What is "collis"

Collis may refer to:

• Collis (surname)
• Collis (planetary geology), a term used in planetary geology for a small hill or knob
• Collis, Minnesota, an unincorporated community
• Collis, former name of Kerman, California
• Collis Potter Huntington (1821-1900), American railway executive

Collis (plural: colles, from the Latin word for "hill") is a small hill or knob on a celestial body. The term is used in planetary nomenclature: it is a part of international proper names of such features. Like other generic terms, it is capitalized and stands after the proper name (for example, Bilbo Colles; the only exception is Colles Nili on Mars). As of 2015, only groups of the hills have names, and the term is used only in plural.

Like the other terms of planetary nomenclature, this word describes only external view of the features, but not their origin or geological structure. So, it is used for hills of any origin. Names of bigger (especially domical) uplands usually contain the term Tholus ("dome"), and the names of still bigger mountains – the term Mons ("mountain"). Peculiar round mountains, which are found on Venus, get names with the term Farrum.

The term Collis was introduced into planetary nomenclature in 1982, on XVIIIth General Assembly of International Astronomical Union. This year two groups of hills on Mars were named ( Ariadnes Colles and Deuteronilus Colles). As of May 2015, 43 such groups are named: 22 on Mars, 16 on Venus and 5 on Titan. On different celestial bodies they are named differently:

• on Venus, after sea goddesses
• on Mars, after nearby albedo features on classical maps by Giovanni Schiaparelli or Eugène Antoniadi
• on Titan, after characters from Tolkien's Middle-earth
• on Pluto, after pioneering spacecraft

Olosa Colles (Magellan) part.png|Part of Olosa Colles on Venus Acidalia Colles (THEMIS) part.png|Part of Acidalia Colles on Mars Nimloth Colles (Cassini, T43).png| Nimloth Colles on Titan

Collis is a surname. Notable people with the surname include:

• Charles Collis (1838–1902), Irish-American US Army officer in the American Civil War
• Dean Collis (born 1985), Australian rugby player
• Gordon Collis (born 1940), Australian rules footballer
• Jack T. Collis (1923–1998), American art director
• James Collis (1856–1918), English soldier
• John Collis (born 1944), British prehistorian
• John Day Collis (1816–1879), British headmaster and educational writer
• John Stewart Collis (1900–1984), British author
• Luke Collis (born 1988), American football player
• Maurice Collis (1889–1973), British colonial administrator and writer
• Robert Collis (1900–1975), Irish doctor and writer
• Shannon Collis (born 1986), American actress
• Simon Collis (born 1956), British ambassador
• Steve Collis (born 1891), English football goalkeeper
• Susan Collis (born 1956), British artist