De systemate orbis cometici, deque admirandis coeli characteribus

From Infogalactic: the planetary knowledge core
Jump to: navigation, search

De systemate orbis cometici, deque admirandis coeli characteribus (transl. Of the systematics of the world of comets, and on the admirable objects of the sky) is a small tract on comets and other sky objects by the Sicilian astronomer Giovanni Battista Hodierna published in 1654.[1] It contains a catalogue of comets and other sky objects, but had limited circulation and the work was forgotten until 1985.[1][2] In this work, Hodierna expressed the belief that comets were made of a more terrestrial substance, and considered nebulae to be made up of stars (Lux Primogenita).[1][2]

Scope

The first part of his work (De systemate orbis cometici) followed Galileo's ideas on comets.[1][2] The second part (De admirandis coeli characteribus) consisted of four main sections. The first concerns the classification of nebulaes. Hodierna classified the objects into three types according to their resolvability. Luminosae, or star clusters to the naked eye, Nebulae, or clusters that appeared nebulous to the naked eye, but which were resolvable in his telescope, and Occultae, which did not resolve even with the aid of his telescope.[1][2] The second part is a list of 40 nebulae, of which roughly 25 have been identified as known objects, the others having too unclear a description for a modern identification.[1] The third section is an attempt at a unifying theory of celestial objects, and the fourth concerns Copernican heliocentrism.[2]

Discoveries

Hodernia is credited with several first descriptions, discoveries and rediscoveries:[1][3]

Column-generating template families

The templates listed here are not interchangeable. For example, using {{col-float}} with {{col-end}} instead of {{col-float-end}} would leave a HTML "div" (division) open, potentially harming any subsequent formatting.

Column templates
Type Family
Handles wiki
 table code?dagger
Responsive/
Mobile suited
Start template Column divider End template
Float "Col-float" Yes Yes {{Col-float}} {{Col-float-break}} {{Col-float-end}}
"Columns-start" Yes Yes {{Columns-start}} {{Column}} {{Columns-end}}
Columns "Div col" Yes Yes {{Div col}} {{Div col end}}
"Columns-list" No Yes {{Columns-list}} (wraps div col)
Flexbox "Flex columns" No Yes {{Flex columns}}
Table "Col" Yes No {{Col-begin}},
{{Col-begin-fixed}} or
{{Col-begin-small}}
{{Col-break}} or
{{Col-2}} .. {{Col-5}}
{{Col-end}}

dagger Can template handle the basic wiki markup {| | || |- |} used to create tables? If not, special templates that produce these elements (such as {{(!}}, {{!}}, {{!!}}, {{!-}}, {{!)}})—or HTML tags (<table>...</table>, <tr>...</tr>, etc.)—need to be used instead. These discoveries were part of an attempt at compiling a sky atlas, Il Cielo Stellato Diviso in 100 Mappe, but the work was never completed.[1]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Lua error in package.lua at line 80: module 'strict' not found.
  2. 2.0 2.1 2.2 2.3 2.4 Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.

Further reading

  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found.
  • Lua error in package.lua at line 80: module 'strict' not found.