sky.objects: Creates a _skyscapeR.object_ for plotting of celestial...
In skyscapeR: Data Analysis and Visualization for Skyscape Archaeology

This function creates an object containing all the necessary information to plot celestial objects/events unto the many plotting functions of skyscapeR package.

1	sky.objects(names, epoch, loc = FALSE, col = "red", lty = 1, lwd = 1)

`names`	The name(s) of the celestial object(s) or event(s) of interest. These can be one of the following soli-lunar events: jS, dS, eq, nmnLX, nMjLX, smnLX, sMjLX, or the name of any star in the database. As shorthand, the names sun and moon can be used to represent all the above solar and lunar events, respectively. Alternatively, custom declination values can also be used.
`epoch`	The year or year range (as an array) one is interested in.
`loc`	(Optional) This can be either a vector with the latitude and longitude of the location, or a skyscapeR.horizon object.
`col`	(Optional) The color for plotting, and differentiating these objects. Defaults to red for all objects.
`lty`	(Optional) Line type (see `par`) used for differentiation. Only activated for single year epochs.
`lwd`	(Optional) Line width (see `par`) used for differentiation. Only activated for single year epochs.

# Create a object with solar targets for epoch range 4000-2000 BC:
tt <- sky.objects('solar extremes', c(-4000,-2000))

# Create an object with a few stars for same epoch:
tt <- sky.objects(c('Sirius', 'Betelgeuse', 'Antares'), c(-4000,-2000),
col=c('white', 'red', 'orange'))

# Create an object with solstices and a custom declination value:
tt <- sky.objects(c('December Solstice','June Solstice', -13), c(-4000,-2000))