Search for peak magnitude of Venus — astro_search_peak

Searches for the next date and time when Venus will appear brightest as seen from Earth. This function currently only supports Venus.

Usage

astro_search_peak_magnitude(body, start_time)

Arguments

body: An integer representing the celestial body. Currently only astro_body["VENUS"] is supported. Returns error for other bodies.
start_time: A POSIXct datetime object specifying when to begin the search.

Value

A list containing:

time: The time of peak magnitude as a POSIXct object.
mag: Visual magnitude at peak brightness (numeric).
phase_angle: Phase angle in degrees (numeric).
phase_fraction: Fraction of Venus illuminated (numeric).
helio_dist: Distance from Sun in AU (numeric).
ring_tilt: Always 0 for Venus (numeric).

Details

Venus reaches peak magnitude (maximum brightness) at certain times in its orbit. This is distinct from other brightness events: Mercury's peak magnitude occurs at superior conjunction when it's invisible, and outer planets reach peak magnitude at opposition.

The search may require iterating through multiple synodic periods of Venus to find an event after the specified start time. The function will search forward from the start time until it finds a valid peak magnitude event.

Examples

# Find when Venus will next reach peak magnitude after 2025-01-01
start <- as.POSIXct("2025-01-01", tz = "UTC")
astro_search_peak_magnitude(astro_body["VENUS"], start)
#> $time
#> [1] "2025-02-17 10:02:11 UTC"
#> 
#> $mag
#> [1] -4.850427
#> 
#> $phase_angle
#> [1] 119.7786
#> 
#> $phase_fraction
#> [1] 0.2516749
#> 
#> $helio_dist
#> [1] 0.7184612
#> 
#> $ring_tilt
#> [1] 0
#>