* Astronomy

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RE: Astronomical nomenclature

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Closest exoplanet sparks international naming fight

A new war of the worlds has begun: The International Astronomical Union (IAU) has sparked planetary conflict after criticising a privately run effort to name exoplanets.
The private space outreach company Uwingu is running a contest encouraging the public to submit names for exoplanets and vote on their favourites, starting with the closest exoplanet to Earth, currently called Alpha Centauri Bb. Suggesting a name costs $4.99, and voting will set you back 99 cents. Uwingu says that up to half the proceeds will be used to fund space research and education projects.
But last week the IAU issued a press release warning the public that such schemes have no official bearing, and claiming it acts as the arbiter of the naming process in astronomy with advice and support from its members.
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Mercury Nomenclature

Catenae	Radio telescope facilities
Craters	Deceased artists, musicians, painters, and authors who have made outstanding or fundamental contributions to their field and have been recognised as art historically significant figures for more than 50 years
Dorsa	Deceased scientists who have contributed to the study of Mercury
Fossae	Significant works of architecture
Montes	Word for "hot" in various languages
Planitiae	Names for Mercury (either the planet or the god) in various languages
Rupes	Ships of discovery or scientific expeditions
Valles	Abandoned cities (or towns or settlements) of antiquity

Blobrana · L

Feature	Description	Designation
Albedo feature	An area which shows a contrast in brightness or darkness (albedo) with adjacent areas. This term is implicit.	AL
Arcus, arcs	Arc: curved feature	AR
Astrum, astra	Radial-patterned features on Venus	AS
Catena, catenae	A chain of craters e.g. Enki Catena.	CA
Cavus, cavi	Hollows, irregular steep-sided depressions usually in arrays or clusters	CB
Chaos	A distinctive area of broken or jumbled terrain e.g. Iani Chaos.	CH
Chasma, chasmata	Deep, elongated, steep-sided depression e.g. Eos Chasma.	CM
Colles	A collection of small hills or knobs.	CO
Corona, coronae	An oval feature. Used only on Venus and Miranda.	CR
Crater, craters	A circular depression likely created by impact event. This term is implicit.	AA
Dorsum, dorsa	Ridge, sometimes called a wrinkle ridge e.g. Dorsum Buckland.	DO
Eruptive center	An active volcano on Io. This term is implicit.	ER
Facula, faculae	Bright spot	FA
Farrum, farra	Pancake-like structure, or a row of such structures	FR
Flexus, flexs	Very low curvilinear ridge with a scalloped pattern	FE
Fluctus, flucts	Terrain covered by outflow from a volcano.	FL
Flumen, flumina	Channel on Titan that might carry liquid	FM
Fossa, fossae	Long, narrow, shallow depression	FO
Insula, insulae	Island (islands), an isolated land area (or group of such areas) surrounded by, or nearly surrounded by, a liquid area (sea or lake). The only feature with this designation is Mayda Insula.	IN
Labes, labes	Landslide debris. Used only on Mars.	LA
Labyrinthus, labyrinthi	Complex of intersecting valleys or ridges.	LB
Lacus	A "lake" or small plain. Used on the Moon, Mars and Titan.	LC
Landing site name	Lunar features at or near Apollo landing sites	LF
Large ringed feature	Cryptic ringed features	LG
Lenticula, lenticulae	Small dark spots on Europa	LE
Linea, lineae	Dark or bright elongate marking, may be curved or straight	LI
Macula, maculae	Dark spot, may be irregular	MA
Mare, maria	A "sea" or large circular plain e.g. Mare Erythraeum. Used on the Moon, Mars and Titan.	ME
Mensa, mensae	A flat-topped prominence with cliff-like edges, i.e. a mesa.	MN
Mons, montes	Mons refers to a mountain. Montes refers to a mountain range.	MO
Oceanus	Very large dark area. Used only on the Moon.	OC
Palus, paludes	"Swamp"; small plain. Used on the Moon and Mars.	PA
Patera, paterae	Irregular crater, or a complex one with scalloped edges e.g. Ah Peku Patera. Usually refers to the dish-shaped depression atop a volcano.	PE
Planitia, planitiae	Low plain e.g. Amazonis Planitia.	PL
Planum, plana	A plateau or high plain e.g. Planum Boreum.	PM
Plume	A cryovolcanic feature on Triton. This term is currently unused.	PU
Promontorium, promontoria	"Cape"; headland. Used only on the Moon.	PR
Regio, regiones	Large area marked by reflectivity or color distinctions from adjacent areas, or a broad geographic region	RE
Reticulum, reticula	reticular (netlike) pattern on Venus	RT
Rima, rimae	Fissure. Used only on the Moon.	RI
Rupes, rupees	Scarp	RU
Satellite feature	A feature that shares the name of an associated feature, for example Hertzsprung D.	SF
Scopulus, scopuli	Lobate or irregular scarp	SC
Sinus	"Bay"; small plain e.g. Sinus Meridiani.	SI
Sulcus, sulci	Subparallel furrows and ridges	SU
Terra, terrae	Extensive land mass e.g. Arabia Terra.	TA
Tessera, tesserae	An area of tile-like, polygonal terrain. This term is used only on Venus.	TE
Tholus, tholi	Small domical mountain or hill e.g. Hecates Tholus.	TH
Undae	A field of dunes.	UN
Vallis, valles	A valley e.g. Valles Marineris.	VA
Vastitas, vastitates	An extensive plain. The only feature with this designation is Vastitas Borealis.	VS
Virga, virgae	A streak or stripe of color	VI

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Provisional designation

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RE: Astronomical nomenclature

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Title: "Galaxy," Defined
Authors: Beth Willman, Jay Strader

A growing number of low luminosity and low surface brightness astronomical objects challenge traditional notions of both galaxies and star clusters. To address this challenge, we propose a definition of galaxy that does not depend on a cold dark matter model of the universe: A galaxy is a gravitationally bound collection of stars whose properties cannot be explained by a combination of baryons and Newton's laws of gravity. We use this definition to critically examine the classification of ultra-faint dwarfs, globular clusters, ultra-compact dwarfs, and tidal dwarfs. While kinematic studies provide an effective diagnostic of the definition in many regimes, they can be less useful for compact or very faint systems. To explore the utility of using the [Fe/H] spread as a diagnostic, we use published spectroscopic [Fe/H] measurements of 16 Milky Way dwarfs and 24 globular clusters to uniformly calculate their [Fe/H] spreads and associated uncertainties. Our principal results are: (i) no known, old star cluster with M_V > -10 has a significant (~> 0.1 dex) spread in its iron abundance; (ii) most known ultra-faint dwarfs can be unambiguously classified with a combination of kinematic and [Fe/H] observations; (iii) the observed [Fe/H] spreads in massive (~> 10^6 solar masses) globular clusters do not necessarily imply that they are the stripped nuclei of dwarfs, nor a need for dark matter; and (iv) if ultra-compact dwarf galaxies reside in dark matter halos akin to those of ultra-faint dwarfs of the same half-light radii, then they will show no clear dynamical signature of dark matter. We suggest several measurements that may assist the future classification of massive globular clusters, ultra-compact dwarfs, and ultra-faint galaxies.

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Scientific terminology

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Astronomical nomenclature

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Asteroid 155083 Banneker (2005 SE134)

Now, the name of Calvin's newest named asteroid departs from the college's history or even any college connections. Instead Asteroid Banneker, discovered in 2005 by Calvin professor of physics Larry Molnar and approved for naming last winter, draws its moniker from a man who lived from 1731 to 1806, but had a late start in life as an amateur astronomer, taking up the pursuit at the age of 57 after being inspired by the "pavement astronomy" of a neighbour.
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