🔭 Astronomy Tools Suite

Julian Date Calculator

Converts a calendar date/time to Julian Date, which is used in astronomical timekeeping. JD = days since noon, January 1, 4713 BCE.

RA/Dec Converter

Convert RA from HH:MM:SS to degrees and Dec from DD:MM:SS to degrees. This format is standard in celestial coordinate systems.

Cosmology: Distance vs Redshift

Estimate comoving distance from redshift using a basic ΛCDM cosmology (H₀ = 70, Ωₘ = 0.3). Useful for large-scale structure studies.

Galactic Extinction Calculator

Computes extinction A(λ) using E(B-V) and band-specific R-values from Schlafly & Finkbeiner (2011). Useful for correcting observed magnitudes.

Angular Size Calculator

Convert physical size (in kpc) to angular size using angular diameter distance. θ = (D / DA) × 206.265 arcsec.

Lookback Time Calculator

Estimate the time since light left a galaxy, given redshift. Approximate formula: t = z / (1+z) × 13.8 Gyr.

Airmass Calculator (Simplified)

Estimate airmass using: airmass ≈ sec(z) = 1 / cos(90° – Altitude). Used to determine atmospheric attenuation.