a way to secure peace, and was a father (pater) of the Roman people.^[4] In the mythic genealogy and founding myths of Rome, Mars was the father of Romulus and Remus with Rhea Silvia. His love affair with Venus symbolically reconciled the two different traditions of Rome's founding; Venus was the divine mother of the hero Aeneas, celebrated as the Trojan refugee who "founded" Rome several generations before Romulus laid out the city walls.

The importance of Mars in establishing religious and cultural identity within the Roman Empire is indicated by the vast number of inscriptions identifying him with a local deity, particularly in the Western provinces.

Birth[link]

Although Ares was the son of Zeus and Hera,^[5] Mars was the son of Juno alone. Jupiter had usurped the mother's function when he gave birth to Minerva directly from his forehead (or mind); to restore the balance, Juno sought the advice of the goddess Flora on how to do the same. Flora obtained a magic flower (Latin flos, plural flores, a masculine word) and tested it on a heifer who became fecund at once. She then plucked a flower ritually using her thumb, touched Juno's belly, and impregnated her. Juno withdrew to Thrace and the shore of Marmara for the birth.

Ovid tells this story in the Fasti, his long-form poetic work on the Roman calendar.^[6] It may explain why the Matronalia, a festival celebrated by married women in honor of Juno as a goddess of childbirth, occurred on the first day of Mars' month, which is also marked on a calendar from late antiquity as the birthday of Mars. In the earliest Roman calendar, March was the first month, and the god would have been born with the new year.^[7] Ovid is the only source for the story. He may be presenting a literary myth of his own invention, or an otherwise unknown archaic Italic tradition; either way, in choosing to include the story, he emphasizes that Mars was connected to plant life and was not alienated from female nurture.^[8]

Consort[link]

The consort of Mars was Nerio or Nerine, "Valour." She represents the vital force (vis), power (potentia) and majesty (maiestas) of Mars.^[9] Her name was regarded as Sabine in origin and is equivalent to Latin virtus, "manly virtue" (from vir, "man").^[10] In the early 3rd century BC, the comic playwright Plautus has a reference to Mars greeting Nerio, his wife.^[11] A source from late antiquity says that Mars and Nerine were celebrated together at a festival held on March 23.^[12] In the later Roman Empire, Nerine came to be identified with Minerva.^[13]

Nerio probably originates as a divine personification of Mars' power, as such abstractions in Latin are generally feminine. Her name appears with that of Mars in an archaic prayer invoking a series of abstract qualities, each paired with the name of a deity. The influence of Greek mythology and its anthropomorphic gods may have caused Roman writers to treat these pairs as "marriages."^[14]

St. Augustine disapprovingly gives Mars and the war goddess Bellona as an example of a divine couple who were also sister and brother.^[15]

Essential nature[link]

Virility as a kind of life force (vis) or virtue (virtus) is an essential characteristic of Mars.^[16] As an agricultural god, he directs his energies toward creating conditions that allow crops to grow, which may include warding off hostile forces of nature.^[17] As an embodiment of masculine aggression, he is the force that drives wars – but ideally, war that delivers a secure peace.

The priesthood of the Arval Brothers called on Mars to drive off "rust" (lues), with its double meaning of wheat fungus and the red oxides that affect metal, a threat to both iron farm implements and weaponry. In the surviving text of their hymn, the Arval Brothers invoked Mars as ferus, "savage" or "feral" like a wild animal.^[18]

Mars' potential for savagery is expressed in his obscure connections to the wild woodlands, and he may even have originated as a god of the wild, beyond the boundaries set by humans, and thus a force to be propitiated.^[19] In his book on farming, Cato invokes Mars Silvanus for a ritual to be carried out in silva, in the woods, an uncultivated place that if not held within bounds can threaten to overtake the fields needed for crops.^[20] Mars' character as an agricultural god may derive solely from his role as a defender and protector,^[21] or may be inseparable from his warrior nature,^[22] as the leaping of his armed priests the Salii was meant to quicken the growth of crops.^[23]

Sacred animals[link]

She-wolf and twins from an altar to Venus and Mars

Black Woodpecker, perhaps the picus Martius of the Romans

The two wild animals most sacred to Mars were the woodpecker and the wolf, which in the natural lore of the Romans were said always to inhabit the same foothills and woodlands.^[24]

Plutarch notes that the woodpecker (picus) is sacred to Mars because "it is a courageous and spirited bird and has a beak so strong that it can overturn oaks by pecking them until it has reached the inmost part of the tree."^[25] As the beak of the picus Martius contained the god's power to ward off harm, it was carried as a magic charm to prevent bee stings and leech bites.^[26] The bird of Mars also guarded a woodland herb (paeonia) used for treatment of the digestive or female reproductive systems; those who sought to harvest it were advised to do so by night, lest the woodpecker jab out their eyes.^[27] The picus Martius seems to have been a particular species, but authorities differ on which one: perhaps Picus viridis^[28] or Dryocopus martius.^[29]

The woodpecker was revered by the Latin peoples, who abstained from eating its flesh.^[30] It was one of the most important birds in Roman and Italic augury, the practice of reading the will of the gods through watching the sky for signs.^[31] The mythological figure named Picus had powers of augury that he retained when he was transformed into a woodpecker; in one tradition, Picus was the son of Mars.^[32] The Umbrian cognate peiqu also means "woodpecker," and the Italic Picenes were supposed to have derived their name from the picus who served as their guide animal during a ritual migration undertaken as a rite of Mars.^[33] In the territory of the Aequi, another Italic people, Mars had an oracle of great antiquity where the prophecies were supposed to be spoken by a woodpecker perched on a wooden column.^[34]

Mars' association with the wolf is familiar from what may be the most famous of Roman myths, the story of how a she-wolf (lupa) suckled his infant sons when they were exposed by order of their human uncle, who feared that they would take back the kingship he had usurped.^[35] A lesser-known part of the story is that the woodpecker also brought nourishment to the twins.^[36]

The wolf appears elsewhere in Roman art and literature in masculine form as the animal of Mars. A statue group that stood along the Appian Way showed Mars in the company of wolves.^[37] At the Battle of Sentinum in 295 BC, the appearance of the wolf of Mars (Martius lupus) was a sign that Roman victory was to come.^[38]

In Roman Gaul, the goose was associated with the Celtic forms of Mars, and archaeologists have found geese buried alongside warriors in graves. The goose was considered a bellicose animal because it is easily provoked to aggression.^[39]

The procession of the suovetaurilia

Sacrificial animals[link]

Ancient Greek and Roman religion distinguished between animals that were sacred to a deity and those that were prescribed as the correct sacrificial offerings for the god. Wild animals might be viewed as already belonging to the god to whom they were sacred, or at least not owned by human beings and therefore not theirs to give. Since sacrificial meat was eaten at a banquet after the gods received their portion – mainly the entrails (exta) — it follows that the animals sacrificed were most often, though not always, domestic animals normally part of the Roman diet.^[40] Most gods received castrated male animals as sacrifices, and the goddesses female victims; Mars, however, was one of the few male deities who regularly received intact males.^[41] Mars did receive oxen under a few of his cult titles (see Mars Grabovius below), but the usual offering was the bull, singly, in multiples, or in combination with other animals.

The two most distinctive animal sacrifices made to Mars were the suovetaurilia, a triple offering of a pig (sus), ram (ovis) and bull (taurus),^[42] and the October Horse, the only horse sacrifice known to have been carried out in ancient Rome and a rare instance of a victim the Romans considered inedible.^[43]

Iconography[link]

Nude statue of Mars^[44] in a garden setting, as depicted on a wall painting from Pompeii

In Roman art, Mars is depicted as either bearded and mature or young and clean-shaven. Even nude or seminude, he often wears a helmet or carries a spear as emblems of his warrior nature.

On the Augustan Altar of Peace (Ara Pacis), built in the last years of the 1st century BC, Mars is a mature man with a "handsome, classicizing" face, and a short curly beard and moustache. His helmet is a plumed neo-Attic-type. He wears a military cloak (paludamentum) and a cuirass ornamented with a gorgoneion. Although the relief is somewhat damaged at this spot, he appears to hold a spear garlanded in laurel, symbolizing a peace that is won by military victory. (Compare the 1st-century statue of Mars found in the Forum of Nerva, pictured above.) In this guise, Mars is presented as the dignified ancestor of the Roman people. The panel of the Ara Pacis on which he appears would have faced the Campus Martius, reminding viewers that Mars was the god whose altar Numa established there, that is, the god of Rome's oldest civic and military institutions.^[45]

Particularly in works of art influenced by the Greek tradition, Mars may be portrayed in a manner that resembles Ares, youthful, beardless, and often nude.^[46]

The spear of Mars[link]

The spear is the instrument of Mars in the same way that Jupiter wields the lightning bolt, Neptune the trident, and Saturn the scythe or sickle.^[47] A relic or fetish called the spear of Mars^[48] was kept in a sacrarium at the Regia, the former residence of the Kings of Rome.^[49] The spear was said at times to move, tremble or vibrate at impending danger to the state, as was reported to occur before the assassination of Julius Caesar.^[50] When Mars is pictured as a peace-bringer, his spear is wreathed with laurel or other vegetation, as on the Ara Pacis or a coin of Aemilianus.^[51]

Festivals[link]

Denarius, issued 88 BC, depicting the helmeted head of Mars, with Victory driving a two-horse chariot (biga) on the reverse

The festivals of Mars cluster in his namesake month of March (Latin Martius), with a few observances in October, the beginning and end of the season for military campaigning and agriculture. Festivals with horse racing took place in the Campus Martius, "Field of Mars."

• Equirria, February 27, involving chariot or horse races;
• his dies natalis ("birth day") on March 1, a feria also sacred to his mother Juno (see "Birth" above);^[52]
• a second Equirria, March 14, again with chariot races;
• an Agonalia or Agonium Martiale, an obscure type of observance held at other times for various deities, with that of Mars on March 17;
• Tubilustrium, a purification of the deploying army March 23;
• the ritual of the October Horse, with a chariot race and Rome's only known horse sacrifice October 15;
• Armilustrium ("purification of arms") October 19.

Mars was also honored by chariot races at the Robigalia and Consualia, though these festivals are not primarily dedicated to him. From 217 BC onward, Mars was among the gods honored at the lectisternium, a banquet given for deities who were present as images.

Priesthoods[link]

The high priest of Mars in Roman public religion was the Flamen Martialis, who was one of the three major priests in the fifteen-member college of flamens. Mars was also served by the Salii, a twelve-member priesthood of patrician youths who dressed as archaic warriors and danced in procession around the city in March. Both priesthoods extend to the earliest periods of Roman history.

Name and epithets[link]

The so-called Mars of Todi (Etruscan bronze, late 5th–early 4th century BC), probably a warrior with hand extended to make an offering^[53]

The word Mārs (genitive Mārtis),^[54] which in Old Latin and poetic usage also appears as Māvors (Māvortis),^[55] is cognate with Oscan Māmers (Māmertos).^[56] The Old Latin form was believed to derive from an Italic *Māworts, however this name is from Etruscan Maris, originally a god of vegetation and not of war. Adjective forms are martius and martialis, from which derive English "martial" (as in "martial arts" or "martial law") and personal names such as "Martin". The Campus Martius bore his name.

Mars also gave his name to the third month in the Roman calendar, Martius, from which English "March" derives. In the most ancient Roman calendar, Martius was the first month. In many languages Tuesday^[57] is named for the planet Mars or the God of War (see "Days of the Week Planetary table"), in Latin Martis Dies (Mars' Day), surviving in Romance languages as Martes (Spanish), Mardi (French), Martedi (Italian), Marţi (Romanian), and Dimarts (Catalan), compare An Mháirt (Irish/Gaelic).

In Roman religion[link]

Mars received cult within the traditional religion of Rome under several specific manifestations.

Mars Gradivus[link]

Gradivus was one of the gods by whom a general or soldiers might swear an oath to be valorous in battle.^[58] His temple outside the Porta Capena was where armies gathered. The archaic priesthood of Mars Gradivus was the Salii, the "leaping priests" who danced ritually in armor as a prelude to war.^[59] His cult title is most often taken to mean "the Strider" or "the Marching God," from gradus, "step, march."^[60]

The poet Statius addresses him as "the most implacable of the gods,"^[61] but Valerius Maximus concludes his history by invoking Mars Gradivus as "author and support of the name 'Roman'":^[62] Gradivus is asked – along with Capitoline Jupiter and Vesta, as the keeper of Rome's perpetual flame – to "guard, preserve, and protect" the state, the peace, and the princeps (the emperor Tiberius at the time).^[63]

A source from late antiquity says that the wife of Gradivus was Nereia, the daughter of Nereus, and that he loved her passionately^[64] (compare Nerio above).

Mars Quirinus[link]

Mars celebrated as peace-bringer on a Roman coin issued by Aemilianus

Mars Quirinus was the protector of the Quirites ("citizens" or "civilians") as divided into curiae (citizen assemblies), whose oaths were required to make a treaty.^[65] As a guarantor of treaties, Mars Quirinus is thus a god of peace: "When he rampages, Mars is called Gradivus, but when he's at peace Quirinus."^[66]

The deified Romulus was identified with Mars Quirinus. In the Archaic Triad of Jupiter, Mars, and Quirinus, however, Mars and Quirinus were two separate deities, though not perhaps in origin. Each of the three had his own flamen (specialized priest), but the functions of the Flamen Martialis and Flamen Quirinalis are hard to distinguish.^[67]

Mars Grabovius[link]

Mars is invoked as Grabovius in the Iguvine Tables, bronze tablets written in Umbrian that record ritual protocols for carrying out public ceremonies on behalf of the city and community of Iguvium. The same title is given to Jupiter and to the Umbrian deity Vofionus. This triad has been compared to the Archaic Triad, with Vofionus equivalent to Quirinus.^[68] Tables I and VI describe a complex ritual that took place at the three gates of the city. After the auspices were taken, two groups of three victims were sacrificed at each gate. Mars Grabovius received three oxen.^[69]

Mars Pater[link]

"Father Mars" or "Mars the Father" is the form in which the god is invoked in the agricultural prayer of Cato,^[70] and he appears with this title in several other literary texts and inscriptions.^[71] Mars Pater is among the several gods invoked in the ritual of devotio, by means of which a general sacrificed himself and the lives of the enemy to secure a Roman victory.^[72]

Father Mars is the regular recipient of the suovetaurilia, the sacrifice of a pig (sus), ram (ovis) and bull (taurus), or often a bull alone.^[73] To Mars Pater other epithets were sometimes appended, such as Mars Pater Victor ("Father Mars the Victorious"),^[74] to whom the Roman army sacrificed a bull on March 1.^[75]

Although pater and mater were fairly common as honorifics for a deity,^[76] any special claim for Mars as father of the Roman people lies in the mythic geneaology that makes him the divine father of Romulus and Remus.^[77]

Mars Silvanus[link]

In the section of his farming book that offers recipes and medical preparations, Cato describes a votum to promote the health of cattle:

Make an offering to Mars Silvanus in the forest (in silva) during the daytime for each head of cattle: 3 pounds of meal, 4½ pounds of bacon, 4½ pounds of meat, and 3 pints of wine. You may place the viands in one vessel, and the wine likewise in one vessel. Either a slave or a free man may make this offering. After the ceremony is over, consume the offering on the spot at once. A woman may not take part in this offering or see how it is performed. You may vow the vow every year if you wish.^[78]

That Mars Silvanus is a single entity has been doubted. Invocations of deities are often list-like, without connecting words, and the phrase should perhaps be understood as "Mars and Silvanus".^[79] Women were explicitly excluded from some cult practices of Silvanus, but not necessarily of Mars.^[80] William Warde Fowler, however, thought that the wild god of the wood Silvanus may have been "an emanation or offshoot" of Mars.^[81]

Mars Ultor[link]

Augustus created the cult of "Mars the Avenger" to mark two occasions: his defeat of the assassins of Caesar at Philippi in 42 BC, and the negotiated return of the Roman battle standards that had been lost to the Parthians at the Battle of Carrhae in 53 BC. The god is depicted wearing a cuirass and helmet and standing in a "martial pose," leaning on a lance he holds in his right hand. He holds a shield in his left hand.^[82]

A great temple of Mars Ultor was dedicated in the center of the Forum of Augustus in 2 BC, giving the god a new place of honor in the heart of the city when he had formerly been most associated with the Campus Martius outside the pomerium (sacred boundary).^[83] Some rituals previously conducted within the cult of the Capitoline Jupiter were transferred to the new Temple of Mars Ultor,^[84] which became the point of departure for magistrates as they left for military campaigns abroad.^[85]

On various Imperial holidays, Mars Ultor was the first god to receive a sacrifice, followed by the Genius of the emperor.^[86] An inscription from the 2nd century records continued devotion to Mars Ultor, with a vow to offer him a bull with gilded horns.^[87]

Mars Augustus[link]

Augustus was appended far and wide, "on monuments great and small,"^[88] to the name of gods or goddesses (as Augusta), including Mars. The title may have been an honorific for the deity for the same reasons that it became the title for the former Octavian, but while it honored the deity as the source of the emperor's power and legitimacy, it may also have allowed the viewer to infer that the deity and the emperor were one.^[89]

In Roman Spain (Hispania), many of the statues and dedications to Mars Augustus were presented by members of the priesthood called the Augustales.^[90] These vows (vota) were usually fulfilled within a sanctuary that functioned as a center for Imperial cult, or in a temple or precinct (templum) consecrated specifically to Mars.^[91] As with other deities invoked as Augustus/-a, altars to Mars Augustus might be set up to further the wellbeing (salus) of the emperor,^[92] but an inscription in the Alps records the gratitude of a slave who dedicated a statue to Mars Augustus for restoring his own health.^[93]

Mars Augustus appears in inscriptions at such locations as Baetica, Saguntum,^[94] and Emerita (Lusitania) in Roman Spain;^[95] Lepcis Magna (with a date of 6–7 AD) in present-day Libya;^[96] and Sarmizegetusa in the province of Dacia.^[97]

Provincial epithets[link]

In addition to his cult titles at Rome, Mars appears in a large number of inscriptions in the provinces of the Roman Empire, and more rarely in literary texts, identified with a local deity by means of an epithet. Mars appears with great frequency in Gaul among the Continental Celts, as well as in Roman Spain and Britain. In Celtic settings, he is often invoked as a healer.^[98] The inscriptions indicate that Mars' ability to dispel the enemy on the battlefield was transferred to the sick person's struggle against illness; healing is expressed in terms of warding off and rescue.^[99]

• Mars Alator, a fusion of Mars with the Celtic deity Alator (possibly meaning "Huntsman" or "Cherisher"), known from an inscription found in England, on an altar at South Shields and a silver-gilt votive plaque at Barkway, Hertfordshire.^[100][101]
• Mars Albiorix, a fusion of Mars with the ancient Celtic deity Toutatis, using the epithet Albiorix ("King of the World"). Mars Albiorix was worshiped as protector of the Albici (or Albioeci) tribe of southern France, and was regarded as a mountain god. Another epithet of Toutatis, Caturix ("King of Combat"), was used in the combination Mars Caturix, which was worshipped in Gaul, possibly as the tribal god of the Caturiges.^[102]

"Mars Balearicus"

• "Mars Balearicus", a name used in modern scholarship for small bronze warrior figures from Mallorca (one of the Balearic Islands) and interpreted as representing the local Mars cult.^[103] These have been found within talayotic sanctuaries with extensive evidence of burnt offerings. "Mars" is fashioned as a lean, athletic nude lifting a lance and wearing a helmet, often conical; the genitals are perhaps semi-erect. Other bronzes at the sites represent the heads or horns of bulls, but the bones in the ash layers indicate that sheep, goats, and pigs were the sacrificial victims. Bronze horse-hooves were found in one sanctuary, and an imported statue of Imhotep, the legendary Egyptian physician, in another. The sacred precincts, which were still in active use when the Roman occupation began in 123 BC, may have been astronomically oriented toward the rising or setting of the constellation Centaurus.^[104]
• Mars Barrex, from Barrex or Barrecis (probably meaning "Supreme One"), a Celtic god known only from a dedicatory inscription found at Carlisle, England.^[101]
• Mars Belatucadrus, an epithet found in five inscriptions in the area of Hadrian's Wall in England, which equates the Celtic deity Belatu-Cadros with Mars.
• Mars Braciaca, known from a single inscription at Bakewell, England.^[101] The Celtic epithet may refer to malt or beer, though intoxication in Greco-Roman religion is associated with Dionysus.^[105] A reference in Pliny^[106] suggests a connection to Mars' agricultural function, with the Gaulish word bracis referring to a type of wheat; a medieval Latin gloss says it was used to make beer.^[107]
• Mars Camulos, from the Celtic war god Camulus.
• Mars Capriociegus, from an Celtic god who was linked to Mars. He is invoked in two inscriptions in the Pontevedra region of north-west Spain.
• Mars Cocidius. The Celtic hunter god Cocidius was equated with both Mars and Silvanus.^[108] He is referenced around north-west Cumbria and Hadrian's Wall, and was chiefly a war god only in instances where he was equated with Mars.
• Mars Condatis, from the Celtic god of the confluence of rivers, Condatis. Mars Condatis, who oversaw water and healing, is known from inscriptions near Hadrian's Wall, at Piercebridge, Bowes and Chester-le-Street.^[101][109]
• Mars Corotiacus. A local British version of Mars from Martlesham in Suffolk. He appears on a bronze statuette as a cavalryman, armed and riding a horse which tramples a prostrate enemy beneath its hooves.^[102]
• Mars Lenus. Mars Lenus, sometimes founds as Lenus Mars, had a major healing cult at the capital of the Treveri (present-day Trier). Among the votives are images of children offering doves.^[110] His consort was Ancamna.
• Mars Loucetius. The Celtic god Loucetios, Latinized as -ius, appears in nine inscriptions in present-day Germany and France and one in Britain, and in three as Leucetius. The Gaulish and Brythonic theonyms likely derive from Proto-Celtic *louk(k)et-, "bright, shining, flashing," hence also "lightning,"^[111] alluding to either a Celtic commonplace metaphor between battles and thunderstorms (Old Irish torannchless, the "thunder feat"), or the aura of a divinized hero (the lúan of Cú Chulainn). The name is given as an epithet of Mars. The consort of Mars Loucetius is Nemetona, whose name may be understood as pertaining either to "sacred privilege" or to the sacred grove (nemeton),^[112] and who is also identified with the goddess Victory. At the Romano-British site in Bath, a dedication to Mars Loucetius as part of this divine couple was made by a pilgrim from the continental Treveri of Gallia Belgica, who sought healing.^[113]
• Mars Mullo. The Celtic god Mullo ("mule") was invoked with Mars in northwest Gaul.^[114]
• Mars Neto. A fusion of Mars and the Iberian god Neto/Neito, which may be derived from the celtic Neit.
• Mars Nodens. A fusion of Mars with the Celtic god Nodens.
• Mars Ocelus. A fusion of Mars with the Celtic god Ocelus.
• Mars Olloudius. A fusion of Mars with the Celtic god Olloudius.
• Mars Rigisamus. Mars was given this title (which means 'Greatest King' or 'King of Kings') at West Coker in Somerset, where a bronze figurine and inscribed plaque dedicated to the god were found in a field, along with the remains of a building, perhaps a shrine. The figurine depicts a standing naked male figure with a close-fitting helmet; his right hand may have once held a weapon, and he probably originally also had a shield (both are now lost). The same epithet for a god is recorded from Bourges in Gaul. The use of this epithet implies that Mars had an extremely high status, over and above his warrior function.

A bronze Mars from Gaul

• Mars Rigonemetis ("King of the Sacred Grove"). A dedication to Rigonemetis and the numen (spirit) of the Emperor inscribed on a stone was discovered at Nettleham (Lincolnshire) in 1961. Rigonemetis is only known from this site, and it seems he may have been a god belonging to the tribe of the Corieltauvi.^[102]
• Mars Segomo. "Mars the Victorious" appears among the Celtic Sequani.^[115]
• Mars Smertrius. At a site within the territory of the Treveri, Ancamna was the consort of Mars Smertrius.^[116]
• Mars Teutates. A fusion of Mars with the Celtic god Teutates (Toutatis).
• Mars Thinesus. A form of Mars invoked at Housesteads Roman Fort at Hadrian's Wall, where his name is linked with two goddesses called the Alaisiagae. Anne Ross associated Thinesus with a sculpture, also from the fort, which shows a god flanked by goddesses and accompanied by a goose – a frequent companion of war gods.^[102]
• Mars Visucius. A fusion of Mars with the Celtic god Visucius.
• Mars Vorocius. A Celtic healer-god invoked at the curative spring shrine at Vichy (Allier) as a curer of eye afflictions. On images, the god is depicted as a Celtic warrior.^[102]

See also[link]

Wikimedia Commons has media related to: Mars (god)

• Ares
• Mars, the planet
• Nergal, the Babylonian god associated with the planet Mars in astral theology
• Tyr, the Norse god of war
• Venus

References[link]

Mars  

Global view of Mars as seen by the Viking 1 orbiter in 1980, showing the Valles Marineris (center)
Designations
Pronunciation	i/ˈmɑrz/
Adjective	Martian
Orbital characteristics [1]
Epoch J2000
Aphelion	249,209,300 km 1.665 861 AU
Perihelion	206,669,000 km 1.381 497 AU
Semi-major axis	227,939,100 km 1.523 679 AU
Eccentricity	0.093 315
Orbital period	686.971 days 1.8808 Julian years 668.5991 sols
Synodic period	779.96 days 2.135 Julian years
Average orbital speed	24.077 km/s
Mean anomaly	19.3564°
Inclination	1.850° to ecliptic 5.65° to Sun's equator 1.67° to invariable plane[2]
Longitude of ascending node	49.562°
Argument of perihelion	286.537°
Satellites	2
Physical characteristics
Equatorial radius	3,396.2 ± 0.1 km[a] [3] 0.533 Earths
Polar radius	3,376.2 ± 0.1 km[a] [3] 0.531 Earths
Flattening	0.005 89 ± 0.000 15
Surface area	144,798,500 km2 0.284 Earths
Volume	1.6318×1011 km3[4] 0.151 Earths
Mass	6.4185×1023 kg[4] 0.107 Earths
Mean density	3.9335 ± 0.0004[4] g/cm³
Equatorial surface gravity	3.711 m/s²[4] 0.376 g
Escape velocity	5.027 km/s
Sidereal rotation period	1.025 957 day 24.622 9 h[4]
Equatorial rotation velocity	868.22 km/h (241.17 m/s)
Axial tilt	25.19°
North pole right ascension	21 h 10 min 44 s 317.681 43°
North pole declination	52.886 50°
Albedo	0.170 (geometric)[5] 0.25 (Bond)[6]
Surface temp.    Kelvin    Celsius	min mean max 186 K 210 K[6] 293 K[8] −87 °C −63 °C 20 °C
Apparent magnitude	+1.6 to −3.0[7]
Angular diameter	3.5–25.1"[6]
Atmosphere[6][9]
Surface pressure	0.636 (0.4–0.87) kPa
Composition	(mole fractions) 95.32% carbon dioxide 2.7% nitrogen 1.6% argon 0.13% oxygen 0.08% carbon monoxide 210 ppm water vapor 100 ppm nitric oxide 15 ppm molecular hydrogen[10] 2.5 ppm neon 850 ppb HDO 300 ppb krypton 130 ppb formaldehyde 80 ppb xenon 18 ppb hydrogen peroxide[11] 10 ppb methane[12]

Animation that rolls Mars around to show all the major features of the Martian topography.

Mars is the fourth planet from the Sun in the Solar System. Named after the Roman god of war, Mars, it is often described as the "Red Planet" as the iron oxide prevalent on its surface gives it a reddish appearance.^[13] Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts, and polar ice caps of Earth. The rotational period and seasonal cycles of Mars are likewise similar to those of Earth, as is the tilt that produces the seasons. Mars is the site of Olympus Mons, the highest known mountain within the Solar System, and of Valles Marineris, the largest canyon. The smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature.^[14][15]

Until the first successful flyby of Mars occurred in 1965, by Mariner 4, many speculated about the presence of liquid water on the planet's surface. This was based on observed periodic variations in light and dark patches, particularly in the polar latitudes, which appeared to be seas and continents; long, dark striations were interpreted by some as irrigation channels for liquid water. These straight line features were later explained as optical illusions, though geological evidence gathered by unmanned missions suggest that Mars once had large-scale water coverage on its surface.^[16] In 2005, radar data revealed the presence of large quantities of water ice at the poles,^[17] and at mid-latitudes.^[18][19] The Mars rover Spirit sampled chemical compounds containing water molecules in March 2007. The Phoenix lander directly sampled water ice in shallow Martian soil on July 31, 2008.^[20]

Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Martian trojan asteroid. Mars is currently host to three functional orbiting spacecraft: Mars Odyssey, Mars Express, and the Mars Reconnaissance Orbiter, and one on the surface, the Mars Exploration Rover Opportunity. Defunct spacecraft on the surface include MER-A Spirit, and several other inert landers and rovers, both successful and unsuccessful such as the Phoenix lander, which completed its mission in 2008. Observations by NASA's now-defunct Mars Global Surveyor show evidence that parts of the southern polar ice cap have been receding.^[21] Observations by the Mars Reconnaissance Orbiter have revealed possible flowing water during the warmest months on Mars.^[22]

Mars can easily be seen from Earth with the naked eye. Its apparent magnitude reaches −3.0^[7] a brightness surpassed only by Jupiter, Venus, the Moon, and the Sun. Optical ground based telescopes are typically limited to resolving features about 300 km (186 miles) across when Earth and Mars are closest, because of Earth's atmosphere.^[23]

Physical characteristics[link]

Size comparison of Earth and Mars.

Mars has approximately half the diameter of Earth. It is less dense than Earth, having about 15% of Earth's volume and 11% of the mass. Its surface area is only slightly less than the total area of Earth's dry land.^[6] While Mars is larger and more massive than Mercury, Mercury has a higher density. This results in the two planets having a nearly identical gravitational pull at the surface—that of Mars is stronger by less than 1%. The red-orange appearance of the Martian surface is caused by iron(III) oxide, more commonly known as hematite, or rust.^[24]

Geology[link]

Mars is a terrestrial planet that consists of minerals containing silicon and oxygen, metals, and other elements that typically make up rock. The surface of Mars is primarily composed of tholeiitic basalt,^[25] although parts are more silica-rich than typical basalt and may be similar to andesitic rocks on Earth or silica glass. Regions of low albedo show concentrations of plagioclase feldspar, with northern low albedo regions displaying higher than normal concentrations of sheet silicates and high-silicon glass. Parts of the southern highlands include detectable amounts of high-calcium pyroxenes. Localized concentrations of hematite and olivine have also been found.^[26] Much of the surface is deeply covered by finely grained iron(III) oxide dust.^[27][28]

Like Earth, this planet has undergone differentiation, resulting in a dense, metallic core region overlaid by less dense materials.^[29] Current models of the planet's interior imply a core region about 1794 ± 65 km in radius, consisting primarily of iron and nickel with about 16–17% sulfur.^[30] This iron sulfide core is partially fluid, and has twice the concentration of the lighter elements than exist at Earth's core. The core is surrounded by a silicate mantle that formed many of the tectonic and volcanic features on the planet, but now appears to be dormant. Besides silicon and oxygen, the most abundant elements in the martian crust are iron, magnesium, aluminum, calcium, and potassium. The average thickness of the planet's crust is about 50 km, with a maximum thickness of 125 km.^[31] Earth's crust, averaging 40 km, is only one third as thick as Mars’ crust, relative to the sizes of the two planets.

Although Mars has no evidence of a current structured global magnetic field,^[32] observations show that parts of the planet's crust have been magnetized, and that alternating polarity reversals of its dipole field have occurred in the past. This paleomagnetism of magnetically susceptible minerals has properties that are very similar to the alternating bands found on the ocean floors of Earth. One theory, published in 1999 and re-examined in October 2005 (with the help of the Mars Global Surveyor), is that these bands demonstrate plate tectonics on Mars four billion years ago, before the planetary dynamo ceased to function and the planet's magnetic field faded away.^[33]

During the Solar System's formation, Mars was created as the result of a stochastic process of run-away accretion out of the protoplanetary disk that orbited the Sun. Mars has many distinctive chemical features caused by its position in the Solar System. Elements with comparatively low boiling points such as chlorine, phosphorus and sulphur are much more common on Mars than Earth; these elements were probably removed from areas closer to the Sun by the young star's energetic solar wind.^[34]

After the formation of the planets, all were subjected to the so-called "Late Heavy Bombardment". About 60% of the surface of Mars shows a record of impacts from that era,^[35][36][37] while much of the remaining surface is probably underlain by immense impact basins caused by those events. There is evidence of an enormous impact basin in the northern hemisphere of Mars, spanning 10,600 km by 8,500 km, or roughly four times larger than the Moon's South Pole – Aitken basin, the largest impact basin yet discovered.^[14][15] This theory suggests that Mars was struck by a Pluto-sized body about four billion years ago. The event, thought to be the cause of the Martian hemispheric dichotomy, created the smooth Borealis basin that covers 40% of the planet.^[38][39]

The geological history of Mars can be split into many periods, but the following are the three primary periods:^[40][41]

• Noachian period (named after Noachis Terra): Formation of the oldest extant surfaces of Mars, 4.5 billion years ago to 3.5 billion years ago. Noachian age surfaces are scarred by many large impact craters. The Tharsis bulge, a volcanic upland, is thought to have formed during this period, with extensive flooding by liquid water late in the period.
• Hesperian period (named after Hesperia Planum): 3.5 billion years ago to 2.9–3.3 billion years ago. The Hesperian period is marked by the formation of extensive lava plains.
• Amazonian period (named after Amazonis Planitia): 2.9–3.3 billion years ago to present. Amazonian regions have few meteorite impact craters, but are otherwise quite varied. Olympus Mons formed during this period, along with lava flows elsewhere on Mars.

Some geological activity is still taking place on Mars. The Athabasca Valles is home to sheet-like lava flows up to about 200 Mya. Water flows in the grabens called the Cerberus Fossae occurred less than 20 Mya, indicating equally recent volcanic intrusions.^[42] On February 19, 2008, images from the Mars Reconnaissance Orbiter showed evidence of an avalanche from a 700 m high cliff.^[43]

Soil[link]

Rover exposes silica-rich dust